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An assessment of China-Japan-Korea Free Trade Agreement’s economic and environmental impacts on China

Zhaoyang LIU, Xianqiang MAO, Wei TANG, Tao HU, Peng SONG

《环境科学与工程前沿（英文）》 2012年 第6卷 第6期   页码 849-859 doi: 10.1007/s11783-012-0432-9

摘要： Recently, China, Japan, and the Republic of Korea (Korea) are conducting a government-commissioned feasibility study on the Free Trade Agreement among the three countries (CJKFTA) to form a regional free trade zone in East Asia. Considering that freer trade can cause unexpected impact on domestic environment, there is a need to evaluate the environmental impact of such a trade policy. This move should be made to help negotiators understand and pay more attention to environmental issues during CJKFTA negotiations, and to help lobby with the government to carry out appropriate policy instruments for adaptation or mitigation. Following the Chain Reaction Assessment Method that integrates and links the elements of trade, production, and environment, the present research aims to quantitatively assess CJKFTA’s possible impact on China’s environment. This is done by estimating the variations of China’s major conventional pollutants and greenhouse gases (GHGs) emission in two policy scenarios to represent CJKFTA’s scale and composition effects on China’s environment. Estimating the variations is based on a static Computable General Equilibrium model, working with Global Trade Analysis Project (GTAP) 7 database and China’s energy-environment statistics. Based on these assessments, CJKFTA is predicted to lead to notable environmental impact, including increased emissions of agricultural total nitrogen, agricultural total phosphorus, chemical oxygen demand, and GHGs. On the other hand, decreased emissions of industrial SO and dust are also expected to happen. Suitable policies need to be made to combat negative effects and amplify positive ones, while aiming at a more sustainable regional freer trade system.

关键词： Free Trade Agreement     Strategic Environmental Assessment     Chain Reaction Assessment Method     Computable General Equilibrium model     Global Trade Analysis Project    

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Continuous reaction performances of benzene alkylation with long chain olefins catalyzed by ionic liquid

QIAO Congzhen, LI Chengyue

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 69-73 doi: 10.1007/s11705-008-0014-3

摘要： Based on a compulsive mixing-reacting-separating-recycling small experimental setup,the continuous reaction performances of benzene alkylation with long chain olefins catalyzed by [BMIM]Cl-AlCl ionic liquid were investigated. Three different situations including normal continuous operation mode (reagent materials), sidetrack feeding from different axial positions along the static mixing reactor (reagent materials) and normal continuous alkylation using industrial paraffin and olefins materials were examined. Even under the relatively hypecritical reaction conditions, the single pass conversion of pure 1-dodecene could reach to nearly 100.0%, and the selectivity of 2-phenyl isomer was higher than 37.7%. Although the positions along the reactor for sidetrack feeding were different, the 100.0% single pass conversion of 1-dodecene was also attained before the outlet of the reactor. The refined industrial olefins as raw material could meet with the requirements of continuous alkylation. The influences of impurities such as di-olefins and non-benzene aromatics on the catalytic activity and stability should be studied further.

关键词： stability     different     hypecritical     compulsive mixing-reacting-separating-recycling     non-benzene    

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A systemic review of hydrogen supply chain in energy transition

《能源前沿（英文）》 2023年 第17卷 第1期   页码 102-122 doi: 10.1007/s11708-023-0861-0

摘要： Targeting the net-zero emission (NZE) by 2050, the hydrogen industry is drastically developing in recent years. However, the technologies of hydrogen upstream production, midstream transportation and storage, and downstream utilization are facing obstacles. In this paper, the development of hydrogen industry from the production, transportation and storage, and sustainable economic development perspectives were reviewed. The current challenges and future outlooks were summarized consequently. In the upstream, blue hydrogen is dominating the current hydrogen supply, and an implementation of carbon capture and sequestration (CCS) can raise its cost by 30%. To achieve an economic feasibility, green hydrogen needs to reduce its cost by 75% to approximately 2 /kg at the large scale. The research progress in the midterm sector is still in a preliminary stage, where experimental and theoretical investigations need to be conducted in addressing the impact of embrittlement, contamination, and flammability so that they could provide a solid support for material selection and large-scale feasibility studies. In the downstream utilization, blue hydrogen will be used in producing value-added chemicals in the short-term. Over the long-term, green hydrogen will dominate the market owing to its high energy intensity and zero carbon intensity which provides a promising option for energy storage. Technologies in the hydrogen industry require a comprehensive understanding of their economic and environmental benefits over the whole life cycle in supporting operators and policymakers.

关键词： hydrogen production     hydrogen transportation and storage     hydrogen economy     carbon capture and sequestration (CCS)     technology assessment    

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Rosin side chain type catalyst-free vitrimers with high cross-link density, mechanical strength, and

《化学科学与工程前沿（英文）》 2023年 第17卷 第9期   页码 1267-1279 doi: 10.1007/s11705-022-2291-7

摘要： The emergence of vitrimer, a new class of polymer materials can address the problem of recyclability, reprocess ability and recyclability of thermosetting plastics. Rosin, a natural product, is an ideal raw material for the preparation of polymers in a more sustainable way. Nevertheless, due to the huge steric hindrance caused by the hydrogenated phenanthrene ring structure, the cross-link density of materials is frequently lowered. In this study, hydrogenated rosin was adopted for preparing hydrogenated rosin side-chain type diacids, which were reacted with mixed epoxy to obtain rosin side-chain type vitrimers. It was completely characterized by differential scanning calorimetry test, thermogravimetric analysis, shape memory test and self-healing test. The prepared vitrimers exhibited good self-healing properties, excellent heat resistance (Td = 352 °C) as well as high mechanical properties (tensile strength of 46.75 MPa). The tricyclic diterpene structure of rosin was introduced into the side chain in order to avoid the reduction of cross-link density resulting from the huge steric hindrance of the rigid tricyclic hydrophenylene skeleton. Vitrimers can undergo dynamic transesterification reaction without external catalysts due to the autocatalytic effect of tertiary amines from epoxy. Moreover, our work expanded the application field of rosin, increased the added value of rosin, and provided a novel method for preparing rosin-based vitrimers with ideal properties.

关键词： vitrimers     rosin     catalyst-free     high mechanical properties     dynamic transesterification reaction    

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Lignin-based polymer with high phenolic hydroxyl group content prepared by the alkyl chain bridging method

《化学科学与工程前沿（英文）》 2023年 第17卷 第8期   页码 1075-1084 doi: 10.1007/s11705-022-2272-x

摘要： Inspired by the importance of the phenolic group to the electron transporting property of hole transport materials, phenolic hydroxyl groups were introduced in lignosulfonate (LS) via the alkyl chain bridging method to prepare phenolated-lignosulfonate (PLS). The results showed that the phenolic group was boosted from 0.81 mmol∙g–1 of LS to 1.19 mmol∙g–1 of PLS. The electrochemical property results showed two oxidation peaks in the cyclic voltammogram (CV) curve of PLS, and the oxidation potential of the PLS-modified electrode decreased by 0.5 eV compared with that of LS. This result indicates that PLS is more easily oxidized than LS. Based on the excellent electron transporting property of PLS, PLS was applied as a dopant in poly(3,4-ethylenedioxythiophene) (PEDOT, called PEDOT:PLSs). PLS showed excellent dispersion properties for PEDOT. Moreover, the transmittance measurement results showed that the transmittance of PEDOT:PLSs exceeded 85% in the range of 300–800 nm. The CV results showed that the energy levels of PEDOT:PLSs could be flexibly adjusted by PLS amounts. The results indicate that the phenolic hydroxyl group of lignin can be easily boosted by the alkyl chain bridging method, and phenolated lignin-based polymers may have promising potential as dopants of PEDOT to produce hole transporting materials for different organic photovoltaic devices.

关键词： lignosulfonate     phenolic group     PEDOT:PLS     hole extract layer     energy level    

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A case study on sample average approximation method for stochastic supply chain network design problem

Yuan WANG, Ruyan SHOU, Loo Hay LEE, Ek Peng CHEW

《工程管理前沿（英文）》 2017年 第4卷 第3期   页码 338-347 doi: 10.15302/J-FEM-2017032

摘要： This study aims to solve a typical long-term strategic decision problem on supply chain network design with consideration to uncertain demands. Existing methods for these problems are either deterministic or limited in scale. We analyze the impact of uncertainty on demand based on actual large data from industrial companies. Deterministic equivalent model with nonanticipativity constraints, branch-and-fix coordination, sample average approximation (SAA) with Bayesian bootstrap, and Latin hypercube sampling were adopted to analyze stochastic demands. A computational study of supply chain network with front-ends in Europe and back-ends in Asia is presented to highlight the importance of stochastic factors in these problems and the efficiency of our proposed solution approach.

关键词： supply chain network     stochastic demand     sampling average approximation     Bayesian bootstrap     Latin hypercube sampling    

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Using pyrosequencing and quantitative PCR to analyze microbial communities

Husen ZHANG

《环境科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 21-27 doi: 10.1007/s11783-011-0303-9

摘要： New high-throughput technologies continue to emerge for studying complex microbial communities. In particular, massively parallel pyrosequencing enables very high numbers of sequences, providing a more complete view of community structures and a more accurate inference of the functions than has been possible just a few years ago. In parallel, quantitative real-time polymerase chain reaction (QPCR) allows quantitative monitoring of specific community members over time, space, or different environmental conditions. In this review, the principles of these two methods and their complementary applications in studying microbial ecology in bioenvironmental systems are discussed. The parallel sequencing of amplicon libraries and using barcodes to differentiate multiple samples in a pyrosequencing run are explained. The best procedures and chemistries for QPCR amplifications are also described and advantages of applying automation to increase accuracy are addressed. Three examples in which pyrosequencing and QPCR were used together to define and quantify members of microbial communities are provided: in the human large intestine, in a methanogenic digester whose sludge was made more bioavailable by a high-voltage pretreatment, and on the biofilm anode of a microbial electrolytic cell. The key findings in these systems and how both methods were used in concert to achieve those findings are highlighted.

关键词： polymerase chain reaction (PCR)     microbial communities     pyrosequencing     gut     microbial fuel cell     sludge    

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An integrated assessment method of urban drainage system: A case study in Shenzhen City, China

DONG Xin, ZENG Siyu, CHEN Jining, ZHAO Dongquan

《环境科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 150-156 doi: 10.1007/s11783-008-0014-z

摘要： In recent years, the urban drainage system in China is facing the dual pressure of renovation and construction. This requires that the integrated assessment for the planning and operation of the urban drainage system is obligatory. To evaluate the urban drainage system, an integrated assessment methodology based on the analytic hierarchy process (AHP), integrated simulation, and fuzzy assessment is established. This method is a multi-criteria decision adding app roach to the assessment of the urban drainage system comprehensively. Through the integration of the Storm Water Management Model (SWMM), a simple wastewater treatment plant model, and a surface water quality model, an integrated modelling system for the urban drainage system is developed and applied as a key tool for assessment. Using the established method, a case study in Shenzhen City has been implemented to evaluate and compare two urban drainage system reno vation plans, the distributed plan and the centralized plan. Because of the particularity of this case study, the established method is not applied entirely. Considering the water environ mental impact, ecological impact, technological feasibility, and economic cost, the integrated performance of the distri buted plan is better. As shown in this case study, the proposed method is found to be both effective and practical.

关键词： integrated assessment     hierarchy process     centralized     technological feasibility     planning    

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单自由度平面闭链机构构型方法的研究

张美麟,张晔,杨治义

《中国工程科学》 2002年 第4卷 第6期   页码 5-8

摘要：

提出了一种关于自由度平面闭链机构的构型方法，即“平面图形构造方法”。利用这种方法进行机构结构综合的主要过程是：先根据机械功能确定运动链的组成成分；再按这些成分构造平面图；最后在平面图上进行机构的构型和变异，并将其中结构最优者转换为机构简图。

关键词： 机构     运动链     平面图    

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API-based assessment on urban air environment bearing capability in China

Jinnan WANG,Jing ZHANG,Hongqiang JIANG,Yaling LU

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 1049-1055 doi: 10.1007/s11783-014-0662-0

摘要： Given the complexity and time-consuming of the conventional environmental capacity based assessment on air environment carrying capacity; a new method for assessing urban air environment carrying capacity based on air pollution index (API) is presented. By using this new method, the air environmental bearing capability of 333 cities at the prefecture level and above is assessed. The results show that of the 333 cities 9.6% is of high bearing capability, 34.5% relatively high bearing capability, 52.6% medium bearing capability, 2.7% low capability, and 0.6% is of weak bearing capability; in terms of regional distribution, the western region is of relatively high air environment bearing capability, followed by north-eastern and eastern regions, and the ambient air quality in the middle region is quite poor; among the 12 urban agglomerations in key regions, Pearl River delta, west side of Taiwan Strait and Chengdu-Chongqing agglomerations are of relatively high carrying capacity while other agglomerations are of medium bearing capability. The assessment results imply that the existing air quality standard (GB3095-1996) is quite unsound.

关键词： air pollution index (API)     air environment bearing capability     key city     assessment method    

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Synthesis and characterization of magnesium hydroxide by batch reaction crystallization

Xingfu SONG, Shuying SUN, Dengke ZHANG, Jin WANG, Jianguo YU

《化学科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 416-421 doi: 10.1007/s11705-011-1125-9

摘要： Magnesium hydroxide with high purity and uniform particle size distribution was synthesized by the direct precipitation method using MgCl and NaOH as reactive materials and NaCl as additive to improve the crystallization behavior of the product. The particle size distribution, crystal phase, morphology, and surface area of magnesium hydroxide were characterized by Malvern laser particle size analyzer, X-ray diffraction (XRD), scanning electron microscope (SEM) and Branauer-Emmett-Teller (BET) method, respectively. The purity of products was analyzed by the chemical method. The effects of synthesis conditions on the particle size distribution and water content (filtration cake) of magnesium hydroxide were investigated. The results indicated that feeding mode and rate, and reaction temperature had important effects on water content and the particle size distribution of the product, and sodium chloride improved the crystallization behavior of magnesium hydroxide. The ball-like magnesium hydroxides with the particle size distribution of 6.0–30.0 μm and purity higher than 99.0% were obtained. This simple and mild synthesis method was promising to be scaled up for the industrial production of magnesium hydroxide.

关键词： magnesium hydroxide     direct precipitation method     industrial crystallization     particle size distribution    

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Liquefaction assessment using microtremor measurement, conventional method and artificial neural network

Sadegh REZAEI,Asskar Janalizadeh CHOOBBASTI

《结构与土木工程前沿（英文）》 2014年 第8卷 第3期   页码 292-307 doi: 10.1007/s11709-014-0256-8

摘要： Recent researchers have discovered microtremor applications for evaluating the liquefaction potential. Microtremor measurement is a fast, applicable and cost-effective method with extensive applications. In the present research the liquefaction potential has been reviewed by utilization of microtremor measurement results in Babol city. For this purpose microtremor measurements were performed at 60 measurement stations and the data were analyzed by suing Nakmaura’s method. By using the fundamental frequency and amplification factor, the value of vulnerability index ( ) was calculated and the liquefaction potential has been evaluated. To control the accuracy of this method, its output has been compared with the results of Seed and Idriss [ ] method in 30 excavated boreholes within the study area. Also, the results obtained by the artificial neural network (ANN) were compared with microtremor measurement. Regarding the results of these three methods, it was concluded that the threshold value of liquefaction potential is . On the basis of the analysis performed in this research it is concluded that microtremors have the capability of assessing the liquefaction potential with desirable accuracy.

关键词： liquefaction     microtremor     vulnerability index     artificial neural networks (ANN)     microzonation    

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一种通过检测特定粪便微生物群来评估人体肠道微生物稳态的方法 Article

Zhongwen Wu, Xiaxia Pan, Yin Yuan, Pengcheng Lou, Lorina Gordejeva, Shuo Ni, Xiaofei Zhu, Bowen Liu, Lingyun Wu, Lanjuan Li, Bo Li

《工程（英文）》 2023年 第29卷 第10期   页码 110-119 doi: 10.1016/j.eng.2023.03.007

摘要：

Research on microecology has been carried out with broad perspectives in recent decades, which has enabled a better understanding of the gut microbiota and its roles in human health and disease. It is of great significance to routinely acquire the status of the human gut microbiota; however, there is no method to evaluate the gut microbiome through small amounts of fecal microbes. In this study, we found ten predominant groups of gut bacteria that characterized the whole microbiome in the human gut from a largesample Chinese cohort, constructed a real-time quantitative polymerase chain reaction (qPCR) method and developed a set of analytical approaches to detect these ten groups of predominant gut bacterial species with great maneuverability, efficiency, and quantitative features. Reference ranges for the ten predominant gut bacterial groups were established, and we found that the concentration and pairwise ratios of the ten predominant gut bacterial groups varied with age, indicating gut microbial dysbiosis. By comparing the detection results of liver cirrhosis (LC) patients with those of healthy control subjects, differences were then analyzed, and a classification model for the two groups was built by machine learning. Among the six established classification models, the model established by using the random forest algorithm achieved the highest area under the curve (AUC) value and sensitivity for predicting LC. This research enables easy, rapid, stable, and reliable testing and evaluation of the balance of the gut microbiota in the human body, which may contribute to clinical work.

关键词： Gut microbiota     Machine learning     Microbial dysbiosis     Quantitative polymerase chain reaction     Chinese cohort    

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生鲜农产品冷链储运技术装备发展研究

杨天阳,田长青,刘树森

《中国工程科学》 2021年 第23卷 第4期   页码 37-44 doi: 10.15302/J-SSCAE-2021.04.005

摘要：

冷链储运技术装备是维持生鲜农产品品质并提高流通效率的重要途径，对于保障食品安全、提高农业收入具有重要意义。本文在分析我国冷链储运技术装备需求的基础上，梳理了我国冷链储运技术装备的发展现状，总结了我国生鲜农产品冷链储运技术装备相比于发达国家存在的差距与问题；基于德尔菲法与实地调研，研判了我国生鲜农产品冷链储运技术装备发展的关键技术、重点任务、重大工程。针对我国生鲜农产品冷链储运技术装备存在的产地专业化预冷设施匮乏、冷藏运输装备匮乏、速冻技术装备落后、关键技术研发滞后、冷冻冷藏设施建设不规范、冷链基础设施建设不足等问题，提出了发展规划“三步走”技术路线，以期我国生鲜农产品冷链储运技术装备到 2025 年能够初步实现高效化与标准化，到 2035 年能够实现信息化与智能化，到 2050 年能够实现智慧化与无人化。

关键词： 生鲜农产品，冷链储运技术，冷链装备，德尔菲法    

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Expression and clinical implication of PRL-1 and PRL-3 in transitional cell carcinoma of bladder

Bin HAO, Changwei LIU, Huixiang LI

《医学前沿（英文）》 2009年 第3卷 第2期   页码 197-203 doi: 10.1007/s11684-009-0036-3

摘要： The mRNA and protein expression of phosphatase of regenerating liver 1 (PRL-1) and phosphatase of regenerating liver 3 (PRL-3) in transitional cell carcinoma of bladder (BTCC) and normal epithelia of bladder was investigated, and the relationship between the BTCC and pathological changes was clarified. The expression of PRL-1 and PRL-3 mRNA was detected by using reverse transcription polymerase chain reaction (RT-PCR) in 30 cases of BTCC and 10 cases of normal bladder, and the expression of PRL-1 and PRL-3 protein was checked by using immunohistochemistry in 30 cases of BTCC and 15 cases of normal bladder. The expression levels of PRL-1 and PRL-3 mRNA and protein were higher in BTCC than those in normal bladder epithelia ( <0.05). The increased expression of PRL-1 and PRL-3 mRNA and protein was detectable in deep invasion and metastasis of BTCC ( <0.05). There was no correlation between the expression of PRL-1 and PRL-3 and gender, age or recurrence of BTCC (all >0.05). A significantly positive correlation was found between PRL-1 and PRL-3 in BTCC ( <0.05). PRL-1 and PRL-3 are expressed consistently and may contribute to the growth, differentiation, invasion and metastasis of BTCC.

关键词： transitional cell carcinoma of bladder     phosphatase of regenerating liver 1     phosphatase of regenerating liver 3     reverse transcription polymerase chain reaction     immunohistochemistry    

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标题 作者 时间 类型 操作

An assessment of China-Japan-Korea Free Trade Agreement’s economic and environmental impacts on China

Zhaoyang LIU, Xianqiang MAO, Wei TANG, Tao HU, Peng SONG

期刊论文

Continuous reaction performances of benzene alkylation with long chain olefins catalyzed by ionic liquid

QIAO Congzhen, LI Chengyue

期刊论文

A systemic review of hydrogen supply chain in energy transition

期刊论文

Rosin side chain type catalyst-free vitrimers with high cross-link density, mechanical strength, and

期刊论文

Lignin-based polymer with high phenolic hydroxyl group content prepared by the alkyl chain bridging method

期刊论文

A case study on sample average approximation method for stochastic supply chain network design problem

Yuan WANG, Ruyan SHOU, Loo Hay LEE, Ek Peng CHEW

期刊论文

Using pyrosequencing and quantitative PCR to analyze microbial communities

Husen ZHANG

期刊论文

An integrated assessment method of urban drainage system: A case study in Shenzhen City, China

DONG Xin, ZENG Siyu, CHEN Jining, ZHAO Dongquan

期刊论文

单自由度平面闭链机构构型方法的研究

张美麟,张晔,杨治义

期刊论文

API-based assessment on urban air environment bearing capability in China

Jinnan WANG,Jing ZHANG,Hongqiang JIANG,Yaling LU

期刊论文

Synthesis and characterization of magnesium hydroxide by batch reaction crystallization

Xingfu SONG, Shuying SUN, Dengke ZHANG, Jin WANG, Jianguo YU

期刊论文

Liquefaction assessment using microtremor measurement, conventional method and artificial neural network

Sadegh REZAEI,Asskar Janalizadeh CHOOBBASTI

期刊论文

一种通过检测特定粪便微生物群来评估人体肠道微生物稳态的方法

Zhongwen Wu, Xiaxia Pan, Yin Yuan, Pengcheng Lou, Lorina Gordejeva, Shuo Ni, Xiaofei Zhu, Bowen Liu, Lingyun Wu, Lanjuan Li, Bo Li

期刊论文

生鲜农产品冷链储运技术装备发展研究

杨天阳,田长青,刘树森

期刊论文

Expression and clinical implication of PRL-1 and PRL-3 in transitional cell carcinoma of bladder

Bin HAO, Changwei LIU, Huixiang LI

期刊论文