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Journal of Chemical Education中关于化学批判性思维的文献分析 认领
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作者 何为 李茂柯 +1 位作者 黄倩 伍晓春 《化学教育(中英文)》 CAS 北大核心 2021年第4期96-101,共6页
通过对1987年到2019年在Journal of Chemical Education上出版的所有以"Critical Thinking"为主题的文献进行内容分析,将这些文献分为5个类别,并从每一个类别中选择最具有代表性的一篇文献作为实例,从实验的过程分析、主动学... 通过对1987年到2019年在Journal of Chemical Education上出版的所有以"Critical Thinking"为主题的文献进行内容分析,将这些文献分为5个类别,并从每一个类别中选择最具有代表性的一篇文献作为实例,从实验的过程分析、主动学习教学法、课程设置方案、纠正教科书错误、分析网络信息等5个维度提供了发展批判性思维能力的路径。最后总结了目前国际化学教育关于批判性思维的研究现状和趋势。 展开更多
关键词 国际化学教育 Journal of Chemical Education 化学批判性思维 文献分析
The Astrophysical Processes of Cosmological Hydrogen that Generate the Chemical Elements that Make up the Universe 认领
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作者 M. Javier Cruz Gómez Salvador Galindo Uribarri Olga B. Benítez López 《自然科学期刊(英文)》 2021年第3期103-116,共14页
The objective of the present article is to explain how all the chemical elements were formed from the big bang generated element: hydrogen. The methodology used was to analyze the main cosmological and astrophysical p... The objective of the present article is to explain how all the chemical elements were formed from the big bang generated element: hydrogen. The methodology used was to analyze the main cosmological and astrophysical processes in order to explain the origin of all the known chemical elements. The main results are: Hydrogen cannot be formed in any part of the actual universe;it must come from the Big Bang. Helium and a little bit of lithium can have a cosmological origin associated to the Big Bang nucleosynthesis and the recombination process. The elements with an atomic number between 3 and 26 were, and continue to be, synthetized by </span><span style="font-family:Verdana;font-size:12px;">nuclear fusion reactions inside the core of massive stars and liberated by explosion when the stars go supernovae, at the end of their lives. In the process of going supernova, elements with a medium atomic number, between 27 and 40, are created. All the elements with an atomic number larger than 40 were generated by neutron star collisions. When Mendeleev and Lothar Meyer designed an ordered arrangement of chemical elements, their tables included the 63 chemical elements known in 1869. A century and a half later, the known elements are 118. By studying different topics related to the elements, it was possible to uncover fundamental particles, such as quarks and leptons, and the strong and weak nuclear forces that form the baryonic part of the universe. The Sun was formed 6000 million years ago and its planets, including earth, were formed 4600 million years ago when and where there were debris of different stars that went supernova, in particular 1A type, and also debris, of at least one of a binary neutron star collision, so to attain, all the elements that have been identified in the solar system, and especially in earth. In addition, the current “periodic table” includes 26 synthetic elements that were produced in neutron star collisions but, because of their short lifetimes, they are not found, on earth. The vast quanti 展开更多
关键词 Origin of Chemical Elements Fundamental Particles Nuclear Reactions Inside the Stars Binary Stars Neutron Star Collision
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Low-α metal-rich stars with sausage kinematics in the LAMOST survey: Are they from the Gaia-Sausage-Enceladus galaxy? 认领
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作者 Gang Zhao Yuqin Chen 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2021年第3期14-26,共13页
We search for metal-rich Sausage-kinematic(MRSK)stars with[Fe/H]>−0.8 and−100<Vϕ<50 km/s in LAMOST DR5 in order to investigate the influence of the Gaia-Sausage-Enceladus(GSE)merger event on the Galactic disk... We search for metal-rich Sausage-kinematic(MRSK)stars with[Fe/H]>−0.8 and−100<Vϕ<50 km/s in LAMOST DR5 in order to investigate the influence of the Gaia-Sausage-Enceladus(GSE)merger event on the Galactic disk.For the first time,we find a group of low-αMRSK stars,and classify it as a metal-rich tail of the GSE galaxy based on the chemical and kinematical properties.This group has slightly larger Rapo,Zmax and Etot distributions than a previously-reported high-αgroup.Its low-αratio does not allow for an origin resulting from the splash process of the GSE merger event,as is proposed to explain the high-αgroup.A hydrodynamical simulation by Amarante et al.provides a promising solution,in which the GSE galaxy is a clumpy Milky-Way analogue that develops a bimodal disk chemistry.This scenario explains the existence of MRSK stars with both high-αand low-αratios found in this work.It is further supported by another new feature that a clump of MRSK stars is located at Zmax=3-5 kpc,which corresponds to the widely adopted disk-halo transition at|Z|∼4 kpc.We suggest that a pile-up of MRSK stars at Zmax contributes significantly to this disk-halo transition,an interesting imprint left by the GSE merger event.These results also provide an important implication on the connection between the GSE and the Virgo Radial Merger. 展开更多
关键词 Galactic halo spiral arms and Galactic disk chemical composition and chemical evolution kinematics and dynamics rotation
Bulk Etch Rate of LR 115 Polymeric Radon Detector 认领
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作者 Dabo S. I. Agba Koudou Djagouri +1 位作者 Bogbe D. L. H. Gogon Aka A. Koua 《检测(英文)》 2021年第1期1-8,共8页
In this study, we used strippable LR 115 type 2 which is a Solid State Nuclear Track Detector (SSNTD) widely known for radon gas detection and measurement. The removed thickness of the active layer of samples of this ... In this study, we used strippable LR 115 type 2 which is a Solid State Nuclear Track Detector (SSNTD) widely known for radon gas detection and measurement. The removed thickness of the active layer of samples of this SSNTD, were determined by measuring the average initial thickness (before etching) and residual thickness after 80 to 135 minutes chemical etching in the standard conditions, using an electronic comparator. These results allowed the calculation of the bulk etch rate of this detector in a simple way. The mean value obtained is (3.21 ± 0.21) μm/h. This value is in close agreement with those reported by different authors. It is an important parameter for alpha track counting on the sensitive surface of this polymeric detector after chemical etching because track density depends extremely on its removed layer. This SSNTD was then used for environmental radon gas monitoring in C&#244;te d’Ivoire. 展开更多
关键词 Strippable LR 115 Type 2 Chemical Etching Removed Layer Bulk Etch Rate
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Iron in Water: Study of Iron Removal Kinetics in Chemically Reconstituted Waters: Application to Groundwater of South Pout (PS2 Site) 认领
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作者 Faye Mamadou Sambe Falilou Mbacké +3 位作者 Diop El Hadji Moussa Toure Alpha Ousmane Mbaye Fall Aminata Diop Mar Codou Guèye 《金属学报(美国)》 2021年第1期1-10,共10页
The goal of this topic is a synthesis of the main characteristics of iron in groundwater and the oxidation process used to remove it. Indeed, the kinetics of chemical oxidation of iron (II) was examined with reconstit... The goal of this topic is a synthesis of the main characteristics of iron in groundwater and the oxidation process used to remove it. Indeed, the kinetics of chemical oxidation of iron (II) was examined with reconstituted water (distilled water + iron sulphate) and proceeded to the application in the groundwater samples taken from <em><strong>South Pout</strong></em> (Senegal) precisely in the drilling <strong>PS2</strong>. The sources of iron are natural or anthropogenic. In Senegalese waters, its content is variable and sometimes exceeds the standards of potability. Despite the diversification of iron removal process, chemical oxidation is the most used solution in drinking water treatment plants in Senegalese rural areas. Applied oxidation processes such as aeration and chlorination, however, are insufficient to produce drinking water with an iron concentration in accordance with standards of potability. 展开更多
关键词 IRON KINETICS Chemical Oxidation GROUNDWATER Drilling
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Study of Species <i>Lycium</i>L. of Rangeland Ecosystems of Uzbekistan in the Arid Zone Conditions 认领
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作者 Nodira Nurullayeva Khislat Khaydarov +2 位作者 Zebiniso Umurzakova D. Imomova Tolib Mukumov 《美国植物学期刊(英文)》 2021年第3期476-485,共10页
The article presents the features of biology and ecology, growth and development of various </span><i><span style="font-family:Verdana;">Lycium</span></i><span style="fo... The article presents the features of biology and ecology, growth and development of various </span><i><span style="font-family:Verdana;">Lycium</span></i><span style="font-family:Verdana;"> L</span></span><span style="font-family:Verdana;">.</span><span style="font-family:""><span style="font-family:Verdana;"> species in different ecological conditions of Uzbekistan. The distribution area covers mainly semi-desert and desert zones of Uzbekistan and the description of co-growing coenoses is presented. Based on the study of ecological and biological properties and economically valuable characteristics of </span><i><span style="font-family:Verdana;">Lycium</span></i><span style="font-family:Verdana;"> L</span></span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> species, ecologically significant species were selected as a source material for introduction into culture and use in pharmacology. Useful properties and harms are presented. 展开更多
关键词 Fodder Plants Drought Tolerance Semi-Deserts Deserts Plant Communities Yield Eat Ability Chemical Compositions
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Effect of Durian Peel Ash Added in Zinc Oxide/Reduced Graphene Oxide Composites Used as a Chemical Sensor for Hydrazine Detection 认领
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作者 Santi Rattanaveeranon Knavoot Jiamwattanapong Nattaphorn Jandee 《材料科学与应用期刊(英文)》 2021年第2期111-120,共10页
As the hydrazine is toxic, the methods to detect hydrazine at low concentrations are essential in scientific research. This preliminary study reported on how to increase the efficiency of ZnO/reduced graphene oxide (r... As the hydrazine is toxic, the methods to detect hydrazine at low concentrations are essential in scientific research. This preliminary study reported on how to increase the efficiency of ZnO/reduced graphene oxide (rGO) by adding durian peel ash (DPA) and using three-electrode method. The ZnO/rGO composites were prepared using chemical reaction of graphene oxide (GO) with zinc chloride. The rGO was prepared by the chemical reduction of GO using hydrazine. The properties of the samples were investigated using scanning electron microscopy, atomic force microscopy, X-ray diffraction, and Potentiostat/Galvanostat. The results showed that the optimal condition for the composite material was 70%DPA:30%ZnO/rGO with the sensitivity of 222.92 mA/mM<span style="white-space:nowrap;">·</span>cm<sup>2</sup> and the current density up to 116.50 ± 0.95 A/g. The relationship between the current and the hydrazine concentration was I (μA) = 48.69 + 21.91C (mM) with R<sup>2</sup> of 0.9870. The minimum concentration of hydrazine solution that the modified electrode can measure was 0.125 mM. The DPA powder can then be used to enhance the hydrazine detection efficiency at low concentrations. 展开更多
关键词 Durian Peel Ash Zinc Oxide Reduced Graphene Oxide Chemical Sensor
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Manufacturing of Composite Pasta by a Mixing Plan 认领
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作者 Laurette Brigelia Nkeletela Fanny Belgonde Ganongo-Po +5 位作者 André Kimbonguila Salomé Itoua Guenonie Louis Matos Jeremy Petit Joel Scher Jean Mathurin Nzikou 《食品与营养科学(英文)》 2021年第2期206-221,共16页
The partial replacement of durum wheat semolina with local flours such as soybeans and yam reduces the dependence of durum wheat semolina for the production of pasta</span><span style="font-family:Verdan... The partial replacement of durum wheat semolina with local flours such as soybeans and yam reduces the dependence of durum wheat semolina for the production of pasta</span><span style="font-family:Verdana;">.</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">The</span><span style="font-family:""><span style="font-family:Verdana;"> main objective of this study is to develop yam flour (A) from Dioscorea alata in the manufacture of pasta made with durum wheat semolina (B) and soy flour (C) (raw materials). The methodology adopted consists first of all in the characterization of yam, soybean </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> durum wheat semolina. An experimental design was developed to bring out the balanced mixing plan in well-defined proportions with ten (10) tests. Chemical and functional analyzes were carried out on the pastes obtained from these formulations. The functional properties allowed us to determine the optimal mixing plan using a mathematical model. The sensory properties of the optimal compound dough were estimated in comparison with the control doughs. The results on the chemical properties of raw materials A, B </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> C obtained on the water content vary from 10.29% to 12.29%;those of ashes vary from 0.91% to 5.74% and those of proteins vary from 3.24% to 20.17%. The results of the chemical and functional parameters of compound pasta gave very diverse values. We find that the water content, the ash content, the protein content </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> the acidity rate of the series of 10 tests are respectively from 6.60% to 14.97%, from 0.97% to 1.67%, from 7.15% to 12.10% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> from 1.35% to 3.60%. Regarding the optimal cooking time for this series of 10 tests, it varies from 15 min to 20 m 展开更多
关键词 Compound Pasta Chemical and Functional Parameters Optimization Sensory Test
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Investigation of Pegmatite Mineral Applicability from the Terek Ceramic Deposit in Kyrgyzstan for Production of Porcelain and Earthenware 认领
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作者 Mairam Abdullaeva Bektemir Murzubraimov +4 位作者 Dilbar Altybaeva Zhypargul Abdullaeva Gulzada Kalykova Aishakan Suiunbekova Aitgul Osmonova 《矿物质和材料特性和工程(英文)》 2021年第2期169-179,共11页
This article is investigating analysis and chemical composition of ceramic pegmatite minerals obtained from the Terek deposit in Toktogul district of Kyrgyzstan. Several methods such as mineralogical studies, magnetic... This article is investigating analysis and chemical composition of ceramic pegmatite minerals obtained from the Terek deposit in Toktogul district of Kyrgyzstan. Several methods such as mineralogical studies, magnetic and gravitational enrichments, silicate and chemical analyses of ceramic pegmatite minerals, quartz-feldspathic concentrate and sludge removal have been performed for determination of pegmatite mineral applicability for production of porcelain and earthenware. 展开更多
关键词 Ceramic Pegmatite Quartz-Feldspar Concentrate Sludge Magnetic Enrichment Gravitational Enrichment Iron Oxides Spectral and Chemical Analysis
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Physi-Chemical Property Research of Polysaccharides from Pomegranate Flowers 认领
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作者 Lixin Peng Yizhao Huang +2 位作者 Wei Tan Zhiwei Wei Lihua Zhang 《农业科学(英文)》 2021年第2期59-67,共9页
<div style="text-align:justify;"> Pomegranate flowers as row materials were used for extraction of polysaccharides by water-extraction and alcohol-precipitation method. After purification, the physical... <div style="text-align:justify;"> Pomegranate flowers as row materials were used for extraction of polysaccharides by water-extraction and alcohol-precipitation method. After purification, the physical and chemical properties, structure, monosaccharide composition and molecular weight were studied. The results showed that the polysaccharides from pomegranate flowers mainly contained two kinds of water soluble acidic polysaccharides, and monosaccharide composition were arabinose and galactose, both contained hydroxyl, carboxyl, amino, hydroxyl radical, sulfate, beta glycosidic bond and alpha glycosidic bond structure. The molecular weight of PP1 and PP2 were 6.16 × 104 (±6.6%) and 9.01 × 104 (±3.2%), respectively. The results of this study laid the foundation for further development and application of polysaccharides from pomegranate flowers. </div> 展开更多
关键词 POLYSACCHARIDES Pomegranate Flowers Physical and Chemical Properties
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Forward osmosis coupled with lime-soda ash softening for volume minimization of reverse osmosis concentrate and CaCO3 recovery: A case study on the coal chemical industry 认领
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作者 Jiandong Lu Shijie You Xiuheng Wang 《环境科学与工程前沿(英文)》 SCIE EI CSCD 2021年第1期135-144,共10页
Reverse osmosis(RO)is frequently used for water reclamation from treated wastewater or desalination plants.The RO concentrate(ROC)produced from the coal chemical industry(CCI)generally contains refractory organic poll... Reverse osmosis(RO)is frequently used for water reclamation from treated wastewater or desalination plants.The RO concentrate(ROC)produced from the coal chemical industry(CCI)generally contains refractory organic pollutants and extremely high-concentration inorganic salts with a dissolved solids content of more than 20 g/L contributed by inorganic ions,such as Na+,Ca2+,Mg2+,Cl,and SO42−.To address this issue,in this study,we focused on coupling forward osmosis(FO)with chemical softening(FO-CS)for the volume minimization of CCI ROC and the recovery of valuable resources in the form of CaCO3.In the case of the real raw CCI ROC,softening treatment by lime-soda ash was shown to effectively remove Ca2+/Ba2+(>98.5%)and Mg2+/Sr2+/Si(>80%),as well as significantly mitigate membrane scaling during FO.The softened ROC and raw ROC corresponded to a maximum water recovery of 86%and 54%,respectively.During cyclic FO tests(4×10 h),a 27%decline in the water flux was observed for raw ROC,whereas only 4%was observed for softened ROC.The cleaning efficiency using EDTA was also found to be considerably higher for softened ROC(88.5%)than that for raw ROC(49.0%).In addition,CaCO3(92.2%purity)was recovered from the softening sludge with an average yield of 5.6 kg/m3 treated ROC.This study provides a proof-of-concept demonstration of the FO-CS coupling process for ROC volume minimization and valuable resources recovery,which makes the treatment of CCI ROC more efficient and more economical. 展开更多
关键词 Coal chemical industry Forward osmosis Chemical softening Reverse osmosis concentrate
球磨辅助化学热洗处理含聚油泥的研究 认领
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作者 董丁 陈亮 +2 位作者 刘晓丽 卢彦珍 钟世坤 《石油与天然气化工》 CAS CSCD 北大核心 2021年第2期120-126,共7页
采用球磨辅助化学热洗处理含聚油泥中的矿物油,考察球磨配合4种无机盐7种表面活性剂作用于含聚油泥的除油效果,通过调整复配药剂含量、反应液温度、料液比和球磨时间,最终确定了含聚油泥除油配方和除油条件。实验结果表明,碱性无机盐和... 采用球磨辅助化学热洗处理含聚油泥中的矿物油,考察球磨配合4种无机盐7种表面活性剂作用于含聚油泥的除油效果,通过调整复配药剂含量、反应液温度、料液比和球磨时间,最终确定了含聚油泥除油配方和除油条件。实验结果表明,碱性无机盐和非离子表面活性剂复配处理含聚油泥除油效果显著,阴离子表面活性剂其次,阳离子表面活性剂几乎无效果。以100 g含聚油泥(含油质量分数42.8%)为例,球磨辅助复配药剂处理含聚油泥除油率最高达97.5%。其中,复配药剂组成为NaOH、JFC-G和H-66,其复配比例6∶4∶1,复配药剂质量分数0.40%,含聚油泥除油温度75℃,料液比1∶5,球磨时间30~40 min。 展开更多
关键词 球磨 化学药剂 含聚油泥 化学热洗
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DFT Study of Dimerization Sites in Imidazo[1,2-a]pyridinyl-chalcone Series 认领
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作者 Bibata Konate Sopi Thomas Affi Nahossé Ziao 《计算化学(英文)》 2021年第1期1-17,共17页
Quantum chemistry methods were performed in order to characterize the chemical reactivity on series of imidazo[1,2-a]pyridinyl-chalcone (IPC). In particular, the B3LYP/6-311G(d) theory level has been used to determine... Quantum chemistry methods were performed in order to characterize the chemical reactivity on series of imidazo[1,2-a]pyridinyl-chalcone (IPC). In particular, the B3LYP/6-311G(d) theory level has been used to determine parameters which characterize the global and local reactivity on five molecules of the series. These compounds differ from one to another with the aryl groups. There are: 1-(2-methylimidazo[1,2-a]pyridin-3-yl)-3-phenylprop-2-en-1-one, 3-(4-fluorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one, 3-[4-(dimethylamino)phenyl]-1-(2-methylimidazo [1,2-a]pyridin- 3-yl)prop-2-en-1-one, 3-(2,4-dichlorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one, 3-(2,4-dichlorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one. All results lead to finding out that local nucleophilicity and electrophilicity of compounds are not substituent-dependant contrarily to their global nucleophilicity which prove to be more sensitive to the electron-donating character of the substituents. 3-[4-(Dimethylamino) phenyl]-1-(2-methylimidazo[1,2-a]pyridin-3-yl)prop-2-en-1-one was identified as the unique nucleophile compound by global reactivity. Respectively, the carbon atoms C5 and C14 are the prediction sites of electrophilic and nucleophilic attacks in the molecular skeleton of both molecules. Identification of interactions centres on IPC series is of great importance for organic synthesis and medicinal chemistry where the molecular hybridization strategy is very often used to improve biological activities of interesting therapeutic systems. 展开更多
关键词 Chemical Reactivity Conceptual DFT Imidazopyridinyl-Chalcone Nematicidal Activity Quantum Chemistry
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Computational Stimulation and Experimental Study on Corrosion Inhibition Qualities of <i>Emilia sonchifolia</i>Leaf Extract for Copper (CU131729) in Hydrochloric Acid 认领
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作者 Raphael S. Oguike Omolara Oni +6 位作者 Aisha U. Barambu Davoud Balarak Toma Buba Chioma U. Okeke Lawrence S. Momoh Shakede Onimisi Williams J. Nwada 《计算化学(英文)》 2021年第1期18-36,共19页
Copper corrosion inhibition by Emilia sonchifolia (ES) leaf extract has been studied in 2 M hydrochloric acid solution using electrochemical measurement, energy dispersive X-ray emission spectroscopy and surface exami... Copper corrosion inhibition by Emilia sonchifolia (ES) leaf extract has been studied in 2 M hydrochloric acid solution using electrochemical measurement, energy dispersive X-ray emission spectroscopy and surface examination techniques. Computational simulations were adopted to describe probable reactiveness of individual ES leaf constituents and mechanism of interaction with copper crystal. Results obtained from potentiodynamic polarization revealed a shift in corrosion potentials of copper (CU131729) to more positive potentials in the presence of ES leaf extract with increased effect as inhibitor concentration increased and also a decrease in both current densities suggesting a mixed type inhibitor characteristics with pronounced anodic protection. Surface elemental characterization revealed presence of the inhibitor species in the corrosion products formed on corroded CU131729 surface confirming the formation of complex chelating ligands through interactions with the metal surface. Quantum chemical calculations and molecular dynamics simulations were employed to theoretically analyse the interactions of individual ES leaf constituent with copper surface at the molecular level and obtained results revealed strong and spontaneous adsorption with high binding energies which affirms observed quality inhibition action. Quantum chemical descriptors such as energy of HOMO and LUMO, energy gap, number of transferred electrons, global hardness and softness, electrophilicity, and interaction energy were computed and discussed. 展开更多
关键词 Copper Corrosion Emilia sonchifolia Surface Analysis Quantum Chemical Calculation Binding Energy PASSIVATION
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Development of Split-Protein Systems: From Binary to Ternary System 认领
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作者 Shengyi Shen 《生命科学与技术进展(英文)》 2021年第3期78-94,共17页
Tens of thousands of protein-protein interactions (PPIs) have been found in human cells and many of these macromolecular partnerships could determine the cell growth and death. Thus there is a need to develop the meth... Tens of thousands of protein-protein interactions (PPIs) have been found in human cells and many of these macromolecular partnerships could determine the cell growth and death. Thus there is a need to develop the methods to catalogue these macromolecules by detecting their interactions, modifications, and cellular locations. It will be helpful for scientists to compare the difference between a diseased cellular state and its normal state and to find the potential therapy treatment to intervene this status. One technology called split-protein reassembly or protein fragment complementation has been developed in the last two decades. This technology makes use of appropriate fragmentation of some protein reporters and the refolding of these reports could be detected by their function to confirm the interaction of interest. This system has been set up in cell-free systems, </span><i><span style="font-family:Verdana;">E.</span></i></span><i><span style="font-family:""> </span></i><i><span style="font-family:Verdana;">coli</span></i><span style="font-family:""><span style="font-family:Verdana;">, yeast, mammalian cells, plants and live animals. Herein, I present the development in fluorescence- and bioluminescence-based split-protein biosensors in both binary and ternary systems. In addition, some people developed the split-protein system by combining it with chemical inducer of dimerization strategy (CID). This has been applied for identifying the enzyme inhibitors and regulating the activity of protein kinases and phosphatases. With effort from many laboratories from the world, a variety of split-protein systems have been developed for studying the PPI </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">in vivo</span></i><span style="font-family:Verdana;">, monitoring the biological process, and controlling the activity of the enzyme of interest. 展开更多
关键词 Split-Protein Reassembly Protein Fragment Complementation Chemical In-ducer of Dimerization (CID) Protein-Protein Interaction (PPI)
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Physico-Chemical and Microbiological Study for the Stability of Phenytoin Sodium Extemporaneously Compounded Suspension in Saudi Arabia Hospitals 认领
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作者 Syed Ata ur Rahman Abdullah Alsaedi +6 位作者 Abdulelah Alhusayni Abdulmalik Alqurshi Sameh Ahmed Yaser M. Alahmadi Alaa Omer M. Abdullaal Badr Ahmed A. Taher El-Sayed E. Habib 《药理与制药(英文)》 2021年第1期1-9,共9页
<span style="font-family:Verdana;">Epilepsy is a chronic and the fourth most common neurological disorder which affects people of all age groups. Recently research and awareness on epilepsy-related dea... <span style="font-family:Verdana;">Epilepsy is a chronic and the fourth most common neurological disorder which affects people of all age groups. Recently research and awareness on epilepsy-related deaths have rapidly grown over the past two decades. Many previous studies are attributed to the guidelines that apprise health care professionals in handling these deaths, but there is a relative scarcity of information accessible for clinicians and pharmacists who are responsible for manufacturing or preparing the extemporaneous anti-epileptic suspensions in the hospitals. Mostly in partial seizures, phenytoin is one of the first-choice drugs. In Saudi Arabian hospitals, the extemporaneous preparation of phenytoin suspension is common, but the hot climatic weather in Saudi Arabia possesses stability problems that should be tackled as the prepared suspension should pass all the stability tests to ensure uniform dosage of the extemporaneous formulation. In the current study, the commercial capsules were used to prepare the oral phenytoin sodium extemporaneous suspension. The physical, chemical and microbiological stability of phenytoin sodium suspension is analyzed at various temperatures.</span> 展开更多
关键词 Physical Stability PHENYTOIN Extemporaneous Preparation Chemical Stability EPILEPSY
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Assessment of Groundwater Quality for Domestic and Irrigation Purposes in Northern Bamenda (Cameroon) 认领
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作者 Alice Magha Margaret Tita Awah +4 位作者 Gus Djibril Kouankap Nono Primus Azinwi Tamfuh Pierre Wotchoko Mercy Adoh Veronique Beyala Kamgang Kabeyene 《水资源与保护(英文)》 2021年第1期1-19,共19页
Safe and reliable drinking water availability constitutes a nightmare in many towns of developing countries and is usually appreciated from its physical appearance without prior knowledge of its chemical and biologica... Safe and reliable drinking water availability constitutes a nightmare in many towns of developing countries and is usually appreciated from its physical appearance without prior knowledge of its chemical and biological properties. This study investigates the suitability of groundwater for domestic and irrigational purposes through physico-chemical and bacteriological analyses in the Northern part of Bamenda Town (Cameroon). Thus, 20 groundwater samples were collected from hand-dug wells and spring sources in September 2018 (rainy season) and February 2019 (dry season) and physico-chemical and bacteriological characteristics were determined. The results revealed that pH ranged from 5.5 to 6.6, thus enabling the classification of the water as slightly acidic. Electrical conductivity varied between 0.01 - 0.06 μS/cm. The relative abundance of ions was such that Ca<sup>2+</sup> > K<sup>+</sup> > Mg<sup>2+</sup> > Na<sup>+</sup> for cations and <span style="white-space:nowrap;">HCO<sup>-</sup><sub style="margin-left:-7px;">3</sub></span> > Cl<sup>-</sup> > <span style="white-space:nowrap;">NO<sup>-</sup><sub style="margin-left:-7px;">3</sub></span> > <span style="white-space:nowrap;">SO<sup>-</sup><sub style="margin-left:-7px;">4</sub></span> for anions. The water types were Ca-Mg-NO<sub>3</sub> in both dry and rainy seasons. The results revealed that the mechanisms controlling groundwater chemistry are rock weathering and atmospheric precipitation. Indicator bacteria such as <em>E. coli</em>, <em>Shigella</em>, <em>Enterobacteria</em>, <em>Vibrio</em>, <em>Streptococcus</em> and <em>Staphylococcus</em> were detected in the studied groundwater samples, thus the water sources may pose a threat to public health. 展开更多
关键词 Reliable Drinking Water Groundwater Quality Spring Sources Chemical Characteristics Bacteriological Characteristics
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New Approach to Deep Miniaturization: A Way to Overcoming Moore’s Law 认领
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作者 Maria K. Koleva 《现代物理(英文)》 2021年第3期167-178,共12页
The matter about some far-going consequences commencing from the replacement of one of the basic principles of the traditional physics that is the principle of locality, with the recently put forward principle of boun... The matter about some far-going consequences commencing from the replacement of one of the basic principles of the traditional physics that is the principle of locality, with the recently put forward principle of boundedness is considered. It is proven that the thermodynamic theory which is explicitly grounded on the principle of locality, suffers inherent contradiction which roots lay down to the principle of locality. The way to overcome it goes via the replacement of the principle of locality with the recently put forward by the author principle of boundedness. In turn, the latter gives rise not only to a fundamentally novel notion for a number of ideas but also it yields replacement of the proportionality between the software and hardware components with a new non-extensive approach to the matter. It is proven that the famous Moore’s law stands in new reading both in its support and the way to overcome its limitations. Apart from its role for the technical applications, the present considerations stand also as a methodological example how the role of the basics of any theory affects practical rules such as the Moore’s law. 展开更多
关键词 Principle of Locality Principle of Boundedness Moore’s Law Decomposition Theorem Chemical Potential Semantic Intelligence
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Chemical Composition and Biological Significance of Thymol as Antiparasitic 认领
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作者 Wafaa M. Hikal Kirill G. Tkachenko +4 位作者 Hussein A. H. Said-Al Ahl Hoda Sany Ali S. Sabra Rowida S. Baeshen Amra Bratovcic 《生态学期刊(英文)》 2021年第3期240-266,共27页
Thymol is one of the most important phytochemical components because of its pharmacological and bioactive potential effects. This review focuses particularly on thymol as an alternative natural antiparasitic with pote... Thymol is one of the most important phytochemical components because of its pharmacological and bioactive potential effects. This review focuses particularly on thymol as an alternative natural antiparasitic with potential use in the pharmaceutical industry. This is in line with the preferences of the natural products for treatment being safer and without side effects. The biosynthesis pathways of thymol and carvacrol have been discussed, and mechanism of action of thymol on parasites. Studies on thymol confirmed the activity of thymol as anti-parasite against anthelmintic, <em>Trypanosoma</em> ssp., <em>Toxoplasma gondii</em>, <em>Leishmania</em> spp., <em>Plasmodium falciparum</em>, <em>Giardia duodenalis</em>, <em>Eimeria</em> ssp., <em>Cryptosporidium baileyi </em>and<em> Cryptosporidium galli</em>. 展开更多
关键词 THYMOL Chemical Composition Biological Activity ANTIPARASITIC
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Phytochemical Profile and <i>In Vitro</i>Antioxidant Properties of Essential Oils from Powder Fractions of <i>Eucalyptus camaldulensis</i>Leaves 认领
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作者 Venant Donald Noumi Richard Marcel Nguimbou +6 位作者 Marthe Valentine Tsague Markusse Deli Sandrine Rup-Jacques Dicko Amadou Elie Njantou Baudelaire Selestin Sokeng Nicolas Yanou Njintang 《美国植物学期刊(英文)》 2021年第3期329-346,共18页
Dried leaves of <i><span style="font-family:Verdana;">Eucalyptus</span></i> <i><span style="font-family:Verdana;">camaldulensis</span></i><span st... Dried leaves of <i><span style="font-family:Verdana;">Eucalyptus</span></i> <i><span style="font-family:Verdana;">camaldulensis</span></i><span style="font-family:Verdana;"> were finely grinded and fractionated</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> by sieving into four granulometric classes (<100 μm, 100 - 200 μm, 200 - 355 μm and >355 μm). The obtained powder fractions were used for essential oil (EO) extraction by hydrodistillation and their phytochemical profile and </span><i><span style="font-family:Verdana;">in</span></i> <i><span style="font-family:Verdana;">vitro</span></i><span style="font-family:Verdana;"> antioxidant activities were evaluated. The mother powder (unsieved powder) was used for comparison. Particle size exerted a significant influence (</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> < 0.05) on the phytochemical composition and </span><i><span style="font-family:Verdana;">in</span></i> <i><span style="font-family:Verdana;">vitro</span></i><span style="font-family:Verdana;"> antioxidant prop</span><span><span style="font-family:Verdana;">erties of the EOs. Comparatively, the mother powder had the highest contents of </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-pinene (55.6%), camphene (3.4%) and limonene (3.7%), while 1,8-cineole (26.6% and 22.4%), </span></span><span style="font-family:Verdana;">exo-fenchol (5.6% and 3.5%), </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-campholenol (4.2% and 3.4%), L-trans-pinocarveol (5.5% and 2.7%), L-borneol (12.6% and 6.8%) and </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-terpineol (16.4% and 7.6%) are the main compounds of EOs from the <100 μm and 100 - 200 μm fractions, respectively. The antioxidant activities of the EOs revealed higher radical-scavenging activities DPPH (90.62% and 70.46%) and ABTS (89.59% and 73.31%) for 展开更多
关键词 Eucalyptus camaldulensis Powder Fraction Essential Oil Chemical Composition Antioxidant Activity
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