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Volumetric response of an ellipsoidal liquid inclusion: implications for cell mechanobiology 预览
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作者 Xin Chen Wei He +4 位作者 Shaobao Liu Moxiao Li Guy M. Genin Feng Xu Tian Jian Lu 《力学学报:英文版》 SCIE EI CAS CSCD 2019年第2期338-342,共5页
Elastic composites containing liquid inclusions exist widely in nature and engineering fields. The volumetric response of liquid inclusions is important in many cases, such as an isolated cell embedded in an extracell... Elastic composites containing liquid inclusions exist widely in nature and engineering fields. The volumetric response of liquid inclusions is important in many cases, such as an isolated cell embedded in an extracellular matrix and an oil pocket embedded within shale. In this study, we developed a model for describing the volumetric response of an ellipsoidal liquid inclusion. Specifically, we investigated the volumetric response of an ellipsoidal liquid inclusion embedded in a three-dimensional (3D) matrix through an analytical expression of the volumetric response. We performed parametric analysis and found that loading along the shortest axis can induce the most volume change, while loading along the longest axis can induce the least volume change. We also found that the volumetric response decreases with increasing Poisson ratio of the matrix. These results could be used to understand some cell behavior in a 3D matrix, for example, cell alignment under mechanical load. 展开更多
关键词 LIQUID INCLUSION LIQUID COMPRESSIBILITY INCLUSION theory SOLID-LIQUID interaction
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Determination of bemegride and its Salts in Cosmetics by HPLC and Their Verification by HPLC-MS/MS 预览
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作者 Guo Xiangyu Meng Xianshuang +4 位作者 Bai Hua Ma Qiang Lv Yueguang Chen Meng Wang Chun 《日用化学品科学(英文版)》 2019年第1期68-72,共5页
A high-performance liquid chromatography (HPLC) method has been developed for the determination of bemegride and its salts in cosmetics. A high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) m... A high-performance liquid chromatography (HPLC) method has been developed for the determination of bemegride and its salts in cosmetics. A high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was used for the verification of the analytical results. Cosmetic samples were ultrasonically extracted with methanol, centrifuged and filtered by microporous membrane filter prior to instrumental analysis. The chromatographic separation of the analytes was performed using a Symmetry C18 (4.6 mm × 250 mm, 5 μm) column. The quantitation was carried out by external standard method. The experimental results indicated that the limit of quantitation (LOQ) for bemegride and its salts was 0.5 mg/kg. The mean recoveries at three spiked levels ranged from 85.1% to 107.4% with the relative standard deviations (RSDs) between 3.7% and 9.3%. The suspected positive samples were subjected to further verification by HPLC-MS/ MS. The method is accurate, rapid, sensitive and can be used for the inspection of cosmetics. 展开更多
关键词 COSMETICS bemegride HIGH-PERFORMANCE LIQUID chromatography HIGH-PERFORMANCE LIQUID chromatographytandem mass SPECTROMETRY
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Control performance comparison between tuned liquid damper and tuned liquid column damper using real-time hybrid simulation 预览
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作者 Zhu Fei Wang Jinting +1 位作者 Jin Feng Lu Liqiao 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第3期695-701,共7页
Tuned liquid damper (TLD) and tuned liquid column damper (TLCD) are two types of passive control devices that are widely used in structural control. In this study, a real-time hybrid simulation (RTHS) technique is emp... Tuned liquid damper (TLD) and tuned liquid column damper (TLCD) are two types of passive control devices that are widely used in structural control. In this study, a real-time hybrid simulation (RTHS) technique is employed to investigate the diff erence in control performance between TLD and TLCD. A series of RTHSs is presented with the premise of the same liquid length, mass ratio, and structural parameters. Herein, TLD and TLCD are physically experimented, and controlled structures are numerically simulated. Then, parametric studies are performed to further evaluate the diff erent performance between TLD and TLCD. Experimental results demonstrate that TLD is more eff ective than TLCD under diff erent amplitude excitations. 展开更多
关键词 tuned LIQUID DAMPER tuned LIQUID COLUMN DAMPER REAL-TIME hybrid simulation CONTROL effi ciency structural CONTROL PARAMETRIC study
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A reversed phase/hydrophilic interaction/ion exchange mixed-mode stationary phase for liquid chromatography
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作者 Sainan Zhang Feifang Zhang +1 位作者 Bingcheng Yang Xinmiao Liang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期470-472,共3页
A reversed phase (RP)/hydrophilic interaction (HILIC)/ion exchange (IEX) mixed tri-mode stationary phase (TMSP) has been prepared via a divergent synthesis scheme starting from propylamine on silica then by amine-epox... A reversed phase (RP)/hydrophilic interaction (HILIC)/ion exchange (IEX) mixed tri-mode stationary phase (TMSP) has been prepared via a divergent synthesis scheme starting from propylamine on silica then by amine-epoxy reactions with 1,4-butanedioldiglycidyl ether and tertiary amines (N,Ndimethyldecylamine, DMDA). Its retention mechanism was found to follow RP/HILIC/IEX mixed-mode.The stop-flow test revealed that TMSP had good compatibility with 100% aqueous mobile phase. It demonstrated effective separation towards several kinds of compounds or drug molecules and their counterions within a single run. 展开更多
关键词 MIXED-MODE Stationary PHASE Reversed PHASE LIQUID CHROMATOGRAPHY HYDROPHILIC interaction LIQUID CHROMATOGRAPHY Ion exchange Drug molecules
Immobilization of Functionalized Ionic Liquid on Sol-Gel Derived Silica for Efficient Removal of H2S 预览
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作者 Ma Yunqian Mao Jiaming +2 位作者 Xiao Cong Li Yan Zang Lihua 《中国炼油与石油化工:英文版》 SCIE CAS 2019年第1期62-70,共9页
An innovative approach to H2 S capture has been developed using several metal-based ionic liquids([Bmim]Cl·CuCl2,[Bmim]Cl·FeCl3,[Bmim]Cl·ZnCl2,[Bmim]Br·CuCl2, and [Bmim]Br·FeCl3) immobilized o... An innovative approach to H2 S capture has been developed using several metal-based ionic liquids([Bmim]Cl·CuCl2,[Bmim]Cl·FeCl3,[Bmim]Cl·ZnCl2,[Bmim]Br·CuCl2, and [Bmim]Br·FeCl3) immobilized on the sol-gel derived silica, which is superior to purely viscous ionic liquid with a crucial limit of high temperature, low mass transfer rate,and mass loss. The adsorbents were characterized by the Fourier transform infrared spectrometer, transmission electron microscope, N2 adsorption/desorption, X-ray photoelectron spectroscopy, and thermal analysis techniques. The effects of the metal and halogen in IL, the loading amount of IL, and the adsorption temperature were studied by dynamic adsorption experiments at a gas flow rate of 100 mL/min. The H2 S adsorption results have showed that the optimal adsorbent and adsorption temperature are 5%[Bmim]Cl·CuCl2/silica gel and 20-50 ℃, respectively. H2 S can be captured and oxidized to elemental sulfur, and [Bmim]Cl·CuCl2/silica gel can be readily regenerated by air. The excellent efficiency of H2 S removal may be attributed to the formation of nano-scaled and high-concentration [Bmim]Cl·CuCl2 confined in silica gel, indicating that the immobilization of [Bmim]Cl·CuCl2 on the sol-gel derived silica can be used for H2 S removal promisingly. 展开更多
关键词 FUNCTIONALIZED IONIC LIQUID supported IONIC LIQUID SILICA SOL-GEL H2S removal
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徐州市新生儿丙酸血症筛查与基因突变分析
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作者 王秀利 彭磊 +1 位作者 刘继杰 方媛 《中华新生儿科杂志(中英文)》 CAS 2019年第2期87-92,共6页
目的了解徐州市新生儿丙酸血症的筛查情况、丙酸血症患病率、生化检查结果、基因突变特点及治疗随访情况。方法前瞻性采集2015年9月至2018年9月徐州市活产新生儿血样,应用液相色谱串联质谱技术进行氨基酸和酰基肉碱谱筛查,并结合气相色... 目的了解徐州市新生儿丙酸血症的筛查情况、丙酸血症患病率、生化检查结果、基因突变特点及治疗随访情况。方法前瞻性采集2015年9月至2018年9月徐州市活产新生儿血样,应用液相色谱串联质谱技术进行氨基酸和酰基肉碱谱筛查,并结合气相色谱-质谱技术检测尿有机酸及基因突变分析确诊。对丙酸血症患儿的临床表现、实验室检查、基因突变、治疗及预后进行分析。结果共筛查活产新生儿297 610名,确诊丙酸血症患儿8例,患病率为1∶37 201,其中1例确诊前已发病,表现为反复呕吐、嗜睡、呼吸急促、肌张力低下,7例确诊时无任何临床症状。基因突变分析证实6例为PCCA基因突变,2例为PCCB基因突变。共检出10种PCCA基因突变,包括错义突变5种,剪接突变4种,同义突变1种,其中7种为新突变;4种PCCB基因突变,包括错义突变2种,移码重复突变1种,剪接突变1种,其中3种为新突变。8例丙酸血症患儿中1例因家长拒绝治疗死亡,7例治疗后血丙酰肉碱、丙酰肉碱与乙酰肉碱比值、尿3-羟基丙酸及甲基枸橼酸水平较治疗前显著下降。随访4例生长发育正常,3例出现不同程度的精神运动发育迟缓。结论新生儿疾病筛查对早期确诊丙酸血症至关重要。徐州地区新生儿丙酸血症患病率较高,临床表现以神经系统症状为主,主要病因为PCCA基因缺陷,以错义突变多见。 展开更多
关键词 丙酸血症 色谱法 液相 气相色谱-质谱法 基因突变
同位素稀释液相色谱串联质谱定量检测血清载脂蛋白E及其表型分型的方法学建立
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作者 李卿 居漪 +4 位作者 孙贺伟 范霄宇 张素洁 金中淦 孙立山 《中华检验医学杂志》 CAS CSCD 北大核心 2019年第8期629-633,共5页
目的采用同位素稀释液相色谱串联质谱技术(ID-LC-MS),建立一种对血清载脂蛋白E定量检测并分型的方法.方法方法学建立.以同位素标记精氨酸的肽段为内标,对标本进行变性、烷基化和胰蛋白酶酶解处理,液相色谱部分采用SB-C18色谱柱分离,质... 目的采用同位素稀释液相色谱串联质谱技术(ID-LC-MS),建立一种对血清载脂蛋白E定量检测并分型的方法.方法方法学建立.以同位素标记精氨酸的肽段为内标,对标本进行变性、烷基化和胰蛋白酶酶解处理,液相色谱部分采用SB-C18色谱柱分离,质谱部分采用正离子模式和多反应监测定量和分型.评价该方法的精密度、准确度和线性范围等.收集上海市东方医院2018年10至12月40份血清标本对ID-LC-MS和免疫法进行方法学比较.Deming回归和Bland-Altman分析用于方法学比较.SPSS24软件用于线性评价中的多项式回归分析.结果ApoE的所选酶解肽段在4h内即达释放峰值,SE肽段3h时达到释放峰值.对ApoE分型发现E3/E3、E2/E3和E3/E4型.实验室内不精密度均值为5.2%.低浓度和高浓度准确性评价标本的测定值与靶值的相对偏差分别为7.6%和3.6%.与免疫法比对,Deming回归的截距的95%置信区间为6.44~11.44(P<0.05),斜率的95%置信区间为0.77~0.89(P<0.05),两者的相关性r=0.97.两者差值的均值是-2.95mg/L,95%置信区间为-4.26~1.65mg/L.本方法在16.9~58.5mg/L内呈线性关系.结论本研究建立的ID-LC-MS方法可用于定量血清ApoE,并对ApoE进行蛋白分型. 展开更多
关键词 载脂蛋白E类 表型 色谱法 液相 串联质谱法
Efficiency of Oryza punctata extract on glucose regulation:Inhibition ofα-amylase andα-glucosidase activities 预览
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作者 Balasubramaniam Jaya Prasad Pazhaniyandi Subramania Sharavanan Rengaraj Sivaraj 《粮油科技:英文版》 2019年第2期44-48,共5页
Red rice(Oryza punctata)is a type of unpolished rice which has higher nutritional value compared to white rice or even polished rice.Owing to higher nutritive content and metabolites,dieticians strongly advise red ric... Red rice(Oryza punctata)is a type of unpolished rice which has higher nutritional value compared to white rice or even polished rice.Owing to higher nutritive content and metabolites,dieticians strongly advise red rice for peoples with metabolic disorders including diabetics.However,the mechanism of action and contents of secondary metabolites in Indian red rice variety not reported scientifically.Therefore,the present study aimed to evaluate its mechanism of action through inhibitory effect ofα-amylase andα-glucosidase.Initially,the whole grain of red rice was macerated with methanol at room temperature for 2 weeks.Then,the dried Keywords:and powdered,samples at different concentration(2.5,10,40,and 80μg/mL)were employed to nd out in vitro inhibitory effects onα-amylase andα-glucosidase.In addition,an enzyme kinetics of effective extract was calculated by Line-weaver Burk(LWB)plot analysis.Moreover,the valuable metabolites in the efficient methanolic extract were quantified using high performance liquid chromatog-raphy(HPLC).The results demonstrated that red rice methanolic extract(RRMEt)possess strong inhibitory activity onα-amylase andα-glucosidase compared with acarbose(P<0.01).The IC50 values of RRMEt was found to be 29.7±7.43μg/mL forα-amylase and 20.4±0.25μg/mL forα-glucosidase.LWB indicated that RRMEt is an uncompetitive inhibitor.Further,HPLC analysis revealed protocatechuic acid,catechin,and chlorogenic acids weremore abundant in RRMEt among the fourteen metabolites.We conclude,the efficiency of enzyme inhibition through the influence of phenolic compounds in RRMEt. 展开更多
关键词 Oryza punctata Α-AMYLASE Α-GLUCOSIDASE High performance liquid chromatography (HPLC) Pigmented rice CATECHIN
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应用液相色谱-串联质谱法系统检测糖尿病肾病和糖尿病神经病变患者尿儿茶酚胺水平
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作者 沈莹 罗霞 +2 位作者 管青 孙自镛 程黎明 《中华检验医学杂志》 CAS CSCD 北大核心 2019年第8期645-651,共7页
目的研究尿儿茶酚胺水平与Ⅱ型糖尿病肾病及神经病变的关系.方法病例对照研究.收集华中科技大学同济医学院附属同济医院收治的Ⅱ型糖尿病患者130例(年龄27~81岁,男75例,女55例)和健康对照118名(年龄27~76岁,男67名,女51名)的24h尿液.另... 目的研究尿儿茶酚胺水平与Ⅱ型糖尿病肾病及神经病变的关系.方法病例对照研究.收集华中科技大学同济医学院附属同济医院收治的Ⅱ型糖尿病患者130例(年龄27~81岁,男75例,女55例)和健康对照118名(年龄27~76岁,男67名,女51名)的24h尿液.另收集Ⅱ型糖尿病患者115例(年龄27~77岁,男75例,女40例)和健康对照93名(年龄25~74岁,男57名,女36名)的随机尿.根据尿白蛋白清除率的检测结果,Ⅱ型糖尿病患者分为肾病组(24h尿:37例,随机尿:32例)和非肾病组(24h尿:32例,随机尿:35例);根据问卷调查,定量感觉试验及自主功能试验,Ⅱ型糖尿病患者分为神经病变组(24h尿:31例,随机尿:23例)和非神经病变组(24h尿:30例,随机尿:25例).采用液相色谱-串联质谱法(LC-MS/MS)测定尿儿茶酚胺(CAs)的含量,包括肾上腺素(E)、去甲肾上腺素(NE)、多巴胺(DA)和总儿茶酚胺(总CAs)的含量,并探讨不同分组患者儿茶酚胺的水平.采用χ2检验、独立样本t检验和Mann-Whitney非参数检验对结果进行分析.结果Ⅱ型糖尿病肾病患者24h尿液E(0.74±0.24)μg/24h,NE(9.22±4.02)μg/24h,DA(64.77±21.68)μg/24h和总CAs(74.72±25.65)μg/24h低于非肾病组[E:(4.23±0.50)μg/24h,U=10,P<0.001;NE:(32.31±1.74)μg/24h,t=-2.72,P=0.011;DA:(219.58±27.51)μg/24h,t=-2.88,P=0.007;总CAs:(256.02±30.65)μg/24h,t=-3.02,P=0.005]且差异具有统计学意义(P<0.05).在随机尿液中糖尿病肾病组NE、DA和总CAs含量与非肾病组的差异亦具有统计学意义(P<0.05).结论本研究结果表明糖尿病肾病患者尿儿茶酚胺含量低于非肾病患者,可能与糖尿病肾病的发生发展有关. 展开更多
关键词 糖尿病肾病 糖尿病神经病变 糖尿病 2型 儿茶酚胺类 色谱法 液相 串联质谱法
浸液轴向变速运动黏弹性板的组合参数共振 预览
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作者 张宇飞 刘金堂 闻邦椿 《振动与冲击》 EI CSCD 北大核心 2019年第8期69-74,87共7页
针对浸没于液体中的轴向运动黏弹性板,考虑其速度发生扰动变化,根据经典薄板理论以及达朗贝尔原理,得到该系统的横向振动控制微分方程。假定液体为无黏、无旋、不可压缩的理想流体,流体对板的动压力由板的附加质量来描述。采用多尺度法... 针对浸没于液体中的轴向运动黏弹性板,考虑其速度发生扰动变化,根据经典薄板理论以及达朗贝尔原理,得到该系统的横向振动控制微分方程。假定液体为无黏、无旋、不可压缩的理想流体,流体对板的动压力由板的附加质量来描述。采用多尺度法,分析系统的偏微分方程及边界条件。根据可解性条件及Routh-Hurwitz判据,确定系统和式组合共振与差式组合共振的失稳区域,并讨论不同参数对系统两种组合共振失稳区间的影响。 展开更多
关键词 轴向变速运动板 液体 参数共振 多尺度法 黏弹性
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Wet-spun poly(ionic liquid)-graphene hybrid fibers for high performance all-solid-state flexible supercapacitors 预览
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作者 Karthikeyan Gopalsamy Qiuyan Yang +3 位作者 Shengying Cai Tieqi Huang Zhengguo Gao Chao Gao 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第7期104-110,共7页
It is crucial to develop flexible and wearable electronic devices that have attracted tremendous interest due to their merits on compactness,flexibility and high capacitive properties.Herein we report the continuously... It is crucial to develop flexible and wearable electronic devices that have attracted tremendous interest due to their merits on compactness,flexibility and high capacitive properties.Herein we report the continuously ordered macroscopic poly(ionic liquid)-graphene fibers by wet spinning method via liquid crystal assembly for supercapacitor application.The fabricated all-solid-state supercapacitors exhibited a high areal capacitance(268.2 mF cm 2)and volumetric capacitance(204.6 F cm 3)with an outstanding areal energy density(9.31μWh cm-2)and volumetric energy density(8.28 mWh cm-3).The fiber supercapacitors demonstrated exceptional cycle life for straight electrodes of about 10,000 cycles(94.2%capacitance retention)and flexibility at different angles(0°,45°,90°,180°)along with a good flexible cycling stability after 6000 cycles(92.7%capacitance retention).To date,such a novel poly(ionic liquid)-graphene fiber supercapacitors would be a new platform in real-time flexible electronics. 展开更多
关键词 GRAPHENE fiber Poly(ionic liquid) WET spinning SUPERCAPACITORS Flexibility
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Synthesis of 5-methyl-2-(2,4,4,7-tetramethylchroman-2-yl) Phenol as an Impurity in Thymol 预览
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作者 Yaoyao YANG Kai YU +1 位作者 Yongguang WANG Yuhong YU 《药用植物研究(英文版)》 2019年第1期23-25,共3页
[Objectives] To optimize the preparation process of 5-methyl-2-(2,4,4,7-tetramethylchromanyl) phenol(impurity C) and the liquid phase determination method of the impurity, and to provide an important basis for the est... [Objectives] To optimize the preparation process of 5-methyl-2-(2,4,4,7-tetramethylchromanyl) phenol(impurity C) and the liquid phase determination method of the impurity, and to provide an important basis for the establishment of material methods and quality control of thymol. [Methods] The 4,7-dimethylcoumarin as the starting material was hydrolyzed by potassium hydroxide to obtain the substance II 5-methyl-2-(1-propylene-2-yl) phenol, and then purified and treated with hydrochloric acid to obtain a pale yellow solid. High-purity main peak was obtained by high-performance liquid phase method, and it was identified as impurity C by ~1H-NMR measurement and spectrum analysis. [Results] After the method was optimized, the synthesis route to the impurity C was simple, and the purity of impurity C was high. The obtained impurity C was confirmed by ~1H-NMR to be a compound 5-methyl-2-(2,4,4,7-tetramethylchromanyl) phenol. The liquid phase detection method was successfully established to identify the compound. [Conclusions] The optimized method is easy to control and the impurity C has high purity and it is expected to provide quality assurance for the study of related substances in the quality control of thymol. 展开更多
关键词 THYMOL High performance liquid phase ^1H-NMR
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Choline-based ionic liquids for CO2 capture and conversion
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作者 Ruipeng Li Yanfei Zhao +3 位作者 Zhiyong Li Yunyan Wu Jianji Wang Zhimin Liu 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第2期256-261,共6页
Choline-based ionic liquids(Ch-ILs) with anions possessing interacting sites to attract CO2 were designed, which could capture CO2 with capacity >1.0 mol CO2 per molar IL under ambient conditions. Moreover, this ki... Choline-based ionic liquids(Ch-ILs) with anions possessing interacting sites to attract CO2 were designed, which could capture CO2 with capacity >1.0 mol CO2 per molar IL under ambient conditions. Moreover, this kind of ILs combining with Cu Cl could catalyze the formylation of amines with CO2/H2 at 120 °C. Especially, choline imidazolate showed the best performance,affording a series of N-formamides in excellent yields. It was demonstrated that the IL activated CO2 and the synergistic effect between the IL and Cu Cl resulted in the high activity for catalysing the formylation of amines with CO2/H2. 展开更多
关键词 CHOLINE IONIC LIQUID N-formylation CO2 H2
Tribological performance of tributylmethylammonium bis(trifluoromethylsulfonyl)amide as neat lubricant and as an additive in a polar oil
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作者 Rubén GONZáLEZ Diego RAMOS +4 位作者 David BLANCO Alfonso FERNáNDEZ-GONZáLEZ Jose L.VIESCA Mark HADFIELD Antolin HERNáNDEZ BATTEZ 《摩擦(英文版)》 CSCD 2019年第3期282-288,共7页
The ionic liquid(IL) tributylmethylammonium bis(trifluoromethylsulfonyl)amide([N4441][NTf2]) was used as neat lubricant and as an additive(1.5 wt%) in a polar oil to study its friction and wear reducing properties.Tri... The ionic liquid(IL) tributylmethylammonium bis(trifluoromethylsulfonyl)amide([N4441][NTf2]) was used as neat lubricant and as an additive(1.5 wt%) in a polar oil to study its friction and wear reducing properties.Tribological tests were completed for 90 minutes at room temperature and 100 °C in a reciprocating configuration at loads of 30 and 70 N,10 Hz-frequency,and 4 mm stroke length.Wear volume was measured by confocal microscopy and the surface-IL interaction determined by XPS.The main findings were that neat IL showed the best tribological behavior;the IL-containing mixture behaved similar to the base oil regarding friction,however outperformed the antiwear behavior of the base oil under higher temperature;surface-IL chemical interaction was found mainly at 100 °C. 展开更多
关键词 ionic liquid ADDITIVE friction wear POLAR OIL
AgBF4/[emim][BF4] supported ionic liquid membrane for carbon monoxide/nitrogen separation 预览
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作者 Shichao Feng Yuanyuan Wu +1 位作者 Jianquan Luo Yinhua Wan 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第2期31-39,共9页
In this paper,AgBF4/[emim][BF4] supported ionic liquid membranes(SILMs) were prepared successfully for CO/N2 separation using nitrogen pressure immobilization procedures.The incorporation of AgBF4 could decrease membr... In this paper,AgBF4/[emim][BF4] supported ionic liquid membranes(SILMs) were prepared successfully for CO/N2 separation using nitrogen pressure immobilization procedures.The incorporation of AgBF4 could decrease membrane weight loss,improve the pressure-resistant ability,and keep the critical pressure(0.45 MPa) of the SILMs.The high viscosity and undissolved Ag BF4 solids in membrane liquid would disturb gas molecular transport through membrane and give rise to the gas transport resistance.Therefore,the gas permeability decreased remarkably with increasing AgBF4 carrier content in the membrane.When the molar ratio of AgBF4 to [emim][BF4] increased from 0:1 to 0.3:1,the CO/N2 selectivity of the SILMs showed a great increase from ~1 to ~9 at 20 °C and 0.4 MPa,suggesting that AgBF4 was an effective carrier for CO facilitated transport.The permeabilities of N2 and CO increased at higher transmembrane pressure,indicating that molecular transport would dominate the transport process at high pressure.The temperature-dependent gas permeability followed the Arrhenius equation.Moreover,the differences between the activation energies of CO and N2 became larger after introducing AgBF4,resulting in more obvious decrease in the CO/N2 selectivity at higher operating temperature. 展开更多
关键词 SUPPORTED IONIC liquid membranes [emim][BF4] AgBF4 Carbon MONOXIDE SEPARATION
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Commonalities and characteristics of aqueous extracts from three Uighur medicines were analyzed by using three-stage infrared spectroscopy combined with ultra-performance liquid chromatography-time of flight-mass spectra
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作者 Qu Tiange Zhu Yun +8 位作者 Zhang Ke Huang Jian Wang Hangyu Gao Le Liang Xu Chen Long Wang Jinhui Pang Xiaobo Duan Xingwu 《中医杂志:英文版》 SCIE CAS CSCD 2019年第1期118-126,共9页
OBJECTIVE: To establish a method to analyze the commonalities and characteristics of the aqueous extracts from three Uighur medicines.METHODS: In this study, a combination method of three-stage infrared spectroscopy a... OBJECTIVE: To establish a method to analyze the commonalities and characteristics of the aqueous extracts from three Uighur medicines.METHODS: In this study, a combination method of three-stage infrared spectroscopy and ultra-performance liquid chromatography-time of flight-mass spectra(UPLC-TOF-MS) method was used to analyze the commonalities and characteristics of the aqueous extracts from Hezi(Fructus Chebulae),Maohezi(Terminalia Belliricae Fructus) and Xiqingguo(Chebulae Fructus Immaturus).RESULTS: In Fourier transform-infrared spectroscopy spectra, all three samples showed the characteristic absorption peaks of tannins similarly. According to UPLC-TOF-MS data analysis, the difference of the position and intensity of the peaks at 1713-1707 cm-1 in the three samples were related to the difference in the relative content of tannin and pentacyclic triterpenoids. In second derivative infrared spectroscopy spectra, further analysis of the differences in the infrared spectra of the three samples was performed by increasing the apparent resolution. In combination with UPLC-TOF-MS data, some features infrared absorption peaks were assigned.The absorption peaks at 1032-1030 cm-1 assigned to the stretching vibration of C-O-C(ether bond)groups of tannins;1164-1163, 1063-1062, 1009-1005, 904 cm-1 attributed to the stretching vibration of C-O(ether bond) and C-O-C groups of glycosidic compounds. 1385-1383 cm-1 attributed to the bending vibration of C-H(alkyl hydrogen) of methoxyl group of pentacyclic triterpenoids. Peak 835 cm-1 was assigned to the characteristic absorption peak of bending vibration of = C-H groups of pentacyclic triterpenoids. The two dimensional correlation infrared spectroscopy could further quickly distinguish three samples through the dynamic structural information of their chemical components and discrepancy of auto-peaks and cross-peaks intuitively in the range of 1720-419 cm-1.CONCLUSION: By comparing the intensity of the infrared characteristic absorption peaks, the main chemical components were 展开更多
关键词 TANNINS TERMINALIA Spectrophotometry infrared Chromatography liquid UIGHUR Medicine
Absorption and biotransformation of four compounds in the Guizhi decoction in the gastrointestinal tracts of rats
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作者 Gao Huan Zhang Lishi +1 位作者 Song Jiannan Bai Dong 《中医杂志:英文版》 SCIE CAS CSCD 2019年第3期332-338,共7页
OBJECTIVE:To study the absorption and biotransformation of liquiritin,cinnamic acid,paeoniflorin,and glycyrrhizic acid in the Guizhi decoction (GZD) in the gastrointestinal tracts of rats.METHODS:A simple and reliable... OBJECTIVE:To study the absorption and biotransformation of liquiritin,cinnamic acid,paeoniflorin,and glycyrrhizic acid in the Guizhi decoction (GZD) in the gastrointestinal tracts of rats.METHODS:A simple and reliable high-performance liquid chromatography method was established and validated for the analysis of the four components of GZD simultaneously in the gastrointestinal tracts of rats.Rats were randomly divided into in situ gastrointestinal loop model,in vitro anaerobic culture model,and blank control groups.All rats were fasted for 12 h and anesthetized using 20% urethane.Subsequently,the abdominal cavity of each rat was opened,and the stomach,duodenum,jejunum,ileum,cecum,and colon were ligated.For the in situ gastrointestinal loop model group,2.5 mL of GZD (1.0 g crude drug/mL,37 ℃)were injected into the gastrointestinal tract.The abdominal incision was covered with warm,wet cotton,and animals were maintained at 25 ℃.Then,we collected the gastrointestinal tract content after 1.5 h.For the in vitro anaerobic culture model group,the gastrointestinal tract contents of rats were collected and then cultured in 2.5 mL of GZD in an anaerobic environment at 25 ℃ for 24 h.For the blank control group,rats received the same volume of a normal saline solution instead of GZD.High performance liquid chromatography was used to detect the liquiritin,cinnamic acid,paeoniflorin,and glycyrrhizic acid concentrations in each group and calculate the absorption and biotransformation rates of each ingredient.RESULTS:Cinnamic acid (low polarity) was more easily absorbed by each gastrointestinal part than the higher-polarity glycosides.However,the absorption rate in the cecum was higher than that in other parts.The four compounds,cinnamic acid,liquiritin,paeoniflorin,and glycyrrhizic acid,were transformed completely within 24 h in the cecum and colon,whereas they were hardly transformed in the stomach,excluding glycyrrhizic acid.In addition,all ingredients had higher biotransformation rates in the distal small intestine tha 展开更多
关键词 ABSORPTION CINNAMATES Glycyrrhizic acid BIOTRANSFORMATION Chromatography high pressure liquid Guizhi DECOCTION
液相色谱-串联质谱技术在维生素检测中的应用
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作者 袁小芬 马金飞 +5 位作者 杨青青 刘鹏云 沈凌晓 张前军 李义坤 刘华芬 《中华检验医学杂志》 CAS CSCD 北大核心 2019年第6期479-483,共5页
维生素分为脂溶系列包括ADEK和水溶系列维生素B族及维生素C。目前只有对维生素D、B6、B9及B12开发了传统的免疫学的检测方法,但免疫法无法区分亚型比如维生素D2及D3以及在婴儿中含量较高的Epi同分异构体,因此免疫学方法检测经常会出现... 维生素分为脂溶系列包括ADEK和水溶系列维生素B族及维生素C。目前只有对维生素D、B6、B9及B12开发了传统的免疫学的检测方法,但免疫法无法区分亚型比如维生素D2及D3以及在婴儿中含量较高的Epi同分异构体,因此免疫学方法检测经常会出现假阳性或假阴性。质谱技术以其快速、高分辨率、高灵敏度、高特异性等优点成为生物样本内小分子分析的金标准方法,广泛应用于临床研究及诊断,也为减少样品采集量及一次进样同时检测多种维生素提供了高效方法。 展开更多
关键词 维生素类 色谱法 液相 串联质谱法
高效液相色谱法测定替考拉宁血药浓度及其在重症感染患者中的应用 预览
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作者 晨迪 杨昭毅 +4 位作者 沈爱宗 张圣雨 苏丹 宁丽娟 杨本军 《中国临床保健杂志》 CAS 2019年第5期616-620,共5页
目的建立高效液相色谱法(HPLC)测定替考拉宁血药浓度的方法,为重症感染患者合理使用替考拉宁,制定个体化抗感染给药方案奠定基础。方法建立及采用高效液相色谱法测定重症患者替考拉宁血药浓度,以谷浓度为参考值分析浓度分布情况。结果... 目的建立高效液相色谱法(HPLC)测定替考拉宁血药浓度的方法,为重症感染患者合理使用替考拉宁,制定个体化抗感染给药方案奠定基础。方法建立及采用高效液相色谱法测定重症患者替考拉宁血药浓度,以谷浓度为参考值分析浓度分布情况。结果替考拉宁在3.114~99.650μg/mL范围内线性良好,标准曲线回归方程为y=0.03X+0.004,r=0.9998。批内、批间精密度RSD均小于15%;准确度均在98.26%~111.54%之间,定量下限为3.114μg/mL。共23例患者,46例次监测结果纳入研究;两次采血点的达标率分别为56.52%和47.83%。结论替考拉宁在实际临床中谷浓度达标率低,个体差异大,建议在必要时通过血药浓度监测,使其维持安全有效的血药浓度。 展开更多
关键词 危重病人医疗 血药浓度 色谱法 液相 替考拉宁
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Emergence of superconductivity from fully incoherent normal state in an iron-based superconductor (Ba0.6K0.4)Fe2As2
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作者 Jianwei Huang Lin Zhao +20 位作者 Cong Li Qiang Gao Jing Liu Yong Hu Yu Xu Yongqing Cai Dingsong Wu Ying Ding Cheng Hu Huaxue Zhou Xiaoli Dong Guodong Liu Qingyan Wang Shenjin Zhang Zhimin Wang Fengfeng Zhang Feng Yang Qinjun Peng Zuyan Xu Chuangtian Chen Xingjiang Zhou 《科学通报:英文版》 SCIE EI CSCD 2019年第1期11-19,共9页
In unconventional superconductors,it is generally believed that understanding the physical properties of the normal state is a pre-requisite for understanding the superconductivity mechanism.In conventional supercondu... In unconventional superconductors,it is generally believed that understanding the physical properties of the normal state is a pre-requisite for understanding the superconductivity mechanism.In conventional superconductors like niobium or lead,the normal state is a Fermi liquid with a well-defined Fermi surface and well-defined quasipartcles along the Fermi surface.Superconductivity is realized in this case by the Fermi surface instability in the superconducting state and the formation and condensation of the electron pairs (Cooper pairing).The high temperature cuprate superconductors,on the other hand,represent another extreme case that superconductivity can be realized in the underdoped region where there is neither well-defined Fermi surface due to the pseudogap formation nor quasiparticles near the antinodal regions in the normal state.Here we report a novel scenario that superconductivity is realized in a system with well-defined Fermi surface but without quasiparticles along the Fermi surface in the normal state. High resolution laser-based angle-resolved photoemission measurements have been performed on an optimally-doped iron-based superconductor (Ba0.6K0.4)Fe2As2.We find that,while sharp superconducting coherence peaks emerge in the superconducting state on the hole-like Fermi surface sheets,no quasiparticle peak is present in the normal state.Its electronic behaviours deviate strongly from a Fermi liquid system.The superconducting gap of such a system exhibits an unusual temperature dependence that it is nearly a constant in the superconducting state and abruptly closes at To.These observations have provided a new platform to study unconventional superconductivity in a non-Fermi liquid system. 展开更多
关键词 (Ba0.6K0.4)Fe2As2 ARPES Superconducting gap Normal state Non-Fermi liquid
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