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Real atom economy and its application for evaluation the green degree of a process

Weihan WANG, Jing Lü, Li ZHANG, Zhenhua LI

《化学科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 349-354 doi: 10.1007/s11705-010-1030-7

摘要： Green chemistry has attracted more attention in the past century. Among the 12 principles of green chemistry, only atom economy and E factor can be expressed quantitatively to depict the impact of a chemical process to environment. Atom economy was thought better than the traditional yield for evaluating the atom efficiency of raw materials. But it is not enough to reflect the conversion degree of raw material. In this paper, we proposed the concept of real atom economy (RAE) as a metric. RAE could combine the above two factors together to better express the green degree of a process. We further suggested an equation to correlate E factor with RAE. The concept of RAE is proved to be helpful for estimating an environmentally benign process.

关键词： green chemistry     real atom economy     E factor     atom economy     yield    

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Effects of hypoxia inducible factor-1alpha siRNA on the invasion of human Hela cells and expression of

Bin YANG MS , Xianglin YUAN , Yanmei ZOU , Qingsong XI , Guoxian LONG , Qiang FU , Guangyuan HU MM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 303-308 doi: 10.1007/s11684-009-0060-3

摘要： The effects of hypoxia on the invasion and the related protein expression of Hela cells and the role of hypoxia inducible factor-1α (HIF-1α) were investigated. The Hela cells were divided into three groups, namely, H (non-transfected Hela cells), H (pGenesil-1 empty plasmid-transfected Hela cells), and H (HIF-1α-shRNA plasmid-transfected Hela cells), and were cultured under hypoxia (1% O) and normoxia for 48h. The expression of HIF-1α, E-cadherin, β-catenin, and actin was detected using Western blot. The scratch test and the invasion assay were applied to examine the invasion in each group. The expression of HIF-1α, E-cadherin, and β-catenin in tumor grafts was assayed immunohistochemically. Western blot results revealed that the bands of HIF-1α, E-cadherin, β-catenin, and actin proteins were detected in the H and H groups under hypoxia for 48h. The expression of E-cadherin, β-catenin, and actin was detected in the H group under hypoxia for 48h, and normoxia. In the H, H, and H groups under normoxia, and the H group under hypoxia for 48h, no expression of HIF-1α was detectable. The scratch test showed that the invasive ability in the H group was significantly alleviated. Immunohistochemically, it was found that there was a significant difference in the expression of HIF-1α, E-cadherin, and β-catenin between the H and H groups (<0.05), but the difference was not significant between the H and H groups. It was concluded that the effects of hypoxia on the invasion of human cervical cancer Hela cells and the expression of related proteins (E-cadherin, β-catenin, and actin) depend on HIF-1α.

关键词： hypoxia     actin     β     -catenin     E-cadherin     invasion    

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Quantitatively assessing the pre-grouting effect on the stability of tunnels excavated in fault

Xiao YAN, Zizheng SUN, Shucai LI, Rentai LIU, Qingsong ZHANG, Yiming ZHANG

《结构与土木工程前沿（英文）》 2019年 第13卷 第6期   页码 1393-1404 doi: 10.1007/s11709-019-0563-1

摘要： Pre-grouting is a popular ground treatment strategy utilized to enhance the strength and stability of strata during the excavation of a tunnel through a fault zone. Two important questions need to be answered during such an excavation. First, how should the grouting size be determined? Second, when should excavation begin after grouting? These two questions are conventionally addressed through empirical experience and standard criteria because a reliable quantitative approach, which would be preferable, has not yet been developed. To address these questions, we apply a recently proposed numerical approach known as discontinuity layout optimization, an efficient node-based upper bound limit analysis method. A case study is provided utilizing a tunnel located in a stratum characterized by complicated geological conditions, including soft soil and a fault zone. The factor of safety is used to quantitatively assess the stability of the tunnel section. The influences of the grouted zone thickness and the time-dependent material properties of the grouted zone on the stability of the tunnel section are evaluated, thereby assisting designers by quantitatively assessing the effects of pre-grouting.

关键词： pre-grouting     stability analysis     factor of safety     discontinuity layout optimization    

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Sustainability of metal recovery from E-waste

Biswajit Debnath, Ranjana Chowdhury, Sadhan Kumar Ghosh

《环境科学与工程前沿（英文）》 2018年 第12卷 第6期 doi: 10.1007/s11783-018-1044-9

摘要：

Metal recovery techniques from electronic waste reported in literature.

Metal recovery processes followed in Industries from electronic waste.

Sustainability analysis of metal recovery processes from electronic waste.

关键词： E-waste     Metal recovery     Metal Recovery from E-waste (MREW)     Sustainability    

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Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 376-380 doi: 10.1007/s11684-012-0228-0

摘要：

The forkhead transcription factors FOXO and FOXM1 have pivotal roles in tumorigenesis and in mediating chemotherapy sensitivity and resistance. Recent research shows that the forkhead transcription factor FOXM1 is a direct transcriptional target repressed by the forkhead protein FOXO3a, a vital downstream effector of the PI3K-AKT-FOXO signaling pathway. Intriguingly, FOXM1 and FOXO3a also compete for binding to the same gene targets, which have a role in chemotherapeutic drug action and sensitivity. An understanding of the role and regulation of the FOXO-FOXM1 axis will impact directly on our knowledge of chemotherapeutic drug action and resistance in patients, and provide new insights into the design of novel therapeutic strategy and reliable biomarkers for prediction of drug sensitivity.

关键词： FOXO3a     FOXM1     transcription factor     cancer     drug resistance     tumorigenesis    

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LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

《结构与土木工程前沿（英文）》 2022年 第16卷 第7期   页码 871-881 doi: 10.1007/s11709-022-0863-8

摘要： The failure criteria of practical soil mass are very complex, and have significant influence on the safety factor of slope stability. The Coulomb strength criterion and the power-law failure criterion are classically simplified. Each one has limited applicability owing to the noticeable difference between calculated predictions and actual results in some cases. In the work reported here, an analysis method based on the least square support vector machine (LSSVM), a machine learning model, is purposefully provided to establish a complex nonlinear failure criterion via iteration computation based on strength test data of the soil, which is of more extensive applicability to many problems of slope stability. In particular, three evaluation indexes including coefficient of determination, mean absolute percentage error, and mean square error indicate that fitting precision of the machine learning-based failure criterion is better than those of the linear Coulomb criterion and nonlinear power-law criterion. Based on the proposed LSSVM approach to determine the failure criterion, the limit equilibrium method can be used to calculate the safety factor of three-dimensional slope stability. Analysis of results of the safety factor of two three-dimensional homogeneous slopes shows that the maximum relative errors between the proposed approach and the linear failure criterion-based method and the power-law failure criterion-based method are about 12% and 7%, respectively.

关键词： slope stability     safety factor     failure criterion     least square support vector machine    

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lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

《医学前沿（英文）》 2023年 第17卷 第2期   页码 317-329 doi: 10.1007/s11684-022-0931-4

摘要： Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

关键词： lncR-GAS5     miR-193-5p     splicing factor SRSF10     autophagy     atherogenesis    

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Molecular dynamics modeling of a single diamond abrasive grain in grinding

SAVVOPOULOS,Nikolaos E. KARKALOS,Dimitrios E. MANOLAKOS

《机械工程前沿（英文）》 2015年 第10卷 第2期   页码 168-175 doi: 10.1007/s11465-015-0337-y

摘要：

In this paper the nano-metric simulation of grinding of copper with diamond abrasive grains, using the molecular dynamics (MD) method, is considered. An MD model of nano-scale grinding, where a single diamond abrasive grain performs cutting of a copper workpiece, is presented. The Morse potential function is used to simulate the interactions between the atoms involved in the procedure. In the proposed model, the abrasive grain follows a curved path with decreasing depth of cut within the workpiece to simulate the actual material removal process. Three different initial depths of cut, namely 4 ?, 8 ? and 12 ?, are tested, and the influence of the depth of cut on chip formation, cutting forces and workpiece temperatures are thoroughly investigated. The simulation results indicate that with the increase of the initial depth of cut, average cutting forces also increase and therefore the temperatures on the machined surface and within the workpiece increase as well. Furthermore, the effects of the different values of the simulation variables on the chip formation mechanism are studied and discussed. With the appropriate modifications, the proposed model can be used for the simulation of various nano-machining processes and operations, in which continuum mechanics cannot be applied or experimental techniques are subjected to limitations.

关键词： molecular dynamics     abrasive process     chip formation     cutting force     temperature    

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risks of heavy metals, polybrominated diphenyl ethers, and polychlorinated dibenzo-dioxins/furans at e-waste

《环境科学与工程前沿（英文）》 2023年 第17卷 第7期 doi: 10.1007/s11783-023-1679-z

摘要：

● Heavy metals and organic toxins may persist in legacy sites for a long time.

关键词： E-waste     Human health risk     Organ risk     Heavy metal toxicity     PBDE     PCDD/F    

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The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 1015-1024 doi: 10.1007/s11783-014-0670-0

摘要： The Ecological Footprint (EF), a physical indicator to measure the extent of humanity’s use of natural resources, has gained much attention since it was first used by Wackernagel and Rees in 1996. In order to appraise land area types with different levels of productivity, they introduced the concept of an equivalence factor. This relates to the average primary biomass productivities of different types of land (i.e. arable land, pasture, forest, water/fishery, built-up land and fossil energy land) to the regional average primary biomass productivity of all land types in a given year. Hence, the equivalence factor is an important parameter in the EF model and it directly affects the reliability of all results. Thus, this article calculates equivalence factors on the national and provincial levels in China based on Net Primary Production (NPP) from MODIS 1 km data in 2008. Firstly, based on the Light Utility Efficiency and CASA model, the NPP of different biologically productive lands of China and of different provinces was calculated. Secondly, China’s equivalence factor for 6 land area types was calculated based on NPP: arable land and built-up land has an equivalence factor of 1.71, forest and fossil energy land has a factor of 1.41, pasture has a factor of 0.44 and water/fishery 0.35; Finally, the equivalence factor of 6 land area types in different provinces was also calculated. The NPP of each ecosystem type varies along with the equivalence factor in different provinces. However, the ranking of the equivalence factors in different provinces remain the same, with that of arable land being the largest, and the water/fishery being the smallest.

关键词： ecological footprint     equivalence factor     net primary production     biological capacity     land types    

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A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 877-894 doi: 10.1007/s11709-021-0756-2

摘要： Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.

关键词： bridges     multi-lane factor     traffic load     lane load disparity     multi-truck presence     weigh-in-motion data    

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Policy options for Agriculture Green Development by farmers in China

Laurence E. D. SMITH

《农业科学与工程前沿（英文）》 2020年 第7卷 第1期   页码 90-97 doi: 10.15302/J-FASE-2019290

摘要：

Farmers are the key agents who manage land and water. Agriculture Green Development (AGD) requires a transformation in farming from high resource consumption and environmental cost to sustainable intensification with high productivity, high resource use efficiency and low environmental risk. This paper analyzes the public policy challenge of AGD and makes the case for a location-sensitive policy mix made up of regulation, advice provision, voluntarism and targeted incentives. The public agricultural extension service in China is a key resource, but one that requires reorientation and reform with the aim of better balancing high farm productivity with environmental protection.

关键词： agriculture     environment     development     incentives     policy     regulation    

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数字采矿技术在岩爆风险评估中的应用

Sousa Luis Ribeiro e,Miranda Tiago,Sousa Rita Leal e,Tinoco Joaquim

《工程（英文）》 2017年 第3卷 第4期   页码 552-558 doi: 10.1016/J.ENG.2017.04.002

摘要：

目前在世界范围内的很多地下矿山，岩爆已经成为一个与矿山采矿生产密切相关的重要现象。深入理解这类现象，不仅有助于岩爆管理，而且还有可能节约采矿成本，减少人身伤亡事故。其中，实验室实验是深入研究岩爆机理的一个重要途径。在本文作者前期的研究中，已经建立了实验室岩爆实验数据库。与此同时，借助于数字采矿技术，也建立了岩爆最大应力和岩爆风险指数的预测模型。为实现基于矿山地质条件和矿山井巷建筑结构特性对岩爆类型即岩爆强度等级的准确预测，本文的重点是，基于对岩爆实例的分析来建立岩爆影响矩阵，明确岩爆现象的诱发因子，并厘清这些影响因子之间的相互关系。运用人工神经网络（ANN）和初始贝叶斯分类器等数字矿山技术，对矿山岩爆数据库进行了更深入的研究。最后给出了研究得出的各项结论。

关键词： 岩爆     数字采矿     贝叶斯网络     原位数据库    

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Investigation of electrochemical degradation and application of e-paper dyes in organic solvents

Luhai LI, Ming WANG, Yi FANG, Shunan QIAO

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 182-185 doi: 10.1007/s11705-009-0062-3

摘要： To avoid environmental pollution due to organic dye solutions, the electrophoresis and degradation of dye in organic solvents such as alcohol were investigated. Many dyes were tested in the Indium tin oxide (ITO) electrode driving cell, and about 15 dyes moved under voltage driving. Both the curves of ultraviolet-visible (UV-Vis) and infrared (IR) spectra of the electrophoresis samples showed that the metal complexes Red 04 and Acid Black 1 were degradable in alcohol solution by electrochemical reaction. The cyclic volt-ampere curves of the samples from the electrochemical working station proved that electrochemical reactions took place. Based on the analysis of UV-Vis and IR spectra, the electrochemical degradation products of azo and metal complex azo dyes at lower voltage driving (1-5 V) in organic solvents are oxidized azobenzene, not hydrazine, which was found in the electrochemical degradation of dye water solutions. When the ITO electrode is modified by a polyimide (PI) film to a thickness less than 4 μm, the electrochemical degradation of the dye in alcohol solution will not appear in the cyclic volt-ampere curves. A dye electrophoresis in organic solution flexible prototype e-paper display was formed and the display picture is shown.

关键词： electrochemical degradation     electrophoresis     e-paper     oxidized azobenzene group    

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Numerical investigation of the influence of kinetics and shape factor on barium sulfate precipitation

Zheng WANG, Zai-Sha MAO, Chao YANG, Qinghua ZHANG, Jingcai CHENG

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 272-281 doi: 10.1007/s11705-009-0023-x

摘要： The effect of kinetics and shape factor on barium sulfate precipitation in a continuous stirred tank has been investigated numerically through solving the standard momentum and mass transport equations in combination with the moment equations for crystal population balance. The numerical method was validated with the literature data. The simulated results include the distribution of the local supersaturation ratio in the reactor, the mean crystal size, and the coefficient of variation. The simulation results show that the value of shape factor used in the model affected greatly the mean crystal size and the moments of the crystal size distribution. The influence of the kinetic expressions on the simulation is also analyzed. It is important to investigate the relationship of the shape factor with the precipitator type and other operation conditions to obtain reliable simulation results and suitable kinetic equations of crystal nucleation and growth rates.

关键词： stirred tank     numerical simulation     precipitation     shape factor     crystal kinetics    

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标题 作者 时间 类型 操作

Real atom economy and its application for evaluation the green degree of a process

Weihan WANG, Jing Lü, Li ZHANG, Zhenhua LI

期刊论文

Effects of hypoxia inducible factor-1alpha siRNA on the invasion of human Hela cells and expression of

Bin YANG MS , Xianglin YUAN , Yanmei ZOU , Qingsong XI , Guoxian LONG , Qiang FU , Guangyuan HU MM ,

期刊论文

Quantitatively assessing the pre-grouting effect on the stability of tunnels excavated in fault

Xiao YAN, Zizheng SUN, Shucai LI, Rentai LIU, Qingsong ZHANG, Yiming ZHANG

期刊论文

Sustainability of metal recovery from E-waste

Biswajit Debnath, Ranjana Chowdhury, Sadhan Kumar Ghosh

期刊论文

Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

期刊论文

LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

期刊论文

lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

期刊论文

Molecular dynamics modeling of a single diamond abrasive grain in grinding

SAVVOPOULOS,Nikolaos E. KARKALOS,Dimitrios E. MANOLAKOS

期刊论文

risks of heavy metals, polybrominated diphenyl ethers, and polychlorinated dibenzo-dioxins/furans at e-waste

期刊论文

The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

期刊论文

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

期刊论文

Policy options for Agriculture Green Development by farmers in China

Laurence E. D. SMITH

期刊论文

数字采矿技术在岩爆风险评估中的应用

Sousa Luis Ribeiro e,Miranda Tiago,Sousa Rita Leal e,Tinoco Joaquim

期刊论文

Investigation of electrochemical degradation and application of e-paper dyes in organic solvents

Luhai LI, Ming WANG, Yi FANG, Shunan QIAO

期刊论文

Numerical investigation of the influence of kinetics and shape factor on barium sulfate precipitation

Zheng WANG, Zai-Sha MAO, Chao YANG, Qinghua ZHANG, Jingcai CHENG

期刊论文