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Depolymerization of polyamide 6 in hydrophilic ionic liquids 预览
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作者 Akio Kamimura Yuto Shiramatsu Takuji Kawamoto 《绿色能源与环境:英文版》 CSCD 2019年第2期166-170,共5页
Polyamide 6 underwent an efficient depolymerization in hydrophilic ionic liquids under microwave irradiation at 300℃.The depolymerization completed within 60 min.Caprolactam was readily separated by simple extraction... Polyamide 6 underwent an efficient depolymerization in hydrophilic ionic liquids under microwave irradiation at 300℃.The depolymerization completed within 60 min.Caprolactam was readily separated by simple extraction procedure and the ionic liquids were recovered and reused for several times.Addition of catalytic amounts of DMAP(N,N-dimethylaminopyridine)promoted the depolymerization effectively.The present improved procedure provides a method to avoid direct distillation procedure,which consumes energy for the separation of caprolactam from ionic liquids.Although some contamination of ionic liquids was observed,the present procedure provides a new possibility for the use of ionic liquids for plastic chemical recycling from the viewpoint of development of an energy-saving methodology.Use of solubility switchable ionic liquids is also examined to explore a possibility for better separation although depolymerization did not work well. 展开更多
关键词 CHEMICAL RECYCLING Polyamides CHEMICAL conversion IONIC liquids
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Seasonal and reproductive variation in chemical constituents of scent signals in wild giant pandas
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作者 Wenliang Zhou Yonggang Nie +4 位作者 Yibo Hu Ronald R.Swaisgood Yaohua Zhang Dingzhen Liu Fuwen Wei 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第5期648-660,共13页
Seasonally reproducing animals show many behavioral and physiological changes during the mating period, including increased signaling for intrasexual competition and mate attraction. We collected 102 anogenital gland ... Seasonally reproducing animals show many behavioral and physiological changes during the mating period, including increased signaling for intrasexual competition and mate attraction. We collected 102 anogenital gland secretions(AGS) from marking trees in Foping Nature Reserve, and used gas chromatography mass spectrometry to analyze these chemical composition. Of these marks, all but one were from males, confirmed with DNA analysis. We found that several chemical constituents, especially volatile compounds, were present only during the mating season and that the relative abundance of many compounds changed as a function of breeding season, whereas nonvolatile compounds were lower in the mating season. This seasonal variation in chemical composition of AGS most likely plays an important role in governing giant panda reproduction, including mate location, attraction, and male-male competition. The chemical properties of many of these putative chemosignals—such as volatility and longevity—are suggestive of these roles, and undoubtedly contribute to successful reproduction for this species with a characteristically sophisticated chemical communication system. We also found a number of important differences between the chemical constituents of AGS from wild pandas and those found in previous studies with captive pandas, suggesting that inappropriate chemosignal composition may contribute to poor reproductive success in captive breeding programs. 展开更多
关键词 giant panda CHEMICAL communication anogenital GLAND SECRETIONS CHEMICAL composition reproduction
A multi-channel chemical sensor and its application in detecting hydrothermal vents 预览
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作者 Zhen Cai A J Mur Luis +3 位作者 Jiwan Han Kui Wang Huawei Qin Ying Ye 《海洋学报:英文版》 SCIE CAS CSCD 2019年第9期128-134,共7页
There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-cha... There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-channel chemical sensor to detect such anomalies which can be used in deep-sea at depths of more than 4 000 m. The design allowed five all-solid-state electrodes to be mounted on it and each (apart from one reference electrode) could be changed according to chemicals to be measured. Two experiments were conducted using the chemical sensors. The first was a shallow-sea trial which included sample measurements and in situ monitoring. pH, Eh, CO3^2- and SO4^2- electrodes were utilized to demonstrate that the chemical sensor was accurate and stable outside the laboratory. In the second experiment, the chemical sensor was integrated with pH, Eh, CO3^2- and H2S electrodes, and was used in 29 scans of the seabed along the Southwest Indian Ridge (SWIR) to detect hydrothermal vents, from which 27 sets of valid data were obtained. Hydrothermal vents were identified by analyzing the chemical anomalies, the primary judging criteria were decreasing voltages of Eh and H2S, matched by increasing voltages of pH and CO3^2- . We proposed that simultaneous detection of changes in these parameters will indicate a hydrothermal vent. Amongst the 27 valid sets of data, five potential hydrothermal vents were targeted using the proposed method. We suggest that our sensors could be widely employed by marine scientists. 展开更多
关键词 CHEMICAL sensor MULTI-CHANNEL HYDROTHERMAL VENTS detection CHEMICAL ANOMALIES SWIR
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Effects of Chemical Reactions in the Hypersonic Reacting Flow around Blunt Bodies 预览
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作者 ZHAO Faming WANG Jiangfeng +1 位作者 FAN Xiaofeng YANG Tianpeng 《南京航空航天大学学报:英文版》 EI CSCD 2019年第1期71-79,共9页
The effects of chemical reactions in the hypersonic reacting flow are investigated using an integrated algorithm considering simultaneously two different reaction mechanisms,i.e.,including the high temperature air non... The effects of chemical reactions in the hypersonic reacting flow are investigated using an integrated algorithm considering simultaneously two different reaction mechanisms,i.e.,including the high temperature air non?equilibrium chemical reactions and the H2- air combustion reactions. The program is validated by the air non-equilibrium flow at Mach number of 25.9 with the RAM C-II configuration and the shock-induced combustion flow at Mach number of 4.512 6 around a sphere,respectively. Furthermore,the mixed reacting flow with the Mach number of 10.0 with an opposing jet of hydrogen is numerically analyzed. The results show that the program is reliable,and the effects of chemical reactions engender in the decrease of peak temperature along characteristic lines,as well as on the surface. The production of water is augmented in the region with high ratio of oxygen to hydrogen and weakened in the area with low ratio of oxygen to hydrogen by the air chemical non-equilibrium effects. 展开更多
关键词 HYPERSONIC air CHEMICAL NON-EQUILIBRIUM combustion EFFECTS of CHEMICAL reaction
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Resonant Light Scattering Toward Optical Fiber Humidity Sensors
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作者 Mahboubeh DEHGHANI SANIJ Abolfazl BAHRAMPOUR Ali Reza BAHRAMPOUR 《光子传感器:英文版》 EI CAS CSCD 2019年第1期60-68,共9页
The deposition of tetrakis(4-sulonatophenyl)porphyrin(TPPS)thin film on optical fibers presents many possibilities for sensing applications.The J-form aggregation with a narrow and sharp spectral feature at about 490n... The deposition of tetrakis(4-sulonatophenyl)porphyrin(TPPS)thin film on optical fibers presents many possibilities for sensing applications.The J-form aggregation with a narrow and sharp spectral feature at about 490nm and its sensitivity to humidity have been discussed;a fast change of wavelength occurs according with variation in the humidity level.The reproducibility and high sensitivity of TPPS-coated fibers,along with the capabilities of optical fibers,suggest the device as a good candidate for humidity sensing in harsh environments. 展开更多
关键词 Humidity CHEMICAL porphyrin-based CHEMICAL optical FIBER sensor
门诊药房口服化学药品说明书中有关老年人安全用药标注情况的调查
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作者 鹿华彦 慕文璐 黄琪 《中国校医》 2019年第6期466-468,共3页
目的调查分析本院门诊药房165份口服化学药品说明书中有关老年人用药信息的标注情况,促进老年人合理安全用药。方法由专人负责查阅本院门诊药房正在使用和销售的药品,从中筛选出各类老年人常用口服化学药品说明书165份,收集所有数据,均... 目的调查分析本院门诊药房165份口服化学药品说明书中有关老年人用药信息的标注情况,促进老年人合理安全用药。方法由专人负责查阅本院门诊药房正在使用和销售的药品,从中筛选出各类老年人常用口服化学药品说明书165份,收集所有数据,均采用Microsoft Excel2013录入,并作归类分析。结果在调研的165份口服化学药品说明书中,老年人用药信息标准缺失项排列前4位的分别为"药理毒理"(98.79%)、"药物过量"(98.79%)、"禁忌"(98.79%)、"药物相互作用"(98.18%),而未给出任何有关老年人用药信息的药品说明书占12.73%。明确给出老年人用药剂量为"老年人用药"项的占49.31%,未准确给出老年人用药剂量"老年人用药"项的占34.72%。无任何"老年人用药"项的占15.97%。结论口服化学药品说明书有关老年人的用药指导信息存在不同程度缺失现象,给临床医师及药师指导老年患者用药参考带来难题,口服化学药品说明书中应完善老年人用药信息,确保老年人安全,有效用药。 展开更多
关键词 老年人 化学 药物口服 说明书 安全用药
Dynamic modifications of biomacromolecules:mechanism and chemical interventions
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作者 Chu Wang Peng Zou +7 位作者 Caiguang Yang Lei Liu Liang Cheng Xiaopeng He Liang Zhang Yan Zhang Hualiang Jiang Peng RChen 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第11期1459-1471,共13页
Biological macromolecules(proteins,nucleic acids,polysaccharides,etc.)are the building blocks of life,which constantly undergo chemical modifications that are often reversible and spatial-temporally regulated.These dy... Biological macromolecules(proteins,nucleic acids,polysaccharides,etc.)are the building blocks of life,which constantly undergo chemical modifications that are often reversible and spatial-temporally regulated.These dynamic properties of chemical modifications play fundamental roles in physiological processes as well as pathological changes of living systems.The Major Research Project(MRP)funded by the National Natural Science Foundation of China(NSFC)—"Dynamic modifications of biomacromolecules:mechanism and chemical interventions"aims to integrate cross-disciplinary approaches at the interface of chemistry,life sciences,medicine,mathematics,material science and information science with the following goals:(i)developing specific labeling techniques and detection methods for dynamic chemical modifications of biomacromolecules,(ii)analyzing the molecular mechanisms and functional relationships of dynamic chemical modifications of biomacromolecules,and(iii)exploring biomacromolecules and small molecule probes as potential drug targets and lead compounds. 展开更多
关键词 chemical biology BIOMACROMOLECULE dynamic modification modification analysis chemical intervention
Application of a novel porous tantalum implant in rabbit anterior lumbar spine fusion model:in vitro and in vivo experiments
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作者 Ming Lu Song Xu +9 位作者 Zi-Xiong Lei Dong LU Wei Cao Marko Huttula Chang-He Hou Shao-Hua Du Wei Chen Shuang-Wu Dai Hao-Miao Li Da-Di Jin 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第1期51-62,共12页
Background Some porous materials have been developed to enhance biologic fusion of the implants to bone in spine fusion surgeries.However,there are several inherent limitations.In this study,a novel biomedical porous ... Background Some porous materials have been developed to enhance biologic fusion of the implants to bone in spine fusion surgeries.However,there are several inherent limitations.In this study,a novel biomedical porous tantalum was applied to in vitro and in vivo experiments to test its biocompatibility and osteocompatibility.Methods Bone marrow-derived mesenchymal stem cells (BMSCs) were cultured on porous tantalum implant.Scanning electron microscope (SEM) and Cell Counting Kit-8 assay were used to evaluate the cell toxicity and biocompatibility.Twenty-four rabbits were performed discectomy only (control group),discectomy with autologous bone implanted (autograft group),and discectomy with porous tantalum implanted (tantalum group) at 3 levels:L3–L4,L4–L5,and L5–L6 in random order.All the 24 rabbits were randomly sacrificed at the different post-operative times (2,4,6,and 12 months;n = 6 at each time point).Histologic examination and micro-computed tomography scans were done to evaluate the fusion process.Comparison of fusion index scores between groups was analyzed using one-way analysis of variance.Other comparisons of numerical variables between groups were made by Student t test.Results All rabbits survived and recovered without any symptoms of nerve injury.Radiographic fusion index scores at 12 months post-operatively between autograft and tantalum groups showed no significant difference (2.89 ± 0.32 vs.2.83 ± 0.38, F= 244.60, P = 0.709).Cell Counting Kit-8 assay showed no significant difference of absorbance values between the leaching liquor group and control group (1.25 ± 0.06 vs.1.23 ± 0.04, t = –0.644, P = 0.545),which indicated the BMSC proliferation without toxicity.SEM images showed that these cells had irregular shapes with long spindles adhered to the surface of tantalum implant.No implant degradation,wear debris,or osteolysis was observed.Histologic results showed solid fusion in the porous tantalum and autologous bone implanted intervertebral spaces.Conclusion This novel porous tantal 展开更多
关键词 Porous TANTALUM ANTERIOR LUMBAR INTERBODY fusion bone INGROWTH chemical vapor deposition three-dimensional KNITTED framework
Resultant gradient information, kinetic energy and molecular virial theorem 预览
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作者 Roman F. Nalewajski 《化学报告(英文)》 2019年第1期22-35,共14页
Resultant gradient-information is introduced and applied to problems in chemical reactivity theory. This local measure of the structural information contained in (complex) wavefunctions of electronic states is related... Resultant gradient-information is introduced and applied to problems in chemical reactivity theory. This local measure of the structural information contained in (complex) wavefunctions of electronic states is related to the system overall kinetic energy combining the modulus (probability) and phase (current) contributions. The grand-ensemble representation of thermodynamic equilibria in open systems demonstrates the physical equivalence of the variational energetic and information principles. It is used and to relate the populational derivatives of ensemble-average functionals in both these representations, which represent reactivity criteria for diagnosing the charge-transfer (CT) phenomena. Their equivalence is demonstrated by using the in situ potential and hardness descriptors to predict the direction and optimum amount of CT. The virial theorem is generalized into thermodynamic quantities and used to extract the kinetic energy component from qualitative energy profiles in the bond-formation and (exo/endo)-ergic reactions. The role of electronic kinetic energy in such chemical processes is reexamined, the virial theorem implications for the Hammond postulate of reactivity theory are explored, and variations of the structural-information in chemical processes are addressed. The maximum thermodynamic information rule is formulated and "production" of the gradient-information in chemical reactions is addressed. The Hammond postulate is shown to be indexed by the geometric derivative of resultant gradient-information at transition-state complex. 展开更多
关键词 bond formation chemical REACTIVITY GRAND ENSEMBLE INFORMATION theory RESULTANT INFORMATION VIRIAL theorem
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Special Issue: In celebration of the 70th anniversary of Dalian Institute of Chemical Physics, Chinese Academy of Sciences 预览
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作者 Xinhe Bao Zhongmin Liu 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第9期I0006-I0007,共2页
Dalian Institute of Chemical Physics(DICP) is a comprehensive chemical engineering research institute with strong international reputation, which has made significant contributions to national economic construction, n... Dalian Institute of Chemical Physics(DICP) is a comprehensive chemical engineering research institute with strong international reputation, which has made significant contributions to national economic construction, national security and the progress of science and technology(S&T). 展开更多
关键词 CHEMICAL ENGINEERING DALIAN SCIENCE and technology
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Effect of air masses motion on the rapid change of aerosols in marine atmosphere
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作者 Jinpei Yan Qi Lin +2 位作者 Miming Zhang Shuhui Zhao Liqi Chen 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第9期217-228,共12页
The impact of air masses motion on marine aerosol properties was investigated using an on-board single particle mass spectrometer(SPAMS) deployed for the determination of single particle size resolved chemical composi... The impact of air masses motion on marine aerosol properties was investigated using an on-board single particle mass spectrometer(SPAMS) deployed for the determination of single particle size resolved chemical composition over Southeast China Sea. Two aerosol blooms(E1 and E2) were observed during the cruise. High average particle number count occurred in E1(7320), followed by E2(5850), which was more than 100–150 times of the average particle number count during normal periods. Particles were classified as four major sources, including continental source, shipping source, marine source, and transport source based on the mass spectral similarity. Transport source was identified as those particles with high particle number count occurred only during aerosol bloom period. Three sub-types of EC-Ca, OC-Ca, and Al-rich were classified as transport source.EC-Ca was the dominant particles of the transport source, accounting for more than 70%of the total particles in aerosol bloom events. A uni-modal size distribution in the size range of 0.1–2.0 μm was observed during normal period, while a bimodal distribution with a tiny mode(<0.3 μm) and a coarse mode between 0.4 and 0.6 μm was present during aerosol bloom. The variation of aerosol source is consistent with air masses back trajectories, for the reason that most of the long-range air trajectories are from the ocean,while short air trajectories originate in the continental regions, which means that air masses have a significant impact on the aerosol physical–chemical properties along their tracks. 展开更多
关键词 Marine AEROSOL Chemical composition Source APPORTIONMENT Air MASSES Single PARTICLE AEROSOL mass spectrometer(SPAMS)
Fabrication and characterization of iron and iron carbide thin films by plasma enhanced pulsed chemical vapor deposition
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作者 胡玉莲 田旭 +4 位作者 樊启鹏 王正铎 刘博文 杨丽珍 刘忠伟 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第10期54-60,共7页
A new pulsed chemical vapor deposition (PCVD) process has been developed to fabricate iron (Fe) and iron carbide (Fe1-xCx) thin films at low temperature range from 150℃ to 230℃. The process employs bis(1,4-di-tert-b... A new pulsed chemical vapor deposition (PCVD) process has been developed to fabricate iron (Fe) and iron carbide (Fe1-xCx) thin films at low temperature range from 150℃ to 230℃. The process employs bis(1,4-di-tert-butyl-1,3-diazabutadienyl)iron(II) as iron source and hydrogen gas or hydrogen plasma as the coreactant. The films deposited with hydrogen gas are demonstrated polycrystalline with body-centered cubic Fe. However, for the films deposited with hydrogen plasma, the amorphous phase of iron carbide is obtained. The influence of the deposition temperature on iron and iron carbide characteristics have been investigated. 展开更多
关键词 Fe and Fe1-xCx FILMS H2 plasma PULSED chemical vapor DEPOSITION
化学检测在环境检测中的应用分析 预览
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作者 陈赐权 《中小企业管理与科技》 2019年第16期177-177,179共2页
随着城市化与工业化的发展,不同地区的环境受到不同程度的污染,世界各国对环境的保护尤其重视,对于工厂排放、汽车排放以及其他排放做了相关制度的要求,判断是否达到排放标准或者评估空气的污染程度需要借助一些专业检测手段来完成,其... 随着城市化与工业化的发展,不同地区的环境受到不同程度的污染,世界各国对环境的保护尤其重视,对于工厂排放、汽车排放以及其他排放做了相关制度的要求,判断是否达到排放标准或者评估空气的污染程度需要借助一些专业检测手段来完成,其中化学检测是基本的又是可应用范围最广的一种手段,无论是大气检测还是水质检测,大多数被检测的对象都是对某些化学元素进行定量。基于此,论文对化学检测在环境检测中的应用进行了分析。 展开更多
关键词 环境 检测 化学 污染物
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Yield and Characterization of the Centesimal Composition of Amazonian Estuarine Fish 预览
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作者 Arllon José dos Santos Dias Nyelle Priscila Brito Facanha +3 位作者 Ed Marcos Homobono da Silva Evlen Tamille Silva do Carmo Charles dos Santos Barros Gabriel Araujo da Silva 《农业科学与技术:B》 2019年第3期175-183,共9页
Fish, as one of the fishery resources, is an important constituent of the diet of the Amazon population, as it is the source of several nutritional components. The present work aimed to characterize the centesimal com... Fish, as one of the fishery resources, is an important constituent of the diet of the Amazon population, as it is the source of several nutritional components. The present work aimed to characterize the centesimal composition of Plagioscion squamosissimus fillet (n = 10) and Macrobrachium amazonicum meat (n = 82), species acquired in the estuarine region of the state of Amapá, Brazil. Carcass yield, as well as protein, water content, lipids and ashes was determined according to the methodologies proposed by the Adolf Lutz Institute, as well as carbohydrate and caloric determinations. The analyses were performed in triplicate per sample. After comparing with the literature, it was possible to conclude that P. squamosissimus presented a fillet yield of 31.11%± 0.61%, high protein content (15.99 ± 1.26 g/100 g) and humidity (79.40 ± 1.10 g/100 g), moderate contents of mineral residues (1.10 ± 0.07 g/100 g) and carbohydrates (0.96 ± 0.90 g/100 g), low lipid contents (2.29 ± 0.65 g/100 g), as well as low caloric values (385,018.12 J/100 g) and M. amazonicum a meat yield of 44.12%± 8.34%, high levels of protein (22.81 ± 1.72 g/100 g), carbohydrates (1.92 ± 1.61 g/100 g) and mineral residues (1.76 ± 0.78 g/100 g), moderate water content (73.38 ± 0.78 g/100 g), low lipid levels (0.43 ± 0.08 g/100 g), as well as low caloric values (440,786.3 J/100 g). The results obtained in this work can serve as a subsidy in nutritional diets for humans, thus allowing an adequate dietary use of these species. 展开更多
关键词 NUTRITIONAL assessment bromatological VARIABLES NUTRITIONAL VALUE chemical parameters of FOOD
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Research review on the main chemical constituents and pharmacological properties of the leaves of Isatis indigotica Fortune 预览
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作者 Wei Hong Yufei Xi +2 位作者 Weiyu Zhou Xiaoxiao Huang Shaojiang Song 《亚洲传统医药》 2019年第5期227-236,共10页
Isatis indigotica Fortune,belonging to Isatis genus of Cruciferae family,is widely used as a common Chinese herbal medicine in folk.As a traditional medicinal agent,a wide spectrum of chemical constituents have been i... Isatis indigotica Fortune,belonging to Isatis genus of Cruciferae family,is widely used as a common Chinese herbal medicine in folk.As a traditional medicinal agent,a wide spectrum of chemical constituents have been isolated from the leaves,including alkaloids,flavonoids,flavonoid glycosides,organic acids and glycosides.The research shows that the leaves had multiple activities and good development prospect,which has attracted a wide range of attention.Hence,this article is presented as a review concentrating on chemical constituents and pharmacological activities of the leaves of I.indigotica Fort.,aiming at supporting practical and useful information for the further research and development of this plant. 展开更多
关键词 LEAVES oflsatis indigotica FORTUNE CHEMICAL constituents PHARMACOLOGICAL effects REVIEW
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Far North salamander Digestive Tract6Of endocrine cells of immune organization Chemical Research 预览
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作者 Xiaoli Zhao 《探索-植物与动物科学》 2019年第1期19-24,共6页
Application protein-Biotin-Peroxidase complex (ABC) Immune organization Chemical Method of Far North salamander (Salamandrella Keyserlingii) Digestive Tract5-Serotonin (5-HT), Gastrin (Gas), Somatostatin (SS), Pancrea... Application protein-Biotin-Peroxidase complex (ABC) Immune organization Chemical Method of Far North salamander (Salamandrella Keyserlingii) Digestive Tract5-Serotonin (5-HT), Gastrin (Gas), Somatostatin (SS), Pancreatic hyperglycemia (GLU), People pancreatic polypeptide (PP) AndP-Material (SP)6Of endocrine cells of distribution for the study. In this paperDuncanMultiple compare the of methods of endocrine cells in the digestive tract of distribution density the statistical analysis. Results display,5-Serotonin cells in digestive tract the parts were distribution, Gastric body (2.80 ± 0.70) And twelve duodenum (2.60 ± 0.75) Distribution density highest pylori minimum (0.85 ± 0.67);Gastrin cells only distribution in small intestine twelve duodenum (1.85 ± 0.75) Density highest;somatostatin cells distribution in esophageal, gastric body, pylorus, twelve duodenum and ileum the parts and pylorus (2.25 ± 0.64) Distribution density highest;pancreatic hyperglycemia of cells I saw in gastric cardia and gastric body people pancreatic polypeptide Cells andP-Material cells in the whole digestive tract were not detection. Various endocrine cells of form diverse was round, oval, cone-shaped and spindle and. Far North salamander digestive tract endocrine cells of this a kind of density distribution and morphology characteristics and other amphibians and Heilongjiang origin far northern salamander compared both common and have difference, the reason may be and species, feeding habits and habitat environment and factors about. 展开更多
关键词 FAR NORTH SALAMANDER DIGESTIVE TRACT ENDOCRINE cells immune organization chemical
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Organocatalytic polymerization
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作者 Cheng-Jian Zhang Xing-Hong Zhang 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第9期1087-1089,共3页
Organocatalysis, defined as the use of small organic molecules for catalyzing chemical transformations, can be traced back more than a century and has become a thriving area over the past 20 years.
关键词 Organocatalytic POLYMERIZATION ORGANIC MOLECULES catalyzing CHEMICAL TRANSFORMATIONS
Chemical constituents and pharmacological properties of Sarcandra glabra(Thunb.)Nakai. 预览
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作者 Hao Zhang Peng Zhao +2 位作者 Yangyang Zhang Xiaoxiao Huang Shaojiang Song 《亚洲传统医药》 2019年第5期237-246,共10页
Sarcandra glabra(Thunb.)Nakai.,belonging to Chloranthaceae genus of Sarcandra family,is widely used as the common Chinese herbal medicine in folk.As a traditional medicinal agent,a wide spectrum of chemical constituen... Sarcandra glabra(Thunb.)Nakai.,belonging to Chloranthaceae genus of Sarcandra family,is widely used as the common Chinese herbal medicine in folk.As a traditional medicinal agent,a wide spectrum of chemical constituents have been isolated from the S.glabra,including sesquiterpenoids,triperpenoids,flavonoids,coumarins,phenolic acids and volatile oil.Modern pharmacological studies have shown that S.glabra has many biological activities such as anti-cancer,hepatoprotective activity,anti-inflammatory and anti-asthmatic activities.For the further development of this plant,the primary chemical constitutions of S.glabra and their activities have been summarized in this study. 展开更多
关键词 Sarcandra glabra(Thunb.)Nakai. CHEMICAL constituents PHARMACOLOGICAL ACTIVITIES REVIEW
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Environmental Arsenic and Selenium Contamination and Approaches Towards Its Bioremediation Through the Exploration of Microbial Adaptations: A Review
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作者 Tanmoy PAUL Nimai Chandra SAHA 《土壤圈:英文版》 SCIE CAS CSCD 2019年第5期554-568,共15页
Bioaccumulation of selenium and arsenic resulting from geogenic activities and aggravated by anthropogenic actions has now become a serious environmental issue. Different parts of the world are experiencing issues of ... Bioaccumulation of selenium and arsenic resulting from geogenic activities and aggravated by anthropogenic actions has now become a serious environmental issue. Different parts of the world are experiencing issues of selenium and arsenic contamination, especially in soil and ground water. The present selenium and arsenic contamination scenario has been well represented in contemporary literature, and there are an array of remediation techniques targeting the decontamination of environmental contamination. The use of microbe-mediated remediation of selenium and arsenic contamination is gaining scientific attention for sustainable environmental bioremediation. The present review elucidates the different aspects of selenium and arsenic contamination, bioaccumulation, and bioremediation with implications for successful decontamination of these heavy metals. 展开更多
关键词 BIOACCUMULATION BIOGEOCHEMISTRY chemical species CONTAMINANT DECONTAMINATION heavy metal MICROBIAL remediation microorganism
Promoted conversion of polysulfides by MoO2 inlaid ordered mesoporous carbons towards high performance lithium-sulfur batteries
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作者 Yawei Chen Shuzhang Niu +2 位作者 Wei Lv Chen Zhang Quanhong Yang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期521-524,共4页
As polar materials, transition-metal oxides have shown great potentials to improve the adsorption of lithium polysulfides in lithium-sulfur batteries. Herein, a MoO2-ordered mesoporous carbon (M-OMC)hybrid was designe... As polar materials, transition-metal oxides have shown great potentials to improve the adsorption of lithium polysulfides in lithium-sulfur batteries. Herein, a MoO2-ordered mesoporous carbon (M-OMC)hybrid was designed as the sulfur host, in which MoO2 is inlaid on the surface of ordered mesoporous carbons that can store active materials and provide fast electron transfer channel due to its ordered pore structure. The MoO2 can effectively prevent the migration of polysulfides through the chemical adsorption and promote the conversion of polysulfides towards Li-sulfur battery. 展开更多
关键词 Lithium-sulfur BATTERIES Ordered MESOPOROUS carbon Electron transportation Chemical adsorption Catalytic effect POLYSULFIDES SHUTTLING
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