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Association study on GNB3 gene polymorphism with essential hypertension in Xinjiang Uygur group

JING Jianying, WANG Dan, WANG Xiaofeng, JIN Jianzhong, JIN Li, JIAO Yi, WEN Hao, LIN Renyong

《医学前沿(英文)》 2007年 第1卷 第2期   页码 230-233 doi: 10.1007/s11684-007-0045-z

摘要: The relationship between the tenth exon C825T of G-protein β3 subunit (GNB) genetic polymorphism and hypertension in the Uygur population of China was investigated. A nested case-control study ( = 738) was carried out. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to genotype GNB C825T polymorphism in 354 hypertensive (HT) and 384 normotensive (NT) Uygur subjects. The distributions of GNB C825T genotypes were CC (27.2%), TT (42.9%), and CT (29.9%) in the hypertensive subjects and CC (27.7%), TT (42.4%), CT (29.9%) in the normotensive subjects. There were no significant differences in the genotype distributions between the two groups ( = 0.0262 P = 0.99). The T allele was 51.4% in hypertensive subjects and 51.2% in normotensive subjects, which, between the two groups, was not a significant difference ( = 0.0016 P = 0.97). Further analysis shows that there is no association between C825T genotypes and age, body mass index (BMI), Glucose (GLU), Triglyceride (TG), Cholesterol (CHO), systolic blood pressure (SBP) and diastolic blood pressure (DBP). No evidence was found to suggest an association between GNB C825T polymorphism and hypertension in the Uygur population of China.

关键词: case-control     significant difference     reaction-restriction fragment     C825T polymorphism     evidence    

Current molecular biologic techniques for characterizing environmental microbial community

Dawen GAO, Yu TAO

《环境科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 82-97 doi: 10.1007/s11783-011-0306-6

摘要: Microbes are vital to the earth because of their enormous numbers and instinct function maintaining the natural balance. Since the microbiology was applied in environmental science and engineering more than a century ago, researchers desire for more and more information concerning the microbial spatio-temporal variations in almost every fields from contaminated soil to wastewater treatment plant (WWTP). For the past 30 years, molecular biologic techniques explored for environmental microbial community (EMC) have spanned a broad range of approaches to facilitate the researches with the assistance of computer science: faster, more accurate and more sensitive. In this feature article, we outlined several current and emerging molecular biologic techniques applied in detection of EMC, and presented and assessed in detail the application of three promising tools.

关键词: molecular biological technique     microbial community     denaturing gradient gel electrophoresis (DGGE)     terminal restriction fragment length polymorphism (T-RFLP)     environmental applications    

Diversity and vertical distributions of sediment bacteria in an urban river contaminated by nutrients and heavy metals

Xunan YANG, Shan HUANG, Qunhe WU, Renduo ZHANG, Guangli LIU

《环境科学与工程前沿(英文)》 2013年 第7卷 第6期   页码 851-859 doi: 10.1007/s11783-013-0569-1

摘要: The aim of this study was to investigate the benthic bacterial communities in different depths of an urban river sediment accumulated with high concentrations of nutrients and metals. Vertical distributions of bacterial operational taxonomic units (OTUs) and chemical parameters (nutrients: , , dissolved organic carbon, and acid volatile sulfur; metals: Fe, Zn, and Cu) were characterized in 30 cm sediment cores. The bacterial OTUs were measured using the terminal restriction fragment length polymorphism analysis. Biodiversity indexes and multivariate statistical analyses were used to characterize the spatial distributions of microbial diversity in response to the environmental parameters. Results showed that concentrations of the nutrients and metals in this river sediment were higher than those in similar studies. Furthermore, high microbial richness and diversity appeared in the sediment. The diversity did not vary obviously in the whole sediment profile. The change of the diversity indexes and the affiliations of the OTUs showed that the top layer had different bacterial community structure from deeper layers due to the hydrological disturbance and redox change in the surface sediment. The dominant bacterial OTUs ubiquitously existed in the deeper sediment layers (5–27 cm) corresponding to the distributions of the nutrients and metals. With much higher diversity than the dominant OTUs, the minor bacterial assemblages varied with depths, which might be affected by the sedimentation process and the environmental competition pressure.

关键词: heavy metals     nutrients     sediment profile     terminal restriction fragment length polymorphism    

Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

《环境科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 194-199 doi: 10.1007/s11783-009-0018-3

摘要: Four typical coastal sites (rocky shore, sandy shore, mud flat shore, and artificial harbor) at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial communities. This was accomplished by using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S rDNA fragments. Two kinds of tetrameric restriction enzymes, I and I, were used in the experiment to depict the bacterial community diversity in different marine environments. It was found that the community compositions digested by the two enzymes separately were different. However, the results of bacterial community diversity derived from them were similar. The MDA analysis results of T-RFLP profiles coming from I and I both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four locations. With I as the sample, the pair wise -tests also revealed that variations were minor between each pair of marine environments, with ranging from 0.198 to 0.349. However, the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites ( ranging from 0.282 to 0.349).

关键词: terminal restriction fragment length polymorphism (T-RFLP)     bacterial community structure     marine microbial diversity     HhaI     MspI    

Response of bacterial communities to short-term pyrene exposure in red soil

Jingjing PENG, Hong LI, Jianqiang SU, Qiufang ZHANG, Junpeng RUI, Chao CAI

《环境科学与工程前沿(英文)》 2013年 第7卷 第4期   页码 559-567 doi: 10.1007/s11783-013-0501-8

摘要: Pyrene, a representative polycyclic aromatic hydrocarbon (PAH) compound produced mainly from incomplete combustion of fossil fuels, is hazardous to ecosystem health. However, long-term exposure studies did not detect any significant effects of pyrene on soil microorganism. In this study, short-term microcosm experiments were conducted to identify the immediate effect of pyrene on soil bacterial communities. A freshly-collected pristine red soil was spiked with pyrene at 0, 10, 100, 200, and 500 mg·kg and incubated for one day and seven days. The bacterial communities in the incubated soils were analyzed using 16S rRNA sequencing and terminal restriction fragment length polymorphism (T-RFLP) methods. The results revealed high bacterial diversity in both unspiked and pyrene-spiked soils. Only at the highest pyrene-spiking rate of 500 mg·kg , two minor bacteria groups of the identified 14 most abundant bacteria groups were completely suppressed. Short-term exposure to pyrene resulted in dominance of Proteobacteria in soil, followed by Acidobacteria, Firmutes, and Bacteroidetes. Our findings showed that bacterial community structure did respond to the presence of pyrene but recovered rapidly from the perturbation. The intensity of impact and the rate of recovery showed some pyrene dosage-dependent trends. Our results revealed that different levels of pyrene may affect the bacterial community structure by suppressing or selecting certain groups of bacteria. It was also found that the bacterial community was most susceptible to pyrene within one day of the chemical addition.

关键词: pyrene     bacterial communities     terminal restriction fragment length polymorphism     short-term exposure     rank-abundance plots    

Community dynamics of ammonia oxidizing bacteria in a full-scale wastewater treatment system with nitrification stability

Xiaohui WANG, Xianghua WEN, Hengjing YAN, Kun DING, Man HU

《环境科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 92-98 doi: 10.1007/s11783-010-0254-6

摘要: To determine whether the functional stability of nitrification was correlated to a stable community structure of ammonia oxidizing bacteria (AOB) in a full-scale wastewater treatment plant, the AOB community dynamics in a wastewater treatment system was monitored over one year. The community dynamics were investigated using specific PCR followed by terminal restriction fragment length polymorphism (T-RFLP) analysis of the gene. The T-RFLP results indicated that during the period of nitrification stability, the AOB community structure in the full-scale wastewater treatment system was relatively stable, and the average change rate every 15 d of the system was 6.6%±5.8%. The phylogenetic analysis of the cloned gene showed clearly that the dominant AOB in the system was spp. The results of this study indicated that throughout the study period, the AOB community structure was relatively stable in the full-scale wastewater treatment system with functional stability of nitrification.

关键词: ammonia-oxidizing bacteria (AOB)     community dynamics     terminal restriction fragment length polymorphism (T-RFLP)     nitrification performance    

Calorie restriction and its impact on gut microbial composition and global metabolism

Xiaojiao Zheng, Shouli Wang, Wei Jia

《医学前沿(英文)》 2018年 第12卷 第6期   页码 634-644 doi: 10.1007/s11684-018-0670-8

摘要:

Calorie restriction (CR) is a dietary regimen that reduces calorie intake without incurring malnutrition or a reduction in essential nutrients. It has long been recognized as a natural strategy for promoting health, extending longevity, and prevents the development of metabolic and age-related diseases. In the present review, we focus on the general effect of CR on gut microbiota composition and global metabolism. We also propose mechanisms for its beneficial effect. Results showed that probiotic and butyrate-producing microbes increased their relative abundance, whereas proinflammatory strains exhibited suppressed relative abundance following CR. Analyses of the gut microbial and host metabolisms revealed that most host microbial co-metabolites were changed due to CR. Examples of dramatic CR-induced changes in host metabolism included a decrease in the rate of lipid biosynthesis and an increase in the rates of fatty acid catabolism, β-oxidation, glycogenolysis, and gluconeogenesis. The observed phenotypes and the further verification of the direct link between gut microbiota and metabolome may benefit patients that are at risk for developing metabolic disease. Thus, improved gut microbiota composition and metabolome are potential biomarkers for determining the effectiveness of dietary interventions for age-related and metabolic diseases.

关键词: caloric restriction     gut microbiota     metabolome    

CD176 single-chain variable antibody fragment inhibits the adhesion of cancer cells to endothelial cells

null

《医学前沿(英文)》 2016年 第10卷 第2期   页码 204-211 doi: 10.1007/s11684-016-0443-1

摘要:

CD176 (Thomsen-Friedenreich antigen) is a tumor-associated carbohydrate epitope (glycotope) functionally involved in blood spread and liver metastasis of cancer cells by mediating the adhesion of cancer cells to endothelial cells and hepatocytes, respectively. CD176 could be a promising target for antitumor immunotherapy. We applied B lymphocytes obtained from mice immunized with CD176 antigen and constructed a phage display library. A positive clone of CD176 single-chain variable antibody fragment (scFv) was successfully screened from this library. The CD176 scFv was expressed in Escherichia coli and purified. The purified scFv can bind to the natural CD176 expressed on the surface of cancer cells. Furthermore, the CD176 scFv inhibits the adhesion of CD176+ cancer cells to endothelial cells and hepatocytes. This CD176 scFv provides a basis for future development of recombinant CD176-specific antibodies that can be used in therapeutic application.

关键词: CD176     Thomsen-Friedenreich antigen     scFv     cancer     therapy     adhesion     metastasis    

Proteomics study of Mycoplasma pneumoniae pneumonia reveals the Fc fragment of the IgG-binding protein

《医学前沿(英文)》 2022年 第16卷 第3期   页码 378-388 doi: 10.1007/s11684-021-0840-y

摘要: Macrolide and corticosteroid resistance has been reported in patients with Mycoplasma pneumoniae (MP) pneumonia (MPP). MP clearance is difficult to achieve through antibiotic treatment in sensitive patients with severe MPP (SMPP). SMPP in children might progress to airway remodeling and even bronchiolitis/bronchitis obliterans. Therefore, identifying serum biomarkers that indicate MPP progression and exploring new targeted drugs for SMPP treatment require urgency. In this study, serum samples were collected from patients with general MPP (GMPP) and SMPP to conduct proteomics profiling. The Fc fragment of the IgG-binding protein (FCGBP) was identified as the most promising indicator of SMPP. Biological enrichment analysis indicated uncontrolled inflammation in SMPP. ELISA results proved that the FCGBP level in patients with SMPP was substantially higher than that in patients with GMPP. Furthermore, the FCGBP levels showed a decreasing trend in patients with GMPP but the opposite trend in patients with SMPP during disease progression. Connectivity map analyses identified 25 possible targeted drugs for SMPP treatment. Among them, a mechanistic target of rapamycin kinase (mTOR) inhibitor, which is a macrolide compound and a cell proliferation inhibitor, was the most promising candidate for targeting SMPP. To our knowledge, this study was the first proteomics-based characterization of patients with SMPP and GMPP.

关键词: severe Mycoplasma pneumoniae pneumonia     children     proteomics     Fc fragment of the IgG-binding protein     mechanistic target of rapamycin kinase inhibitor    

An identification method for enclosed voids restriction in manufacturability design for additive manufacturing

Shutian LIU,Quhao LI,Wenjiong CHEN,Liyong TONG,Gengdong CHENG

《机械工程前沿(英文)》 2015年 第10卷 第2期   页码 126-137 doi: 10.1007/s11465-015-0340-3

摘要:

Additive manufacturing (AM) technologies, such as selective laser sintering (SLS) and fused deposition modeling (FDM), have become the powerful tools for direct manufacturing of complex parts. This breakthrough in manufacturing technology makes the fabrication of new geometrical features and multiple materials possible. Past researches on designs and design methods often focused on how to obtain desired functional performance of the structures or parts, specific manufacturing capabilities as well as manufacturing constraints of AM were neglected. However, the inherent constraints in AM processes should be taken into account in design process. In this paper, the enclosed voids, one type of manufacturing constraints of AM, are investigated. In mathematics, enclosed voids restriction expressed as the solid structure is simply-connected. We propose an equivalent description of simply-connected constraint for avoiding enclosed voids in structures, named as virtual temperature method (VTM). In this method, suppose that the voids in structure are filled with a virtual heating material with high heat conductivity and solid areas are filled with another virtual material with low heat conductivity. Once the enclosed voids exist in structure, the maximum temperature value of structure will be very high. Based upon this method, the simply-connected constraint is equivalent to maximum temperature constraint. And this method can be easily used to formulate the simply-connected constraint in topology optimization. The effectiveness of this description method is illustrated by several examples. Based upon topology optimization, an example of 3D cantilever beam is used to illustrate the trade-off between manufacturability and functionality. Moreover, the three optimized structures are fabricated by FDM technology to indicate further the necessity of considering the simply-connected constraint in design phase for AM.

关键词: additive manufacturing     topology optimization     manufacturability constraints     design for additive manufacturing     simply-connected constraint    

Thermodynamic analysis of reaction pathways and equilibrium yields for catalytic pyrolysis of naphtha

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1700-1712 doi: 10.1007/s11705-022-2207-6

摘要: The chain length and hydrocarbon type significantly affect the production of light olefins during the catalytic pyrolysis of naphtha. Herein, for a better catalyst design and operation parameters optimization, the reaction pathways and equilibrium yields for the catalytic pyrolysis of C5–8 n/iso/cyclo-paraffins were analyzed thermodynamically. The results revealed that the thermodynamically favorable reaction pathways for n/iso-paraffins and cyclo-paraffins were the protolytic and hydrogen transfer cracking pathways, respectively. However, the formation of light paraffin severely limits the maximum selectivity toward light olefins. The dehydrogenation cracking pathway of n/iso-paraffins and the protolytic cracking pathway of cyclo-paraffins demonstrated significantly improved selectivity for light olefins. The results are thus useful as a direction for future catalyst improvements, facilitating superior reaction pathways to enhance light olefins. In addition, the equilibrium yield of light olefins increased with increasing the chain length, and the introduction of cyclo-paraffin inhibits the formation of light olefins. High temperatures and low pressures favor the formation of ethylene, and moderate temperatures and low pressures favor the formation of propylene. n-Hexane and cyclohexane mixtures gave maximum ethylene and propylene yield of approximately 49.90% and 55.77%, respectively. This work provides theoretical guidance for the development of superior catalysts and the selection of proper operation parameters for the catalytic pyrolysis of C5–8 n/iso/cyclo-paraffins from a thermodynamic point of view.

关键词: naphtha     catalytic pyrolysis     reaction pathway     equilibrium yield    

催化裂化过程反应化学的进展

许友好,汪燮卿

《中国工程科学》 2007年 第9卷 第8期   页码 6-14

摘要:

面对催化裂化工艺所遇到的挑战,提出了催化裂化过程反应化学的多维反应结构模式。多维反应结构模式的建立是基于对烃类在酸性催化剂上反应化学认识而进行的知识创新,但多维反应结构不同于烃类在酸性催化剂上反应化学。具有多维反应结构的催化裂化工艺更具有多样性和灵活性,基于此已成功地开发了多产异构烷烃的催化裂化工艺和生产清洁汽油和多产丙烯的催化裂化工艺。

关键词: 催化裂化     反应化学     催化剂     多维反应结构     两个反应区    

Heterogeneous reaction mechanism of gaseous HNO

Nan ZHAO,Qingzhu ZHANG,Wenxing WANG

《环境科学与工程前沿(英文)》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0836-z

摘要: We studied the heterogeneous reaction mechanism of gaseous HNO with solid NaCl. HCl is released from heterogeneous reactions between gaseous HNO and solid NaCl. Water molecules induce surface reconstruction of NaCl to facilitate the reaction. Sea salt particles containing NaCl are among the most abundant particulate masses in coastal atmosphere. Reactions involving sea salt particles potentially generate Cl radicals, which are released into coastal atmosphere. Cl radicals play an important role in the nitrogen and O cycles, sulfur chemistry and particle formation in the troposphere of the polluted coastal regions. This paper aimed at the heterogeneous reaction between gaseous HNO and solid NaCl. The mechanism was investigated by density functional theory (DFT). The results imply that water molecules induce the surface reconstruction, which is essential for the heterogeneous reaction. The surface reconstruction on the defective (710) surface has a barrier of 10.24 kcal·mol and is endothermic by 9.69 kcal·mol , whereas the reconstruction on the clean (100) surface has a barrier of 18.46 kcal·mol and is endothermic by 12.96 kcal·mol . The surface reconstruction involved in water-adsorbed (710) surface is more energetically favorable. In comparison, water molecules adsorbed on NaCl (100) surface likely undergo water diffusion or desorption. Further, it reveals that the coordination number of the Cl is reduced after the surface reconstruction, which assists Cl to accept the proton from HNO . HCl is released from heterogeneous reactions between gaseous HNO and solid NaCl and can react with OH free radicals to produce atomic Cl radicals. The results will offer further insights into the impact of gaseous HNO on the air quality of the coastal areas.

关键词: Seasalt particles     NaCl     HNO3     Heterogeneous reaction     Reaction mechanism     Density functional theory    

多维界壳约束下的模糊可拓经济控制

李华,刘峰,贺仲雄

《中国工程科学》 2001年 第3卷 第8期   页码 51-57

摘要:

讨论了复杂大系统,特别是经济系统的智能控制问题,把参与竞争的实体视为模糊可拓经济空间的一个点,把各种限制约束条件视为一个多维界壳,并定义了界壳的约束度。实体在参与竞争时,首先要获取信息,删除噪声,然后寻求界壳与界门,必要时调用可拓力,以达到预定目标。

关键词: 复杂大系统     模糊可拓经济空间     界壳     冲击界门     可拓    

Dual-reaction-center catalytic process continues Fenton’s story

Chao Lu, Kanglan Deng, Chun Hu, Lai Lyu

《环境科学与工程前沿(英文)》 2020年 第14卷 第5期 doi: 10.1007/s11783-020-1261-x

摘要: Abstract • Dual-reaction-center (DRC) system breaks through bottleneck of Fenton reaction. • Utilization of intrinsic electrons of pollutants is realized in DRC system. • DRC catalytic process well continues Fenton’s story. Triggered by global water quality safety issues, the research on wastewater treatment and water purification technology has been greatly developed in recent years. The Fenton technology is particularly powerful due to the rapid attack on pollutants by the generated hydroxyl radicals (•OH). However, both heterogeneous and homogeneous Fenton/Fenton-like technologies follow the classical reaction mechanism, which depends on the oxidation and reduction of the transition metal ions at single sites. So even after a century of development, this reaction still suffers from its inherent bottlenecks in practical application. In recent years, our group has been focusing on studying a novel heterogeneous Fenton catalytic process, and we developed the dual-reaction-center (DRC) system for the first time. In the DRC system, H2O2 and O2 can be efficiently reduced to reactive oxygen species (ROS) in electron-rich centers, while pollutants are captured and oxidized by the electron-deficient centers. The obtained electrons from pollutants are diverted to the electron-rich centers through bonding bridges. This process breaks through the classic Fenton mechanism, and improves the performance and efficiency of pollutant removal in a wide pH range. Here, we provide a brief overview of Fenton’s story and focus on combing the discovery and development of the DRC technology and mechanism in recent years. The construction of the DRC and its performance in the pollutant degradation and interfacial reaction process are described in detail. We look forward to bringing a new perspective to continue Fenton’s story through research and development of DRC technology.

关键词: Dual reaction centers     Fenton     Pollutant utilization     Electron transfer    

标题 作者 时间 类型 操作

Association study on GNB3 gene polymorphism with essential hypertension in Xinjiang Uygur group

JING Jianying, WANG Dan, WANG Xiaofeng, JIN Jianzhong, JIN Li, JIAO Yi, WEN Hao, LIN Renyong

期刊论文

Current molecular biologic techniques for characterizing environmental microbial community

Dawen GAO, Yu TAO

期刊论文

Diversity and vertical distributions of sediment bacteria in an urban river contaminated by nutrients and heavy metals

Xunan YANG, Shan HUANG, Qunhe WU, Renduo ZHANG, Guangli LIU

期刊论文

Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

期刊论文

Response of bacterial communities to short-term pyrene exposure in red soil

Jingjing PENG, Hong LI, Jianqiang SU, Qiufang ZHANG, Junpeng RUI, Chao CAI

期刊论文

Community dynamics of ammonia oxidizing bacteria in a full-scale wastewater treatment system with nitrification stability

Xiaohui WANG, Xianghua WEN, Hengjing YAN, Kun DING, Man HU

期刊论文

Calorie restriction and its impact on gut microbial composition and global metabolism

Xiaojiao Zheng, Shouli Wang, Wei Jia

期刊论文

CD176 single-chain variable antibody fragment inhibits the adhesion of cancer cells to endothelial cells

null

期刊论文

Proteomics study of Mycoplasma pneumoniae pneumonia reveals the Fc fragment of the IgG-binding protein

期刊论文

An identification method for enclosed voids restriction in manufacturability design for additive manufacturing

Shutian LIU,Quhao LI,Wenjiong CHEN,Liyong TONG,Gengdong CHENG

期刊论文

Thermodynamic analysis of reaction pathways and equilibrium yields for catalytic pyrolysis of naphtha

期刊论文

催化裂化过程反应化学的进展

许友好,汪燮卿

期刊论文

Heterogeneous reaction mechanism of gaseous HNO

Nan ZHAO,Qingzhu ZHANG,Wenxing WANG

期刊论文

多维界壳约束下的模糊可拓经济控制

李华,刘峰,贺仲雄

期刊论文

Dual-reaction-center catalytic process continues Fenton’s story

Chao Lu, Kanglan Deng, Chun Hu, Lai Lyu

期刊论文