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Aggregation-induced Emission-active Hyperbranched Poly(tetrahydropyrimidine)s Synthesized from Multicomponent Tandem Polymerization
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作者 Yuzhang Huang Ping Chen +2 位作者 Bo Wei Rongrong Hu Ben Zhong Tang 《高分子科学:英文版》 SCIE CAS CSCD 2019年第4期428-436,I0008共10页
Hyperbranched polymer with highly branched three-dimensional topological structure, a large number of end groups, and multifaceted functionalities have gained much attention, while polymers with aggregation-induced em... Hyperbranched polymer with highly branched three-dimensional topological structure, a large number of end groups, and multifaceted functionalities have gained much attention, while polymers with aggregation-induced emission(AIE) properties become a group of popular luminescent materials recently. The design and synthesis of AIE-active hyperbranched polymers, which combine the advantages of these two types of materials, are attractive but challenging. In this work, four hyperbranched poly(tetrahydropyrimidine)s were synthesized from the metal-free room temperature multicomponent tandem polymerization of diester group-activated internal alkyne,polyfunctional aromatic amines, and formaldehyde in methanol under the catalysis of acetic acid. Through different monomer combination and controlling the monomer loading order, hyperbranched polymers with various topological structures as well as sequences of different functional groups in the polymer backbone were obtained with high molecular weights(up to 3.0 × 10~4 g/mol) in high yields(up to 98%). The hyperbranched poly(tetrahydropyrimidine) emitted faintly in solution, while its luminescence was notably enhanced in the aggregated state, suggesting its typical aggregation-induced emission property. It is anticipated that the multicomponent polymerization may provide a synthetic platform for the construction of hyperbranched polyheterocycles with diverse structures and functionalities. 展开更多
关键词 HYPERBRANCHED polymer MULTICOMPONENT TANDEM POLYMERIZATION Aggregation-induced emission Polyheterocycle
基于ADAMS的串联式6自由度平台仿真分析 预览
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作者 邹喜红 王瑞东 +1 位作者 涂国杰 梅亚 《重庆理工大学学报:自然科学》 CAS 北大核心 2019年第5期7-12,共6页
为了确定串联式6自由度平台系统的结构参数,完成实体的搭建,根据机构学原理,在ADAMS中建立了串联式6自由度平台虚拟样机模型,并对其添加运动副约束、驱动和测量函数后进行运动学与动力学仿真,得到各作动器的运动特性与动力特性,为后续... 为了确定串联式6自由度平台系统的结构参数,完成实体的搭建,根据机构学原理,在ADAMS中建立了串联式6自由度平台虚拟样机模型,并对其添加运动副约束、驱动和测量函数后进行运动学与动力学仿真,得到各作动器的运动特性与动力特性,为后续的优化和控制奠定基础,同时为该平台能作为一种电池包道路模拟振动试验台提供参考。 展开更多
关键词 串联式 六自由度平台 ADAMS 运动学 动力学
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超高效液相色谱-质谱联用法同时测定中毒样品中12种鼠药
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作者 刘红河 康莉 +3 位作者 陈裕华 廖仕成 刘桂华 姜杰 《中国职业医学》 CAS 北大核心 2019年第1期92-97,共6页
目的建立超高效液相色谱-质谱联用法同时测定疑似鼠药中毒患者残留食物、呕吐物、洗胃液、血清及尿液中毒鼠强、杀鼠灵和杀鼠迷等12种鼠药的方法。方法采集疑似鼠药中毒患者残留食物、呕吐物、洗胃液、血清及尿液;其中食物、呕吐物、洗... 目的建立超高效液相色谱-质谱联用法同时测定疑似鼠药中毒患者残留食物、呕吐物、洗胃液、血清及尿液中毒鼠强、杀鼠灵和杀鼠迷等12种鼠药的方法。方法采集疑似鼠药中毒患者残留食物、呕吐物、洗胃液、血清及尿液;其中食物、呕吐物、洗胃液和尿液样品中先加入浓度为2 mol/L的乙酸铵,随后加入乙酸乙酯重复提取2次,血清样品加入乙腈进行提取。样品经氮气吹干后,以甲醇∶乙酸铵溶液(60∶40,V/V)溶解,离心取上清液经C18柱分离,标准曲线法定量,采用超高效液相色谱-质谱联用仪检测。结果 12种鼠药在疑似鼠药中毒患者残留食物、呕吐物、洗胃液、血清及尿液的定量范围内线性关系良好,相关系数为0.992 3~0.999 9。方法检出限在食物、呕吐物或洗胃液为0.03~0.14μg/kg,在血清、尿液分别为0.10~0.30和0.02~0.04μg/L。加标回收率为84.4%~114.0%,批内、批间相对标准偏差分别为2.7%~6.2%和2.4%~9.5%。结论本方法操作简单、高效、准确,适用于因误食鼠药或投毒引起的中毒事件的应急处理。 展开更多
关键词 鼠药 毒鼠强 超高效液相色谱 质谱 串联 联用技术 中毒
Trifluoromethyl radical triggered radical cyclization of N-benzoyl ynamides leading to isoindolinones
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作者 Maud Cassé Christian Nisole +5 位作者 Héloise Dossmann Yves Gimbert Jean-Marie Fourquez Laure Haberkorn Cyril Ollivier Louis Fensterbank 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第11期1542-1546,共5页
Under photocatalytic reductive conditions,trifluoromethyl radical addition onto an ynamide followed by cyclization on a benzoyl moiety produces diverse isoindolinone platforms with good yields.The selectivity of the r... Under photocatalytic reductive conditions,trifluoromethyl radical addition onto an ynamide followed by cyclization on a benzoyl moiety produces diverse isoindolinone platforms with good yields.The selectivity of the radical cyclization,N-benzoyl vs.N-benzyl as radical acceptor and the E/Z ratio of isomers have been rationalized by modeling. 展开更多
关键词 YNAMIDES TRIFLUOROMETHYLATION PHOTOCATALYSIS cascade reactions tandem processes isoindolinones modeling
Tandem Approach to Functionalized Pyrrolo[3,4-α]carbazole-1,3-diones via a Pd-catalyzed Indole-to-carbazole Transformation
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作者 GUO Lianghua XU Mei +3 位作者 JIAN Yong LIU Sheng PAN Weidong DUAN Lian 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第4期621-626,共6页
A one-pot and efficient tliree-component reaction of indoles, acrylates and maleimides for the synthesis of pyrrolo[3,4-α]carbazole-1,3-dione derivatives was developed. Three C-C bonds and one ring were created in a ... A one-pot and efficient tliree-component reaction of indoles, acrylates and maleimides for the synthesis of pyrrolo[3,4-α]carbazole-1,3-dione derivatives was developed. Three C-C bonds and one ring were created in a single step via an indole-to-carbazole transformation triggered by Pd(II)-catalyzed direct C3-alkenylation of indoles. 展开更多
关键词 CARBAZOLE One-pot TANDEM REACTION Three-component REACTION Indole-to-carbazole
Tracking the multiple-step formation of an iron(Ⅲ) complex and its application in photodynamic therapy for breast cancer
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作者 Zhong-Hong Zhu Qian Hu +5 位作者 Hui-Ling Pan Yuexing Zhang Haibing Xu Mohamedally Kurmoo Jin Huang Ming-Hua Zeng 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第6期719-726,共8页
A tandem reaction of pyridin-2-ylmethanamine(L1′) with 8-hydroxyquinoline-2-carbaldehyde(HL1) assisted by FeCl3 was observed to give the new nitrogen heterocycle HL3(HL3=2-(imidazo[1,5-a]pyridin-3-yl)quinolin-8-ol) a... A tandem reaction of pyridin-2-ylmethanamine(L1′) with 8-hydroxyquinoline-2-carbaldehyde(HL1) assisted by FeCl3 was observed to give the new nitrogen heterocycle HL3(HL3=2-(imidazo[1,5-a]pyridin-3-yl)quinolin-8-ol) as its Fe(Ⅲ) complex,[Fe(L3)Cl2](Fe1). Electrospray ionization mass spectrometry(ESI-MS) reveals its formation involves three steps:(1) coordination of both HL1 and L1′ to Fe,(2) aldehyde-amine coupling, and(3) ring closure. The results of electronic absorption spectroscopy, cyclic voltammetry, and density functional theory(DFT) calculations show the proximity of the optical transition energy to that of the excitation of 3O2 to 1O2, which prompted us to explore its application as a photosensitizer for photodynamic therapy(PDT). Photo-toxicity studies show that Fe1 exhibits the highest anti-proliferation efficiency in human breast cancer MDA-MB-231 cells under light irradiation. Moreover, studies with orthotopic models of breast cancer further expounded the anti-tumor activity of Fe1 with no significant toxicity to other organs and low retention in the body. 展开更多
关键词 TANDEM formation iron(Ⅲ) COMPLEX DFT calculation photodynamic therapy BREAST cancer
Significance of IL-1Ra and IL-6 gene variants in Turkish patients with Crimean-Congo hemorrhagic fever
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作者 Umut Safiye Say Coskun Ayse Feyda Nursal +5 位作者 Ferdi Gunes Ayd?n Rustemoglu Abdullah Yayli Nevin Karakus Huseyin Sener Barut Serbulent Yigit 《亚太热带生物医学杂志:英文版》 CAS 2019年第2期85-90,共6页
Objective: To investigate the association between IL-1 Ra variable number of tandem repeat(rs2234663), IL-6-597 GA(rs1800797), IL-6-572 GC(rs1800796) and the risk of CrimeanCongo hemorrhagic fever(CCHF) in the Turkish... Objective: To investigate the association between IL-1 Ra variable number of tandem repeat(rs2234663), IL-6-597 GA(rs1800797), IL-6-572 GC(rs1800796) and the risk of CrimeanCongo hemorrhagic fever(CCHF) in the Turkish patients. Methods: This study included 50 patients infected with CCHF and 50 healthy controls. These variants were genotyped using polymerase chain reaction and/or restriction fragment length polymorphism method. Results: The distribution of the IL-6-572 GC genotypes and alleles varied significantly between the patients and the controls. The subjects carrying IL-6-572 GC GG genotype and G allele had increased risk of developing CCHF compared to the control group(P=0.006, P=0.014, respectively). IL-6-572 GC GC genotype was higher in the controls than the patients(P=0.006). For the triple genotype combinations, the 1/2-GC-GG genotype combination was detected more frequently in the control group than CCHF patients(P=0.016). IL-6(-572/-597) GG-GG genotype was significantly higher in the patient group(P=0.015), while the GC-GG genotype was significantly lower in the patient group(P=0.005). Additionally, the G-G haplotype was significantly higher in the patient group(P=0.042), whereas C-G was found to be significantly lower in the patients than the control group(P=0.037). Conclusions: The results of this study suggest the IL-6-572 GC variant might be genetic markers of sensitivity to CCHF in the Turkish population and may facilitate greater protection against the disease. 展开更多
关键词 Crimean-Congo HEMORRHAGIC fever IL-1RA IL-6 Variable number of tandem REPEAT -572GC -597GA
Analysis of the binding sites with NL-101 to amino acids and peptides by HPLC/MS/MS
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作者 Lingzi Dai Nian Guo +3 位作者 Yaqin Liu Shanshan Shen Qiufu Ge Yuanjiang Pan 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第1期103-106,共4页
The binding between NL-101, a novel nitrogen mustard anti-cancer drug, with amino acids and peptides has been investigated by high performance liquid chromatography electrospray tandem mass spectrometry(HPLC/ESI-MS/MS... The binding between NL-101, a novel nitrogen mustard anti-cancer drug, with amino acids and peptides has been investigated by high performance liquid chromatography electrospray tandem mass spectrometry(HPLC/ESI-MS/MS). This study offers supporting data of the interaction among drug and amino acids and peptides, which could potentially explain the cytotoxic and mutagenic effects of the drug. Collision-induced dissociation(CID) experiment demonstrated that under the same collision energy, the amino group combined with NL-101 adducts are sensitive and often produce more fragment ions;the carboxyl group combined with NL-101 adducts are hard to break and display fewer fragment ions. In addition, when other group(like sulfhydryl group) of amino acids binds to NL-101, CID spectra show different fragmentation pattern. These differences could display structural information about the drug adducts and be utilized as location of the authentic binding sites. 展开更多
关键词 HIGH-PERFORMANCE liquid chromatography/ TANDEM mass spectrometry NL-101 Amino ACIDS PEPTIDES Binding SITES
Tandem pumping architecture enabled high power random fiberlaser with near-diffraction-limited beam quality
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作者 XU JiangMing YE Jun +5 位作者 ZHOU Pu LENG JinYong XIAO Hu ZHANG HangWei WU Jian CHEN JinBao 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第1期80-86,共7页
In this contribution, we present the tandem pumping avenue leveraged performance scaling of random fiber laser to record 3 kW level with inherent temporal stability and near-diffraction-limited beam quality. The high ... In this contribution, we present the tandem pumping avenue leveraged performance scaling of random fiber laser to record 3 kW level with inherent temporal stability and near-diffraction-limited beam quality. The high power system employs a four-stage master oscillator power amplifier chain. The master oscillator is a half-opened cavity structured random distributed feedback fiber laser centered at 1080 nm and pumped by incoherent amplified spontaneous emission source. Narrowband random laser seed is selected by employing a spectral filtering module with a maximum output power of 1.08 W, full width at half maximum linewidth of 0.47 nm and spectral optical-signal-to-noise ratio of about 42 dB. As to the main amplification stage, for given 104 W pre-amplified random laser seed and 3.61 kW pump laser, an ultimate output power of 3.03 kW can be obtained,corresponding to an optical-to-optical conversion efficiency of 81.05%. Nearly single-transverse-mode amplified random laser can be achieved even at full power level for inherent high thermal modal instability threshold enabled by tandem pumping and inducing bending loss for high-order transverse-mode. Further performance scaling of this high power random laser system, such as power boosting, operation wavelength tuning and linewidth alteration, is the next goal. 展开更多
关键词 RANDOM fiber laser distributed feedback power SCALABILITY TANDEM PUMPING
新型离心机串联模型试验方法及其初步应用研究 预览
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作者 李龙起 李昌林 +3 位作者 何川 邓小雪 张帅 蒋金阳 《水利水电技术》 北大核心 2019年第4期200-204,共5页
为解决以往离心机试验中将大型地质物理模型过渡缩尺时无法与离心加速度相匹配的问题,在综合分析以往离心试验技术的基础上,结合现有离心试验技术的不足,提出新型离心机串联模型试验技术。该技术通过两次量纲变换,即在模型设计阶段,原... 为解决以往离心机试验中将大型地质物理模型过渡缩尺时无法与离心加速度相匹配的问题,在综合分析以往离心试验技术的基础上,结合现有离心试验技术的不足,提出新型离心机串联模型试验技术。该技术通过两次量纲变换,即在模型设计阶段,原型地质体经过第一次量纲变换至常规模型试验尺度(m倍),然后经过第二次量纲变换换算至离心模型试验尺度(n倍),将模型缩小至原来的1/mn。第一次变换将模型进行较大尺度的缩减,因此第二次将其变换至离心试验尺度时将具有较大的灵活度,能够适应承载能力较小的离心机模拟高程较大的地质体的工作特征。此技术实现了将天然地质模型缩尺至离心机试验箱内,并结合弱化岩土力学强度的方法,从而解决大尺度地质结构模型模拟中存在的缩尺困难的问题。结合我国西南某水电站边坡开展了初步验证,结果表明,串联试验理论能较好地满足大型离心机模型试验的要求,可再现大型地质体变形破坏的整个过程,该技术较好地解决了蓄水过程中边坡的变形模拟问题。 展开更多
关键词 离心机 串联 模型试验 相似理论
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The xanthate route to all-carbon quaternary centers
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作者 Béatrice Quiclet-Sire Samir Z.Zard 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第11期1450-1462,共13页
This review discusses the numerous routes to all-carbon quaternary centers based on the unique radical chemistry of xanthates. Itsummarizes the various approaches to the synthesis of tertiary xanthates then describes ... This review discusses the numerous routes to all-carbon quaternary centers based on the unique radical chemistry of xanthates. Itsummarizes the various approaches to the synthesis of tertiary xanthates then describes the intra- and intermolecular radicaladditions and combinations thereof that have so far been used to construct quaternary centers. 展开更多
关键词 XANTHATES quaternary centers radical addition CYCLIZATION tandem reactions
An Automatic Solid Phase Extraction and Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry for Determination of Seven Microcystins at Ultra-Trace Levels in Surface Water
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作者 SHEN Fei XU Yanjuan +1 位作者 WANG Ye CHEN Jing 《武汉大学学报:自然科学英文版》 CAS CSCD 2019年第1期30-36,共7页
A method was developed for the detection of seven microcystins(microcystin-LR,RR,YR,LA,LY,LW and LF)in surface water using automatic solid-phase extraction(A-SPE)coupled with ultra-performance liquid chromatography ta... A method was developed for the detection of seven microcystins(microcystin-LR,RR,YR,LA,LY,LW and LF)in surface water using automatic solid-phase extraction(A-SPE)coupled with ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS).The automated solid-phase extraction system was used to extract microcystins(MCs)from water samples.UPLC-MS/MS was used to determine MCs concentrations in just 5 min.Method detection limits were from 0.3 to 0.9 ng/L,microcystin recoveries ranged from 83.8%to 114%,and the relative standard deviation(RSD)varied from 5.6%to 12.5%.This analytical approach was found to be simple,highly sensitive,accurate,which required little manual operation.Additionally,to validate this analytical method,A-SPE+UPLC-MS/MS was applied to characterize the concentration of MCs in Taihu Lake,Wuxi,China. 展开更多
关键词 MICROCYSTINS AUTOMATIC SOLID-PHASE extraction ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS)
Tandem organic light-emitting diodes with buffer-modified C60/ZnPc as charge generation layer
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作者 陈爱 王振 +1 位作者 谢嘉凤 王培 《光电子快报:英文版》 EI 2019年第3期185-189,共5页
In this paper, a significant enhancement in current efficiency of the green tandem organic light-emitting diodes(TOLEDs) is demonstrated, which is based on a buffer-modified charge generation layer(CGL) of fullerene c... In this paper, a significant enhancement in current efficiency of the green tandem organic light-emitting diodes(TOLEDs) is demonstrated, which is based on a buffer-modified charge generation layer(CGL) of fullerene carbon(C60)/zinc-phthalocyanine(ZnPc). Al and MoO3 were used as the buffer-modified layers on both sides of the bilayer C60/ZnPc, respectively. Experimental results show that the inserted Al and MoO3 layers can effectively increase the electron extraction of the CGL for obtaining the device performance enhancement. Compared with that of the green TOLEDs without buffer-modified layers in CGL(37.3 cd·A-1), the current efficiency of the green TOLEDs is increased to 54.1 cd·A-1. Further study results find that the performance can also be improved by optimizing the thickness of Al in the CGL. The maximum current efficiency and maximum luminance of the green TOLEDs achieve 63.5 cd·A-1 and 17 873 cd·m-2, respectively, when the multilayer structure of the CGL is Al(3 nm)/C60(5 nm)/ZnPc(5 nm)/MoO3(3 nm). 展开更多
关键词 TOLED OLEDs CGL TANDEM organic light-emitting diodes with buffer-modified C ZnPc AS charge generation LAYER NPB Al
建立小管网,回收利用汽包连排低温余热 预览
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作者 王峰 《广东化工》 CAS 2019年第5期149-149,148共2页
本文简单介绍了将催化裂化装置各汽包以及锅炉连排水回收,闪蒸之后获得的蒸汽、凝结水,建立了一个0.3 MPa蒸汽和一个低温凝结水伴热两个小管网,充分利用连排水余热,取得了较好的工业应用效果,降低装置能耗2.3 kgEO/t。
关键词 催化裂化 连排 余热
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Characterization and evolutionary dynamics of complex regions in eukaryotic genomes
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作者 José Ranz Bryan Clifton 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第4期467-488,共22页
Complex regions in eukaryotic genomes are typically characterized by duplications of chromosomal stretches that often include one or more genes repeated in a tandem array or in relatively close proximity.Nevertheless,... Complex regions in eukaryotic genomes are typically characterized by duplications of chromosomal stretches that often include one or more genes repeated in a tandem array or in relatively close proximity.Nevertheless,the repetitive nature of these regions,together with the often high sequence identity among repeats,have made complex regions particularly recalcitrant to proper molecular characterization,often being misassembled or completely absent in genome assemblies.This limitation has prevented accurate functional and evolutionary analyses of these regions.This is becoming increasingly relevant as evidence continues to support a central role for complex genomic regions in explaining human disease,developmental innovations,and ecological adaptations across phyla.With the advent of long-read sequencing technologies and suitable assemblers,the development of algorithms that can accommodate sample heterozygosity,and the adoption of a pangenomic-like view of these regions,accurate reconstructions of complex regions are now within reach.These reconstructions will finally allow for accurate functional and evolutionary studies of complex genomic regions,underlying the generation of genotype-phenotype maps of unprecedented resolution. 展开更多
关键词 COMPLEX GENOMIC REGIONS sequencing technologies genome assembly structural variation TANDEM gene duplicates evolutionary NOVELTY
串列式超声检测的应用 预览
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作者 邵文京 《无损检测》 2019年第5期54-55,83共3页
在深水海洋石油平台钢结构中,中厚板的双面焊T型焊接接头容易出现根部的未焊透、未融合、裂纹等垂直于检测面的危害性面状缺陷。用单一斜探头不易发现此类缺陷,容易漏检,尤其是用角度较小的探头检测时。由于串列式超声波检测对垂直性面... 在深水海洋石油平台钢结构中,中厚板的双面焊T型焊接接头容易出现根部的未焊透、未融合、裂纹等垂直于检测面的危害性面状缺陷。用单一斜探头不易发现此类缺陷,容易漏检,尤其是用角度较小的探头检测时。由于串列式超声波检测对垂直性面状缺陷检测效果好,对深水海洋石油平台钢结构中厚板的双面焊T型焊接接头进行了串列式超声检测,结果表明,该方法可作为常规超声检测的一种辅助型检测方法。 展开更多
关键词 超声波检测 串列式 垂直性面状缺陷 T型焊接接头
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High Efficiency and Quality of Multi-Pass Tandem Gas Metal Arc Welding for Thick Al 5083 Alloy Plates
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作者 姜朝 华学明 +3 位作者 黄立进 吴东升 李芳 蔡艳 《上海交通大学学报:英文版》 EI 2019年第2期148-157,共10页
Multi-pass tandem gas metal arc welding(TGMAW) for Al 5083 alloy plates with 30 mm thickness is carried out to study its high efficiency and high quality. The welding process is evaluated by high-speed photographs and... Multi-pass tandem gas metal arc welding(TGMAW) for Al 5083 alloy plates with 30 mm thickness is carried out to study its high efficiency and high quality. The welding process is evaluated by high-speed photographs and electrical signals. The deposition rate and welding time are calculated to characterize the welding efficiency. The bead formation, porosity, microstructure and mechanical properties are tested and analyzed. The results indicate that though arc deflection occurs due to the electromagnetic interference between two arcs during TGMAW process, it does not affect the welding process stability significantly. The deposition rate and welding time of TGMAW process are about 15 g/min larger and about 16.7% less than those of gas metal arc welding(GMAW)process respectively, accompanied by the reduction of heat input. The TGMAW welded joint has less porosity and more refined microstructure to contribute to the improvement of mechanical properties(micro-hardness, tensile strength and ductility). It can be concluded that TGMAW process yields excellent performance of welded joint with improved welding efficiency, which makes it extremely practical during welding of thick plates. 展开更多
关键词 MULTI-PASS WELDING TANDEM gas metal arc welding(TGMAW) WELDING efficiency POROSITY microstructure mechanical property
基于液相色谱-质谱联用技术探索胃癌的糖肽生物分子标志物 预览
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作者 杨楠 范国荣 《药学服务与研究》 CAS 2019年第1期19-24,共6页
目的:探索胃癌病人血清中潜在的N-糖肽生物分子标志物。方法:采用超高效液相色谱串联三重四级杆质谱法(UPLC-QqQ-MS/MS)对胃癌病人和胃炎病人血清中的N-糖肽进行定量分析,通过独立样本t检验与偏最小二乘法(partialleastsquares,PLS)对... 目的:探索胃癌病人血清中潜在的N-糖肽生物分子标志物。方法:采用超高效液相色谱串联三重四级杆质谱法(UPLC-QqQ-MS/MS)对胃癌病人和胃炎病人血清中的N-糖肽进行定量分析,通过独立样本t检验与偏最小二乘法(partialleastsquares,PLS)对数据进行分析。结果:对约60种N-糖肽进行统计分析,找到7个具有显著性差异的N-糖肽,分别为N4400-IgG1、N5400-IgG1、N4410-IgG1、N3500-IgA、N5400-IgA、N5402-IgA和N5501-J。以这7种N-糖肽对测试组进行PLS分析,结果表明胃炎病人和胃癌病人之间已出现一定的分离趋势。结论:本研究发现了胃癌潜在的N-糖肽生物分子标志物。该方法为探索胃癌生物分子标志物提供了有力的技术支持,对胃癌的早期诊断具有重要临床意义。 展开更多
关键词 胃癌 N-糖肽 生物分子标志物 色谱法 高效液相 质谱法 联用
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南五味子低极性化学成分的GC-MS分析 预览
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作者 王瀚萱 郑巍 +3 位作者 董家潇 陈海生 郭良君 金永生 《药学服务与研究》 CAS 2019年第1期25-28,51共5页
目的:研究南五味子中主要的低极性化学成分。方法:用95%乙醇热提取南五味子,提取液用石油醚(沸程60~90℃)萃取得到石油醚部位。采用GC-MS法检测其主要成分,将测定结果与标准谱库对比分析,用峰面积归一法计算各个成分的相对含量。结果:... 目的:研究南五味子中主要的低极性化学成分。方法:用95%乙醇热提取南五味子,提取液用石油醚(沸程60~90℃)萃取得到石油醚部位。采用GC-MS法检测其主要成分,将测定结果与标准谱库对比分析,用峰面积归一法计算各个成分的相对含量。结果:从南五味子石油醚提取部位鉴定出47种化学成分,主要以倍半萜类化合物为主(占82.35%),脂肪酸及其酯类化合物次之(占5.8%)。其中含量最高的两个化合物为喇叭烯氧化物(Ⅱ)(22.71%)和别香橙烯氧化物(Ⅱ)(11.98%)。13种化学成分为首次从该属植物中发现。结论:与水蒸气蒸馏法、超临界CO2提取法、索式提取法相比,采用乙醇提取后石油醚萃取的方法获得的南五味子主要成分基本相同,但含量不同,且本研究提取的成分中脂肪酸和酯类化合物含量较低。 展开更多
关键词 南五味子 低极性化学成分 倍半萜类 色谱法 气相 质谱法 联用
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Tandem Biocatalysis by CotA-TJ102@UIO-66-NH 2 and Novozym 435 for Highly Selective Transformation of HMF into FDCA 预览
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作者 Xin Chang Chengyu Zhang +8 位作者 Lan Gao Xiao Liu Shengping You Wei Qi Kang Wang Xin Guo Rongxin Su Han Lu Zhimin He 《天津大学学报:英文版》 EI CAS 2019年第5期488-496,共9页
2,5-Furandicarboxylic acid (FDCA) is a potential biorenewable chemical for applications including plastics, polyamides, drugs, etc. The selective biosynthesis of FDCA from 5-hydroxymethylfurfural (HMF) by a speci c en... 2,5-Furandicarboxylic acid (FDCA) is a potential biorenewable chemical for applications including plastics, polyamides, drugs, etc. The selective biosynthesis of FDCA from 5-hydroxymethylfurfural (HMF) by a speci c enzyme poses a great challenge. In this study, we reported an e cient strategy to produce FDCA from HMF by the tandem biocatalysis of laccase (CotA-TJ102@UIO-66-NH 2 ) and Novozym 435. For the rst step, a nanoparticle metal organic framework was synthesized as a carrier to immobilize CotA-TJ102@UIO-66-NH 2 , which was assigned for the production of 5-formyl-2-furancarboxylic acid (FFCA) and featured an enzyme loading of 255.54 mg/g, speci c activity of 135.90 U/mg, and solid loading ratio of 99.65%. Under optimal conditions, an ideal FFCA yield of 98.5% was achieved, and the CotA-TJ102@UIO-66-NH2 pre- sented a high recycling capacity after 10 cycles. For the second step, Novozym 435 was applied for the further conversion of FFCA into FDCA, presenting a high FDCA yield of 95.5% under the optimized conditions. Novozym 435 also exhibited a high recyclability after eight cycles. As a result, the tandem biocatalysis strategy provided a 94.2% FDCA yield from HMF, indicating its excellence as a method for FDCA production. 展开更多
关键词 CotA-TJ102@UIO-66-NH 2 Novozym 435 TANDEM BIOCATALYSIS 5-Hydroxymethylfurfural 2 5-Furandicarboxylic acid
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