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参数估计 2

可靠性；维修性；保障性；指标量化 2

城市规划 2

实时荧光定量PCR 2

2R-1C模型；嵌入式系统；参数估计；非迭代方法；二次型 1

3-酰基硫代四酸 1

Aphanomyces euteiches 1

ATP荧光检测 1

Arrhenius模型 1

COVID-19 1

CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

F-N图 1

ICI）；最大似然估计（maximum likelihood estimation 1

LNG 1

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N-糖基化 1

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Quantitative analysis of CO

Xianbing LIU, Can WANG

《环境科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 12-19 doi: 10.1007/s11783-009-0011-x

摘要： The increasing volume of CO embodiment in international trade adds a layer of complexity to environmental policies and has raised arguments on the traditional production based responsibility for CO emissions. In order to help understand the quantity of CO embodiment in trade and its policy implications, this paper gives observations to recently emerging literatures that quantitatively discuss CO embodiment in trade. The analytical approaches share the principle of using input and output modeling but vary dramatically in study boundary and estimation accuracy. The calculations can be roughly categorized into three types: direct quantification of CO embodiments in multiregional trade, direct quantification of CO embodiment in bilateral trade, and indirect analysis by comparing the scenarios with or without trade. The practical estimations strongly rely on trade partner selection and data availability. An obvious imbalance of net CO embodiment in the commodity trade between major developed countries and developing economies as a whole was confirmed by these literatures. Carbon taxes and other possible limitations on CO emissions have been addressed. The consistency across the calculations could be enhanced by systematic analyses in more detail to convince the international community to take binding commitments for the reduction of global CO emissions.

关键词： CO2 embodiment     international trade     quantitative estimation     analytical approach    

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Estimation of photolysis half-lives of dyes in a continuous-flow system with the aid of quantitative

Davoud BEIKNEJAD,Mohammad Javad CHAICHI

《环境科学与工程前沿（英文）》 2014年 第8卷 第5期   页码 683-692 doi: 10.1007/s11783-014-0680-y

摘要： In this paper the photolysis half-lives of the model dyes in water solutions and under ultraviolet (UV) radiation were determined by using a continuous-flow spectrophotometric method. A quantitative structure-property relationship (QSPR) study was carried out using 21 descriptors based on different chemometric tools including stepwise multiple linear regression (MLR) and partial least squares (PLS) for the prediction of the photolysis half-life ( ) of dyes. For the selection of test set compounds, a K-means clustering technique was used to classify the entire data set, so that all clusters were properly represented in both training and test sets. The QSPR results obtained with these models show that in MLR-derived model, photolysis half-lives of dyes depended strongly on energy of the highest occupied molecular orbital ( ), largest electron density of an atom in the molecule ( ) and lipophilicity (log ). While in the model derived from PLS, besides aforementioned and descriptors, the molecular surface area ( ), molecular weight ( ), electronegativity ( ), energy of the second highest occupied molecular orbital ( ) and dipole moment ( ) had dominant effects on logt values of dyes. These were applicable for all classes of studied dyes (including monoazo, disazo, oxazine, sulfonephthaleins and derivatives of fluorescein). The results were also assessed for their consistency with findings from other similar studies.

关键词： dye     photolysis half-life     quantitative structure-property relationship     continuous-flow     stepwise multiple linear regression     partial least squares    

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A computational toolbox for molecular property prediction based on quantum mechanics and quantitative

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 152-167 doi: 10.1007/s11705-021-2060-z

摘要： Chemical industry is always seeking opportunities to efficiently and economically convert raw materials to commodity chemicals and higher value-added chemical-based products. The life cycles of chemical products involve the procedures of conceptual product designs, experimental investigations, sustainable manufactures through appropriate chemical processes and waste disposals. During these periods, one of the most important keys is the molecular property prediction models associating molecular structures with product properties. In this paper, a framework combining quantum mechanics and quantitative structure-property relationship is established for fast molecular property predictions, such as activity coefficient, and so forth. The workflow of framework consists of three steps. In the first step, a database is created for collections of basic molecular information; in the second step, quantum mechanics-based calculations are performed to predict quantum mechanics-based/derived molecular properties (pseudo experimental data), which are stored in a database and further provided for the developments of quantitative structure-property relationship methods for fast predictions of properties in the third step. The whole framework has been carried out within a molecular property prediction toolbox. Two case studies highlighting different aspects of the toolbox involving the predictions of heats of reaction and solid-liquid phase equilibriums are presented.

关键词： molecular property     quantum mechanics     quantitative structure-property relationship     heat of reaction     solid-liquid phase equilibrium    

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Erratum to: 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3期   页码 488-488 doi: 10.1007/s11783-011-0342-2

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Application of quantum chemical descriptors into quantitative structure-property relationship models

Yueping BAO, Qiuying HUANG, Wenlong WANG, Jiangjie XU, Fan JIANG, Chenghong FENG

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 505-511 doi: 10.1007/s11783-011-0318-2

摘要： Quantitative structure-property relationship (QSPR) models were developed for prediction of photolysis half-life ( ) of polychlorinated biphenyls (PCBs) in water under ultraviolet (UV) radiation. Quantum chemical descriptors computed by the PM3 Hamiltonian software were used as independent variables. The cross-validated value for the optimal QSPR model is 0.966, indicating good prediction capability for lg values of PCBs in water. The QSPR results show that the largest negative atomic charge on a carbon atom ( ) and the standard heat of formation (Δ ) have a dominant effect on values of PCBs. Higher values or lower Δ values of the PCBs leads to higher lg values. In addition, the lg values of PCBs increase with the increase in the energy of the highest occupied molecular orbital values. Increasing the largest positive atomic charge on a chlorine atom and the most positive net atomic charge on a hydrogen atom in PCBs leads to the decrease of lg values.

关键词： photolysis     polychlorinated biphenyls (PCBs)     quantitative structure-property relationships (QSPRs)     quantum chemical descriptors    

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Design and use of group-specific primers and probes for real-time quantitative PCR

Juntaek LIM, Seung Gu SHIN, Seungyong LEE, Seokhwan HWANG

《环境科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 28-39 doi: 10.1007/s11783-011-0302-x

摘要： Real-time quantitative polymerase chain reaction (qPCR) has gained popularity as a technique to detect and quantify a specific group of target microorganisms from various environmental samples including soil, water, sediments, and sludge. Although qPCR is a very useful technique for nucleic acid quantification, accurately quantifying the target microbial group strongly depends on the quality of the primer and probe used. Many aspects of conducting qPCR assays have become increasingly routine and automated; however, one of the most important aspects, designing and selecting primer and probe sets, is often a somewhat arcane process. In many cases, failed or non-specific amplification can be attributed to improperly designed primer-probe sets. This paper is intended to provide guidelines and general principles for designing group-specific primers and probes for qPCR assays. We demonstrate the effectiveness of these guidelines by reviewing the use of qPCR to study anaerobic processes and biologic nutrient removal processes. qPCR assays using group-specific primers and probes designed with this method, have been used to successfully quantify 16S ribosomal Ribonucleic Acid (16S rRNA) gene copy numbers from target methanogenic and ammonia- oxidizing bacteria in various laboratory- and full-scale biologic processes. Researchers with a good command of primer and probe design can use qPCR as a valuable tool to study biodiversity and to develop more efficient control strategies for biologic processes.

关键词： absolute quantification     design guideline     primer     probe     real-time quantitative polymerase chain reaction (qPCR)    

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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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Intelligent algorithm for optimal meter placement and bus voltage estimation in ring main distribution

L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY

《能源前沿（英文）》 2012年 第6卷 第1期   页码 47-56 doi: 10.1007/s11708-011-0159-5

摘要： The advancement in power distribution system poses a great challenge to power engineering researchers on how to best monitor and estimate the state of the distribution network. This paper is executed in two stage processes. The first stage is to identify the optimal location for installation of monitoring instrument with minimal investment cost. The second stage is to estimate the bus voltage magnitude, where real time measurement is conducted and measured through identified meter location which is more essential for decision making in distribution supervisory control and data acquisition system (DSCADA). The hybrid intelligent technique is applied to execute the above two algorithms. The algorithms are tested with institute of electrical and electronics engineers (IEEE) and Tamil Nadu electricity board (TNEB) benchmark systems. The simulated results proves that the swarm tuned artificial neural network (ANN) estimator is best suited for accurate estimation of voltage with different noise levels.

关键词： artificial intelligence     power distribution control     state estimation    

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An operating state estimation model for integrated energy systems based on distributed solution

Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG

《能源前沿（英文）》 2020年 第14卷 第4期   页码 801-816 doi: 10.1007/s11708-020-0687-y

摘要： In view of the disadvantages of the traditional energy supply systems, such as separate planning, separate design, independent operating mode, and the increasingly prominent nonlinear coupling between various sub-systems, the production, transmission, storage and consumption of multiple energy sources are coordinated and optimized by the integrated energy system, which improves energy and infrastructure utilization, promotes renewable energy consumption, and ensures reliability of energy supply. In this paper, the mathematical model of the electricity-gas interconnected integrated energy system and its state estimation method are studied. First, considering the nonlinearity between measurement equations and state variables, a performance simulation model is proposed. Then, the state consistency equations and constraints of the coupling nodes for multiple energy sub-systems are established, and constraints are relaxed into the objective function to decouple the integrated energy system. Finally, a distributed state estimation framework is formed by combining the synchronous alternating direction multiplier method to achieve an efficient estimation of the state of the integrated energy system. A simulation model of an electricity-gas interconnected integrated energy system verifies the efficiency and accuracy of the state estimation method proposed in this paper. The results show that the average relative errors of voltage amplitude and node pressure estimated by the proposed distributed state estimation method are only 0.0132% and 0.0864%, much lower than the estimation error by using the Lagrangian relaxation method. Besides, compared with the centralized estimation method, the proposed distributed method saves 5.42 s of computation time. The proposed method is more accurate and efficient in energy allocation and utilization.

关键词： integrated energy system     state estimation     electricity-gas coupling energy system     nonlinear coupling     distributed solution    

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Decoding and quantitative detection of antibiotics by a luminescent mixed-lanthanide-organic framework

《环境科学与工程前沿（英文）》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1589-5

摘要：

● A series of mixed-LOFs and portable LOF-fibers were synthesized.

关键词： Antibiotics     Sensor     Luminescence     Lanthanide-organic frameworks    

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Bayes estimation of residual life by fusing multisource information

Qian ZHAO, Xiang JIA, Zhi-jun CHENG, Bo GUO

《工程管理前沿（英文）》 2018年 第5卷 第4期   页码 524-532 doi: 10.15302/J-FEM-2018034

摘要：

Residual life estimation is essential for reliability engineering. Traditional methods may experience difficulties in estimating the residual life of products with high reliability, long life, and small sample. The Bayes model provides a feasible solution and can be a useful tool for fusing multisource information. In this study, a Bayes model is proposed to estimate the residual life of products by fusing expert knowledge, degradation data, and lifetime data. The linear Wiener process is used to model degradation data, whereas lifetime data are described via the inverse Gaussian distribution. Therefore, the joint maximum likelihood (ML) function can be obtained by combining lifetime and degradation data. Expert knowledge is used according to the maximum entropy method to determine the prior distributions of parameters, thereby making this work different from existing studies that use non-informative prior. The discussion and analysis of different types of expert knowledge also distinguish our research from others. Expert knowledge can be classified into three categories according to practical engineering. Methods for determining prior distribution by using the aforementioned three types of data are presented. The Markov chain Monte Carlo is applied to obtain samples of the parameters and to estimate the residual life of products due to the complexity of the joint ML function and the posterior distribution of parameters. Finally, a numerical example is presented. The effectiveness and practicability of the proposed method are validated by comparing it with residual life estimation that uses non-informative prior. Then, its accuracy and correctness are proven via simulation experiments.

关键词： residual life estimation     Bayes model     linear Wiener process    

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Thermal degradation kinetics and lifetime estimation for polycarbonate/polymethylphenylsilsesquioxane

Jiangbo WANG, Zhong XIN

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 167-171 doi: 10.1007/s11705-009-0006-y

摘要： The thermal degradation behaviors of polycarbonate/polymethylphenylsilsesquioxane (FRPC) composites were investigated by thermogravimetric analysis (TGA) under isothermal conditions in nitrogen atmosphere. The isothermal kinetics equation was used to describe the thermal degradation process. The results showed that activation energy ( ), in the case of isothermal degradation, was a quick increasing function of conversion (α) for polycarbonate (PC) but was a strong and decreasing function of conversion for FRPC. Under the isothermal condition, the addition of polymethylphenylsilsesquioxane (PMPSQ) retardanted the thermal degradation and enhanced the thermal stability of PC during the early and middle stages of thermal degradation. It also indicated a possible existence of a difference in nucleation, nuclei growth, and gas diffusion mechanism in the thermal degradation process between PC and FRPC. Meanwhile, the addition of PMPSQ influenced the lifetime of PC, but the composite still met the demand in manufacturing and application.

关键词： polycarbonate     polymethylphenylsilsesquioxane     thermal degradation kinetics     activation energy     lifetime    

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Quantitative proteomics revealed extensive microenvironmental changes after stem cell transplantation

《医学前沿（英文）》 2022年 第16卷 第3期   页码 429-441 doi: 10.1007/s11684-021-0842-9

摘要： The local microenvironment is essential to stem cell-based therapy for ischemic stroke, and spatiotemporal changes of the microenvironment in the pathological process provide vital clues for understanding the therapeutic mechanisms. However, relevant studies on microenvironmental changes were mainly confined in the acute phase of stroke, and long-term changes remain unclear. This study aimed to investigate the microenvironmental changes in the subacute and chronic phases of ischemic stroke after stem cell transplantation. Herein, induced pluripotent stem cells (iPSCs) and neural stem cells (NSCs) were transplanted into the ischemic brain established by middle cerebral artery occlusion surgery. Positron emission tomography imaging and neurological tests were applied to evaluate the metabolic and neurofunctional alterations of rats transplanted with stem cells. Quantitative proteomics was employed to investigate the protein expression profiles in iPSCs-transplanted brain in the subacute and chronic phases of stroke. Compared with NSCs-transplanted rats, significantly increased glucose metabolism and neurofunctional scores were observed in iPSCs-transplanted rats. Subsequent proteomic data of iPSCs-transplanted rats identified a total of 39 differentially expressed proteins in the subacute and chronic phases, which are involved in various ischemic stroke-related biological processes, including neuronal survival, axonal remodeling, antioxidative stress, and mitochondrial function restoration. Taken together, our study indicated that iPSCs have a positive therapeutic effect in ischemic stroke and emphasized the wide-ranging microenvironmental changes in the subacute and chronic phases.

关键词： ischemic stroke     microenvironment     induced pluripotent stem cells (iPSCs)     positron emission tomography (PET)     quantitative proteomics    

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Hierarchical parameter estimation of DFIG and drive train system in a wind turbine generator

Xueping PAN, Ping JU, Feng WU, Yuqing JIN

《机械工程前沿（英文）》 2017年 第12卷 第3期   页码 367-376 doi: 10.1007/s11465-017-0429-y

摘要：

A new hierarchical parameter estimation method for doubly fed induction generator (DFIG) and drive train system in a wind turbine generator (WTG) is proposed in this paper. Firstly, the parameters of the DFIG and the drive train are estimated locally under different types of disturbances. Secondly, a coordination estimation method is further applied to identify the parameters of the DFIG and the drive train simultaneously with the purpose of attaining the global optimal estimation results. The main benefit of the proposed scheme is the improved estimation accuracy. Estimation results confirm the applicability of the proposed estimation technique.

关键词： wind turbine generator     DFIG     drive train system     hierarchical parameter estimation method     trajectory sensitivity technique    

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iTRAQ-based quantitative analysis of cancer-derived secretory proteome reveals TPM2 as a potential diagnostic

null

《医学前沿（英文）》 2016年 第10卷 第3期   页码 278-285 doi: 10.1007/s11684-016-0453-z

摘要：

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. We aimed to find novel molecules as potential biomarkers for the early diagnosis of CRC. A serum-free conditioned medium was successfully collected from three pairs of CRC tissue and adjacent normal tissue. iTRAQ-based quantitative proteomic analysis was applied to compare the differences in secretome between primary CRC mucosa and adjacent normal mucosa. A total of 145 kinds of proteins were identified. Of these proteins, 29 were significantly different between CRC and normal tissue. Tropomyosin 2 β (TPM2) exhibited the most significant differences; as such, this protein was selected for further validation. Quantitative real-time PCR indicated that the mRNA expression of TPM2 significantly decreased in the CRC tissue compared with the paired adjacent normal tissue. Immunohistochemical analysis also confirmed that TPM2 was barely detected at protein levels in the CRC tissue. In summary, this study revealed potential molecules for future biomarker applications and provided an efficient approach for the differential analysis of cancer-associated secretome. TPM2 may be valuable for the early diagnosis of CRC.

关键词： iTRAQ     secretome     colorectal cancer     TPM2    

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标题 作者 时间 类型 操作

Quantitative analysis of CO

Xianbing LIU, Can WANG

期刊论文

Estimation of photolysis half-lives of dyes in a continuous-flow system with the aid of quantitative

Davoud BEIKNEJAD,Mohammad Javad CHAICHI

期刊论文

A computational toolbox for molecular property prediction based on quantum mechanics and quantitative

期刊论文

Erratum to: Using pyrosequencing and quantitative PCR to analyze microbial communities

Husen ZHANG

期刊论文

Application of quantum chemical descriptors into quantitative structure-property relationship models

Yueping BAO, Qiuying HUANG, Wenlong WANG, Jiangjie XU, Fan JIANG, Chenghong FENG

期刊论文

Design and use of group-specific primers and probes for real-time quantitative PCR

Juntaek LIM, Seung Gu SHIN, Seungyong LEE, Seokhwan HWANG

期刊论文

Using pyrosequencing and quantitative PCR to analyze microbial communities

Husen ZHANG

期刊论文

Intelligent algorithm for optimal meter placement and bus voltage estimation in ring main distribution

L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY

期刊论文

An operating state estimation model for integrated energy systems based on distributed solution

Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG

期刊论文

Decoding and quantitative detection of antibiotics by a luminescent mixed-lanthanide-organic framework

期刊论文

Bayes estimation of residual life by fusing multisource information

Qian ZHAO, Xiang JIA, Zhi-jun CHENG, Bo GUO

期刊论文

Thermal degradation kinetics and lifetime estimation for polycarbonate/polymethylphenylsilsesquioxane

Jiangbo WANG, Zhong XIN

期刊论文

Quantitative proteomics revealed extensive microenvironmental changes after stem cell transplantation

期刊论文

Hierarchical parameter estimation of DFIG and drive train system in a wind turbine generator

Xueping PAN, Ping JU, Feng WU, Yuqing JIN

期刊论文

iTRAQ-based quantitative analysis of cancer-derived secretory proteome reveals TPM2 as a potential diagnostic

null

期刊论文