资源类型

期刊论文 31

会议视频 3

年份

2023 1

2022 6

2021 3

2020 2

2019 1

2018 2

2017 2

2016 2

2015 1

2014 1

2013 1

2012 2

2011 1

2010 1

2009 1

2008 1

2007 4

2000 1

1999 1

展开 ︾

关键词

不确定性分析 1

中子俘获疗法 1

中药 1

临床试治 1

交错缠绕 1

代谢组学 1

优快钻井 1

保险费 1

全双层结构 1

农业科学 1

前沿技术与中医药创新发展 1

医学 1

医院中子照射器 1

卡特里娜飓风 1

压力容器技术 1

叶片型面 1

地下水水质 1

垂直钻井 1

复合岩溶 1

展开 ︾

检索范围:

排序: 展示方式:

N-Positive ion activated rapid addition and mitochondrial targeting ratiometric fluorescent probes for in vivo cell H2S imaging

Yan Shi, Fangjun Huo, Yongkang Yue, Caixia Yin

《化学科学与工程前沿(英文)》 2022年 第16卷 第1期   页码 64-71 doi: 10.1007/s11705-021-2048-8

摘要: Heterocyclic compound quinoline and its derivatives exist in natural compounds and have a broad spectrum of biological activity. They play an important role in the design of new structural entities for medical applications. Similarly, indoles and their derivatives are found widely in nature. Amino acids, alkaloids and auxin are all derivatives of indoles, as are dyes, and their condensation with aldehydes makes it easy to construct reaction sites for nucleophilic addition agents. In this work, we combine these two groups organically to construct a rapid response site (within 30 s) for H S, and at the same time, a ratiometric fluorescence response is presented throughout the process of H S detection. As such, the lower detection limit can reach 55.7 nmol/L for H S. In addition, cell imaging shows that this probe can be used for the mitochondrial targeted detection of endogenous and exogenous H S. Finally, this probe application was verified by imaging H S in nude mice.

关键词: heterocyclic compound     hydrogen sulfide     ratiometric     mitochondrial targeted    

Extractive desulfurization of model fuels with a nitrogen-containing heterocyclic ionic liquid

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1735-1742 doi: 10.1007/s11705-022-2167-x

摘要: A nitrogen-containing ionic liquid was synthesized using an aromatic nitrogen-containing heterocyclic and an amino acid, and applied to the extractive desulfurization process to remove benzothiophene, dibenzothiophene, and 4,6-dimethyldibenzothiphene from a model fuel oil. Chemical characterizations and simulation using Gaussian 09 software confirmed the rationality of an ionic liquid structure. Classification of non-covalent interactions between the ionic liquid and the three sulfur-containing contaminants was studied by reduced density gradient analysis. The viscosity of the ionic liquid was adjusted by addition of polyethylene glycol. Under extraction conditions of the volume of ionic liquid to oil as 1:1 and temperature as room temperature, the desulfurization selectivity of ionic liquid followed the order of 4,6-dimethyldibenzothiphene (15 min) < benzothiophene (15 min) ≈ dibenzothiophene (10 min). Addition of p-xylene and cyclohexene to the fuel oil had little effect. The extractant remained stable and effective after multiple regeneration cycles.

关键词: extractive desulfurization     nitrogen-containing heterocyclic ionic liquid     reduced density gradient analysis     desulfurization selectivity    

Steam reforming of toluene as a tar model compound with modified nickel-based catalyst

Omeralfaroug KHALIFA, Mingxin XU, Rongjun ZHANG, Tahir IQBAL, Mingfeng LI, Qiang LU

《能源前沿(英文)》 2022年 第16卷 第3期   页码 492-501 doi: 10.1007/s11708-021-0721-8

摘要: Catalytic steam reforming is a promising route for tar conversion to high energy syngas in the process of biomass gasification. However, the catalyst deactivation caused by the deposition of residual carbon is still a major challenge. In this paper, a modified Ni-based Ni-Co/Al O -CaO (Ni-Co/AC) catalyst and a conventional Ni/Al O (Ni/A) catalyst were prepared and tested for tar catalytic removal in which toluene was selected as the model component. Experiments were conducted to reveal the influences of the reaction temperature and the ratio between steam to carbon on the toluene conversion and the hydrogen yield. The physicochemical properties of the modified Ni-based catalyst were determined by a series of characterization methods. The results indicated that the Ni-Co alloy was determined over the Ni-Co/AC catalyst. The doping of CaO and the presence of Ni-Co alloy promoted the performance of toluene catalytic dissociation over Ni-Co/AC catalyst compared with that over Ni/A catalyst. After testing in steam for 40 h, the carbon conversion over Ni-Co/AC maintained above 86% and its resistance to carbon deposition was superior to Ni/A catalyst.

关键词: catalytic steam reforming     tar model compound     Ni-based catalyst     carbon resistance    

Shear stress distribution prediction in symmetric compound channels using data mining and machine learning

Zohreh SHEIKH KHOZANI, Khabat KHOSRAVI, Mohammadamin TORABI, Amir MOSAVI, Bahram REZAEI, Timon RABCZUK

《结构与土木工程前沿(英文)》 2020年 第14卷 第5期   页码 1097-1109 doi: 10.1007/s11709-020-0634-3

摘要: Shear stress distribution prediction in open channels is of utmost importance in hydraulic structural engineering as it directly affects the design of stable channels. In this study, at first, a series of experimental tests were conducted to assess the shear stress distribution in prismatic compound channels. The shear stress values around the whole wetted perimeter were measured in the compound channel with different floodplain widths also in different flow depths in subcritical and supercritical conditions. A set of, data mining and machine learning algorithms including Random Forest (RF), M5P, Random Committee, KStar and Additive Regression implemented on attained data to predict the shear stress distribution in the compound channel. Results indicated among these five models; RF method indicated the most precise results with the highest value of 0.9. Finally, the most powerful data mining method which studied in this research compared with two well-known analytical models of Shiono and Knight method (SKM) and Shannon method to acquire the proposed model functioning in predicting the shear stress distribution. The results showed that the RF model has the best prediction performance compared to SKM and Shannon models.

关键词: compound channel     machine learning     SKM model     shear stress distribution     data mining models    

R158Q and G212S, novel pathogenic compound heterozygous variants in of Gitelman syndrome

《医学前沿(英文)》 2022年 第16卷 第6期   页码 932-945 doi: 10.1007/s11684-022-0963-9

摘要: The dysfunction of Na+-Cl cotransporter (NCC) caused by mutations in solute carrier family12, member 3 gene (SLC12A3) primarily causes Gitelman syndrome (GS). In identifying the pathogenicity of R158Q and G212S variants of SLC12A3, we evaluated the pathogenicity by bioinformatic, expression, and localization analysis of two variants from a patient in our cohort. The prediction of mutant protein showed that p.R158Q and p.G212S could alter protein’s three-dimensional structure. Western blot showed a decrease of mutant Ncc. Immunofluorescence of the two mutations revealed a diffuse positive staining below the plasma membrane. Meanwhile, we conducted a compound heterozygous model—Ncc R156Q/G210S mice corresponding to human NCC R158Q/G212S. NccR156Q/G210S mice clearly exhibited typical GS features, including hypokalemia, hypomagnesemia, and increased fractional excretion of K+ and Mg2+ with a normal blood pressure level, which made NccR156Q/G210S mice an optimal mouse model for further study of GS. A dramatic decrease and abnormal localization of the mutant Ncc in distal convoluted tubules contributed to the phenotype. The hydrochlorothiazide test showed a loss of function of mutant Ncc in NccR156Q/G210S mice. These findings indicated that R158Q and G212S variants of SLC12A3 were pathogenic variants of GS.

关键词: Gitelman syndrome     mouse model     compound heterozygous     hypokalemia     Slc12a3    

A compound load simulator based on zero-torsion parallel mechanisms

Jingjun YU, Wei LI, Xu PEI, Shusheng BI, Guanghua ZONG

《机械工程前沿(英文)》 2012年 第7卷 第1期   页码 1-4 doi: 10.1007/s11465-012-0306-7

Engineering practice of mechanical soil aeration for the remediation of volatile organic compound-contaminated

Yan Ma, Xiaoming Du, Yi Shi, Deyi Hou, Binbin Dong, Zhu Xu, Huiying Li, Yunfeng Xie, Jidun Fang, Zheng Li, Yunzhe Cao, Qingbao Gu, Fasheng Li

《环境科学与工程前沿(英文)》 2016年 第10卷 第6期 doi: 10.1007/s11783-016-0870-x

摘要: Engineering practice of mechanical soil aeration in China is reviewed. MSA is a cost-effective technique for VOC-contaminated sites. Limitations of MSA application have been summarized. In recent years, many industrial enterprises located in the urban centers of China have been relocated owing to the rapid increase in urban development. At the sites abandoned by these enterprises, volatile organic compounds have frequently been detected, sometimes at high concentrations, particularly at sites abandoned by chemical manufacturing enterprises. With the redevelopment of sites and changes in land-use type associated with these sites, substantial amounts of contaminated soils now require remediation. Since China is a developing country, soil remediation warrants the usage of techniques that are suitable for addressing the unique challenges faced in this country. Land shortage is a common problem in China; the large numbers of contaminated sites, tight development schedules, and limited financial resources necessitate the development of cost-effective methods for land reclamation. Mechanical soil aeration is a simple, effective, and low-cost soil remediation technique that is particularly suitable for the remediation of large volatile organic compound-contaminated sites. Its effectiveness has been confirmed by conducting laboratory studies, pilot tests, and full-scale projects. This study reviews current engineering practice and developmental trends of mechanical soil aeration and analyzes the advantages and disadvantages of this technology for application in China as an emerging soil remediation market. The findings of this study might aid technology development in China, as well as assist other developing countries in the assessment and implementation of cost-effective hazardous waste site soil remediation programs.

关键词: Soil contamination     Volatile organic compound     Mechanical soil aeration     Engineering practice     China    

绿色化的磷复肥生产集成工艺

冯怡生

《中国工程科学》 1999年 第1卷 第1期   页码 58-62

摘要:

磷复肥生产排放的磷石膏废渣堆存占地,污染环境,已成为亟待解决的难题。利用磷石膏制硫酸与水泥,可消除污染,实现硫资源的良性循环,使经济效益、社会效益和环境效益有机统一,促进了磷复肥工业的可持续发展。

关键词: 磷复肥     磷石膏     硫酸     水泥    

A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication

null

《机械工程前沿(英文)》 2014年 第9卷 第2期   页码 156-167 doi: 10.1007/s11465-014-0297-7

摘要:

A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication (EHL) problems is presented. First, by introducing a special matrix splitting iteration method into the traditional compound direct iterative method, the full matrices for the linear systems of equations are transformed into sparse banded ones with any half-bandwidth; then, an extended Thomas method which can solve banded linear systems with any half-bandwidth is derived to accelerate the computing speed. Through the above two steps, the computational complexity of each iteration is reduced approximately from O(N3/3) to O(β2N), where N is the total number of nodes, and β is the half-bandwidth. Two kinds of numerical results of transient EHL line contact problems under sinusoidal excitation or pure normal approach process are obtained. The results demonstrate that the new algorithm increases computing speed several times more than the traditional compound direct iterative method with the same numerical precision. Also the results show that the new algorithm can get the best computing speed and robustness when the ratio, half-bandwidth to total number of nodes, is about 7.5%–10.0% in moderate load cases.

关键词: elastohydrodynamic lubrication     transient     line contact     matrix splitting iteration method     the Thomas method    

复合式叶片型面测量系统的误差分析与补偿

李兵,陈磊,丁建军,蒋庄德

《中国工程科学》 2013年 第15卷 第1期   页码 39-44

摘要:

针对具有复杂型面的叶片类零件检测中所面临的数字化测量问题,提出了一种复合式的测量原理与方法。分别采用接触式的电感原理和非接触式的激光三角原理测量叶片的叶根基准以及叶身型面,并基于此原理设计研制了叶片型面四坐标测量系统。研究中结合该系统的机械结构特征,对影响其测量精度的各项几何误差进行了系统的分析,并提出了基于激光干涉测量的误差提取与补偿方法。实验结果表明,应用提出的误差分析与补偿方法可有效获取叶片型面四坐标测量系统的几何误差并显著提高其测量精度。

关键词: 叶片型面     复合式测量原理     误差分析     误差补偿     激光干涉测量    

硫酸盐岩与碳酸盐岩复合岩溶发育机理与工程效应研究

卢耀如,张凤娥

《中国工程科学》 2008年 第10卷 第4期   页码 4-10

摘要:

硫酸盐岩和碳酸盐岩常共同分布,以往多是分别研究其岩溶发育。文章主要从自然条件上研究两者复合岩溶发育的机理,探讨了化学岩溶作用过程和生物岩溶作用的机理。复合岩溶中,陷落柱是很重要的一个特征。文章也探索了复合岩溶作用中,有关岩溶地下水的水质情况。

关键词: 硫酸盐岩     碳酸盐岩     复合岩溶     陷落柱     地下水水质    

Effect of compound Sophorae Flavescentis Jiechangrong capsule on expression of NF-κB p65 and STAT6

Heng FAN MD, Jia ZHAO MM, Lin SHEN BM, Qing TANG MD, Zhexin SHOU MM, Li LIANG BM, Yi LIAO BM, Xiaoyan CHEN BM,

《医学前沿(英文)》 2009年 第3卷 第4期   页码 480-484 doi: 10.1007/s11684-009-0083-9

摘要: The effects of compound Sophorae Flavescentis Jiechangrong capsule (CSFJC) on the expression of nuclear factor-κB p65 (NF-κB p65) and signal transducer and activator of transcription 6 (STAT6) in the intestinal mucosa of patients with ulcerative colitis and the possible mechanism were investigated. Eighteen patients with ulcerative colitis were randomly divided into a traditional Chinese medicine (TCM) group ( = 11) treated by CSFJC and a western medicine (WM) group ( = 7) treated by Sulfasalazine tablets. The treatment duration lasted eight weeks. Before and after the treatment, the symptoms and the physical signs were observed, and the routine stool test, the colonoscopy, and pathological examination were performed in the two groups. The expression levels of NF-κBp65 and STAT6 were detected by using immunohistochemistry. The results showed that the total effective rate of the curative effectiveness in TCM and WM groups was 100% and 71.4%, respectively, and the total effective rate of colonic mucosa lesion in TCM and WM groups was 90.9% and 71.4%, respectively, with the differences being significant (all < 0.05). The total effective rate of syndromes of damp-heat blocking according to the TCM in TCM and WM groups was 90.9% and 71.4%, respectively. After the treatment, the expression of NF-κB p65 and STAT6 in the two groups was decreased, and the decrease of NF-κB p65 and STAT6 expression in TCM group was more significant than in WM group ( < 0.05). It was concluded that CSFJC can inhibit the activation and expression of NF-κB p65 and STAT6 in the intestinal mucosa of patients with ulcerative colitis, which is a possible mechanism for CSFJC treating ulcerative colitis.

关键词: colitis     ulcerative     compound Sophorae Flavescentis Jiechangrong capsule     nuclear factor-κ     B p65 (NF-κ     B p65)     signal transducer and activator of transcription 6 (STAT6)    

Deep desulfurization of diesel fuels by catalytic oxidation

YU Guoxian, CHEN Hui, LU Shanxiang, ZHU Zhongnan

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 162-166 doi: 10.1007/s11705-007-0030-8

摘要: Reaction feed was prepared by dissolving dibenzothiophene (DBT), which was selected as a model organosulfur compound in diesel fuels, in -octane. The oxidant was a 30 wt-% aqueous solution of hydrogen peroxide. Catalytic performance of the activated carbons with saturation adsorption of DBT was investigated in the presence of formic acid. In addition, the effects of activated carbon dosage, formic acid concentration, initial concentration of hydrogen peroxide, initial concentration of DBT and reaction temperature on the oxidation of DBT were investigated. Experimental results indicated that performic acid and the hydroxyl radicals produced are coupled to oxidize DBT with a conversion ratio of 100%. Catalytic performance of the combination of activated carbon and formic acid is higher than that of only formic acid. The concentration of formic acid, activated carbon dosage, initial concentration of hydrogen peroxide and reaction temperature affect the oxidative removal of DBT. The higher the initial concentration of DBT in the -octane solution, the more difficult the deep desulfurization by oxidation is.

关键词: organosulfur compound     performic     presence     activated     hydrogen peroxide    

Impact and inhibitory mechanism of phenolic compounds on the formation of toxic Maillard reaction products in food

Jing TENG, Xiaoqian HU, Ningping TAO, Mingfu WANG

《农业科学与工程前沿(英文)》 2018年 第5卷 第3期   页码 321-329 doi: 10.15302/J-FASE-2017182

摘要:

As one of the dominant reactions occurring during thermal treatment of food, the Maillard reaction not only leads to the formation of aroma, browning color and taste compounds, but also contributes to the formation of some unpleasant toxic substances including acrylamide, heterocyclic amines and advanced glycation end products. Polyphenols, one of the most abundant antioxidants in the human diet, are contained in different kinds of foods. In this review, some recent studies on the impact of dietary polyphenols on the formation of acrylamide, heterocyclic amines and advanced glycation end products formed during the Maillard reaction are summarized, including the research work conducted with both chemical model systems and real food model systems; the possible inhibitory mechanisms of different polyphenols are also summarized and discussed in this review. Basically we found that some dietary polyphenols not only scavenge free radicals, but also react with reactive carbonyl species, thus lowering the formation of toxic Maillard reaction products. This review provides a useful theoretical foundation for the application of polyphenols in food safety, and suggests some directions for further study of natural products as inhibitors against the formation of toxic substances in thermally processed food.

关键词: advanced glycation end products     acrylamide     food safety     heterocyclic amine     Maillard reaction     polyphenols    

Role of membrane and compound properties in affecting the rejection of pharmaceuticals by different RO

Yang-ying Zhao, Fan-xin Kong, Zhi Wang, Hong-wei Yang, Xiao-mao Wang, Yuefeng F. Xie, T. David Waite

《环境科学与工程前沿(英文)》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0975-x

摘要: This study was conducted to assess the merits and limitations of various high-pressure membranes, tight nanofiltration (NF) membranes in particular, for the removal of trace organic compounds (TrOCs). The performance of a low-pressure reverse osmosis (LPRO) membrane (ESPA1), a tight NF membrane (NF90) and two loose NF membranes (HL and NF270) was compared for the rejection of 23 different pharmaceuticals (PhACs). Efforts were also devoted to understand the effect of adsorption on the rejection performance of each membrane. Difference in hydrogen bond formation potential (HFP) was taken into consideration. Results showed that NF90 performed similarly to ESPA1 with mean rejection higher than 95%. NF270 outperformed HL in terms of both water permeability and PhAC rejection higher than 90%. Electrostatic effects were more significant in PhAC rejection by loose NF membranes than tight NF and LPRO membranes. The adverse effect of adsorption on rejection by HL and ESPA1 was more substantial than NF270 and NF90, which could not be simply explained by the difference in membrane surface hydrophobicity, selective layer thickness or pore size. The HL membrane had a lower rejection of PhACs of higher hydrophobicity (log D>0) and higher HFP (>0.02). Nevertheless, the effects of PhAC hydrophobicity and HFP on rejection by ESPA1 could not be discerned. Poor rejection of certain PhACs could generally be explained by aspects of steric hindrance, electrostatic interactions and adsorption. High-pressure membranes like NF90 and NF270 have a high promise in TrOC removal from contaminated water.

关键词: Trace organic compounds (TrOCs)     Nanofiltration (NF)     Adsorption     Membrane properties     Water treatment    

标题 作者 时间 类型 操作

N-Positive ion activated rapid addition and mitochondrial targeting ratiometric fluorescent probes for in vivo cell H2S imaging

Yan Shi, Fangjun Huo, Yongkang Yue, Caixia Yin

期刊论文

Extractive desulfurization of model fuels with a nitrogen-containing heterocyclic ionic liquid

期刊论文

Steam reforming of toluene as a tar model compound with modified nickel-based catalyst

Omeralfaroug KHALIFA, Mingxin XU, Rongjun ZHANG, Tahir IQBAL, Mingfeng LI, Qiang LU

期刊论文

Shear stress distribution prediction in symmetric compound channels using data mining and machine learning

Zohreh SHEIKH KHOZANI, Khabat KHOSRAVI, Mohammadamin TORABI, Amir MOSAVI, Bahram REZAEI, Timon RABCZUK

期刊论文

R158Q and G212S, novel pathogenic compound heterozygous variants in of Gitelman syndrome

期刊论文

A compound load simulator based on zero-torsion parallel mechanisms

Jingjun YU, Wei LI, Xu PEI, Shusheng BI, Guanghua ZONG

期刊论文

Engineering practice of mechanical soil aeration for the remediation of volatile organic compound-contaminated

Yan Ma, Xiaoming Du, Yi Shi, Deyi Hou, Binbin Dong, Zhu Xu, Huiying Li, Yunfeng Xie, Jidun Fang, Zheng Li, Yunzhe Cao, Qingbao Gu, Fasheng Li

期刊论文

绿色化的磷复肥生产集成工艺

冯怡生

期刊论文

A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication

null

期刊论文

复合式叶片型面测量系统的误差分析与补偿

李兵,陈磊,丁建军,蒋庄德

期刊论文

硫酸盐岩与碳酸盐岩复合岩溶发育机理与工程效应研究

卢耀如,张凤娥

期刊论文

Effect of compound Sophorae Flavescentis Jiechangrong capsule on expression of NF-κB p65 and STAT6

Heng FAN MD, Jia ZHAO MM, Lin SHEN BM, Qing TANG MD, Zhexin SHOU MM, Li LIANG BM, Yi LIAO BM, Xiaoyan CHEN BM,

期刊论文

Deep desulfurization of diesel fuels by catalytic oxidation

YU Guoxian, CHEN Hui, LU Shanxiang, ZHU Zhongnan

期刊论文

Impact and inhibitory mechanism of phenolic compounds on the formation of toxic Maillard reaction products in food

Jing TENG, Xiaoqian HU, Ningping TAO, Mingfu WANG

期刊论文

Role of membrane and compound properties in affecting the rejection of pharmaceuticals by different RO

Yang-ying Zhao, Fan-xin Kong, Zhi Wang, Hong-wei Yang, Xiao-mao Wang, Yuefeng F. Xie, T. David Waite

期刊论文