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Molecular composition of low-temperature oxidation products of the heavy oil

Petroleum Science 2023年第5期20卷 3264-3271页

作者： Shuai Ma Yun-Yun Li Ri-Gu Su xu-sheng wang Jing-Jun Pan Quan Shi Guang-Zhi Liao Chun-Ming xu State Key Laboratory of Heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing102249China Engineering Technology Research Institute of PetroChina Xinjiang Oilfield Company Karamay834000XinjiangChina CAS Lanzhou Institute of Chemical Physics Lanzhou730000GansuChina PetroChina Exploration&Production Company Beijing100007China

Low-temperature oxidation(LTO)is the main reaction that affects fuel formation in the in-situ combustion process,which has important significance for the subsequent combustion propulsion and the successful extraction of crude oil.In this study,heavy oil was subjected to LTO reactions at different temperatures.Three types of reaction products with varying oxidation depths were characterized in terms of the number of oxygen atoms and the polarity of the molecule to reveal the low-temperature oxidation process of the heavy oil.Ketone compounds and acid polyoxides in the oil phase and deep oxidation products with a higher number of oxygen atoms in the coke were identified with increasing oxidation depth.The experimental results showed that the oxidation reaction of the heavy oil changed from kinetic-controlled to diffusion-controlled in the open oxidation system of the heavy oil as the oxidation depth increased.The oxidation reaction of the oil phase reached a maximum and stable value in oxygen content.The molecular compositions of the ketone compound and acid polyoxide did not change significantly with further increase in reaction temperature.The molecular compositions of the deep oxidation products with a higher number of oxygen atoms in the coke phase changed significantly.The coke precursor molecules with a lower oxygen content and condensation degree participated in the coke formation,and the oxidation reaction pathway and the complexity of the oxidation product component also increased.

关键词： Low-temperature oxidation In-situ combustion Heavy oil Coke precursor Molecular composition

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Thermal Resistance Testing Technology Research of Integration High Power-LED

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 106-110页

作者： Ping xue Chang-Hong Jia xu-sheng wang Hao Sun Optic & Electronic Engineering Research Center Harbin University of Science and Technology

In this paper,high-power LED with many integrated chips is used as thermal resistance analysis research object, and we do thermal resistance testing technology research on it. We put forward the thermocouple point contact test method. According to the principle that LED forward voltage changes with temperature,LED heat sink to surface temperature distribution is studied directly in the test,and then we analyze the thermal resistance of high-power LED with many integrated chips when its secondary packaging is introduced. This method makes the measurement of thermal resistance of LED more rapid and convenient. It provides an effective assessment method for the analysis of high power LED device design and engineering application.

关键词： thermal resistance junction temperature integrated high power LED cooling

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Improvement and Implementation of Embedded Fiber Bragg Grating Sensor Signal De-module

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 118-123页

作者： Hong-Min wang xu-sheng wang Chang-Hong Jia Kong-Qi Li Xiao-Fei Hu Hai-Qing Guo College of Automation Harbin University of Science and Technology

This paper focused on high-precision demodulation of wavelength shift of FBG sensor. Fiber tunable F-P filer was used as a demodulation method. 32-bit embedded processor ARM9-S3C2440 chip was used as the main controller and simulated annealing algorithm was realized on ARM to demodulate wavelength signal. Simulation results show that the simulated annealing algorithm is reliable to process analog signals on ARM chip and significant performance is achieved such as saving bandwidth,increasing the amounts of reusable fiber grating sensors in sensor system and speeding up data processing.

关键词： embedded fiber bragg grating simulated annealing algorithm

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Neuroprotective effect of the Chinese medicine Tiantai No.1 and its molecular mechanism in the senescence-accelerated mouse prone 8

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Neural Regeneration Research 2017年第2期12卷 301-306页

作者： Ying-hong Li xu-sheng wang Xiao-lin Chen Yu Jin Hong-bo Chen Xiu-qin Jia Yong-feng Zhang Zheng-zhi Wu First Affiliated Hospital of Shenzhen University (Shenzhen Second People's Hospital) Shenzhen Guangdong Province China School of Life Sciences Tsinghua University Beijing China Guangzhou Medical University Guangzhou Guangdong Province China Shenzhen Key Laboratory of Health Sciences and Technology Graduate School at Shenzhen Tsinghua University Beijing China

Tiantai No.1, a Chinese medicine predominantly composed of powdered Rhizoma Gastrodiae, Radix Ginseng, and Ginkgo leaf at a ratio of 2：1：2 and dissolved in pure water, is neuroprotective in animal models of various cognitive disorders, but its molecular mechanism remains unclear. We administered Tiantai No.1 intragastrically to senescence-accelerated mouse prone 8（SAMP8） mice（a model of Alzheimer＇s disease） at doses of 50, 100 or 150 mg/kg per day for 8 weeks and evaluated their behavior in the Morris water maze and expression of Alzheimer＇s disease-related proteins in the brain. Tiantai No.1 shortened the escape latency in the water maze training trials, and increased swimming time in the target quadrant during the spatial probe test, indicating that Tiantai No.1 improved learning and memory in SAMP8 mice. Immunohistochemistry revealed that Tiantai No.1 restored the proliferation potential of Ki67-positive cells in the hippocampus. In addition, mice that had received Tiantai No.1 had fewer astrocytes, and less accumulation of amyloid-beta and phosphorylated tau. These results suggest that Tiantai No.1 is neuroprotective in the SAMP8 mouse model of Alzheimer＇s disease and acts by restoring neuronal number and proliferation potential in the hippocampus, decreasing astrocyte infiltration, and reducing the accumulation of amyloid-beta and phosphorylated tau.

关键词： nerve regeneration neuroprotective effects Alzheimer＇s disease Tiantai No.1 SAMP8 amyloid-beta autophagy-lysosome pathway ubiquitin proteasome pathway tau phosphorylation neuronal apoptosis astrocytosis neural regeneration

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Perception of fundamental science to boost lithium metal anodes toward practical application

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Green Energy & Environment 2024年第3期9卷 454-472页

作者： Jinkun wang Li wang Hong xu Li sheng Xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China

As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference electrodes.Although lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium metal.To pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are provided.Firstly,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic properties.Subsequently,the electrochemical properties of lithium metal are reviewed.Numerous important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in detail.Approaches to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed.

关键词： Lithium Cluster Crystal Physicochemical property Fundamental science

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Green manufacturing for achieving carbon neutrality goal requires innovative technologies:A bibliometric analysis from 1991 to 2022

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Journal of Environmental Sciences 2024年第6期140卷 255-269页

作者： sheng Zhang Xintian wang Jiayu xu Qinqin Chen Meng Peng Jiming Hao School of Environment Tsinghua UniversityBeijing 100084China School of Environment&Natural Resources Renmin University of ChinaBeijing 100872China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

Recent years have seen a significant increase in interest in green manufacturing as a key driver of global carbon-neutral efforts and sustainable development.To find the research hotspots of green manufacturing and reveal future research trends,this study reviewed and analyzed research articles from the Web of Science database on green manufacturing from1991 to 2022 using a bibliometric method.The findings indicate a significant rise in the number of articles related to green manufacturing since the 2010s.Moreover,there has been an increase in the involvement of scholars from developing countries such as China and India in this field.Based on the literature review and bibliometric cluster analysis on green manufacturing,we believed that future research may continue following the lines of intelligent technology integration,adoption of frontier engineering techniques,and industry development in line with carbon reduction targets.A framework for future green manufacturing development is proposed,with a focus on Chinese policies.The framework could provide policy implications for developing countries looking to pursue opportunities for development in green manufacturing.

关键词： Green manufacturing Carbon neutrality Sustainable development Innovative technologies China

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The biological functions and metabolic pathways of valine in swine

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Journal of Animal Science and Biotechnology 2024年第1期15卷 20-34页

作者： Chuni wang Yao Peng Yiru Zhang Juan xu sheng Jiang Leli wang Yulong Yin Institute of Subtropical Agriculture Chinese Academy of SciencesChangshaChina Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation College of Life SciencesHunan Normal UniversityChangshaChina Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjinChina

Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry.

关键词： Additional dosage Biological function Metabolic pathway Pig Valine

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A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1342-1357页

作者： sheng Qi Rui wang Tao Zhang xu Yang Ruiqing Sun Ling wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China Xiangjiang Laboratory Changsha 410205China College of Computer National University of Defense TechnologyChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China IEEE

Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.As a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec separately.Nevertheless,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables Mask.However,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is optimized.In data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between data.Inspired by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these SLMOPs.TELSO mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast convergence.Experi-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed.

关键词： Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.

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Transverse mode-coupling instability with longitudinal impedance

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Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： Hai-sheng xu Chun-Tao Lin Na wang Jing-Ye xu Yuan Zhang Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle loss.The mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were included.We performed computations for the circular electron-positron collider(CEPC)and observed a similar phenom-enon.Systematic studies on the influence of longitudinal impedance on the TMCI threshold were conducted.We concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI threshold.Additionally,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

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Prediction of Anoxic Sulfide Biooxidation Under Various HRTs Using Artificial Neural Networks

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Biomedical and Environmental Sciences 2007年第5期20卷 398-403页

作者： QAISAR MAHMOOD PING ZHENG DONG-LEI WU xu-sheng wang HAYAT YOUSAF EJAZ UL-ISLAM MUHAMMAD JAFFAR HASSAN GHULAM JILANI MUHAMMAD RASHID AZIM Department of Environmental Engineering College of Environment and Resource Science Zhejiang University Hangzhou 310029 Zhejiang China Institute of Statistical Genetics Zhejiang University Hangzhou 310029 Zhejiang China tUniversity of Arid Agriculture Rawalpindi Pakistan University of Arid Agriculture Rawalpindi Pakistan Federal Government Post-graduate College Sector H-8 Islamabad Pakistan

Objective During present investigation the data of a laboratory-scale anoxic sulfide oxidizing （ASO） reactor were used in a neural network system to predict its performance. Methods Five uncorrelated components of the influent wastewater were used as the artificial neural network model input to predict the output of the effluent using back-propagation and general regression algorithms. The best prediction performance is achieved when the data are preprocessed using principal components analysis （PCA） before they are fed to a back propagated neural network. Results Within the range of experimental conditions tested, it was concluded that the ANN model gave predictable results for nitrite removal from wastewater through ASO process. The model did not predict the formation of sulfate to an acceptable manner. Conclusion Apart from experimentation, ANN model can help to simulate the results of such experiments in finding the best optimal choice for ASO based denitrification. Together with wastewater collection and the use of improved treatment systems and new technologies, better control of wastewater treatment plant （WTP） can lead to more effective maneuvers by its operators and, as a consequence, better effluent quality.

关键词： Artificial neural networks Effluent sulfide prediction Effluent nitrite prediction Principal components analysis Wastewater treatment ASO reactor

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