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A projected Newton algorithm based on chemically allowed interval for chemical equilibrium computations

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 25-37页

作者： Hongbin Lu Shaohui Tao Xiaoyan Sun li Xia shuguang Xiang Institute of Process Systems Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China

The chemical equilibrium equations utilized in reactive transport modeling are complex and nonlinear,and are typically solved using the Newton-Raphson method.Although this algorithm is known for its quadratic convergence near the solution,it is less effective far from the solution,especially for ill-conditioned problems.In such cases,the algorithm may fail to converge or require excessive iterations.To address these limitations,a projected Newton method is introduced to incorporate the concept of projection.This method constrains the Newton step by utilizing a chemically allowed interval that generates feasible descending iterations.Moreover,we utilize the positive continuous fraction method as a preconditioning technique,providing reliable initial values for solving the algorithms.The numerical results are compared with those derived using the regular Newton-Raphson method,the Newton-Raphson method based on chemically allowed interval updating rules,and the bounded variable least squares method in six different test cases.The numerical results highlight the robustness and efficacy of the proposed algorithm.

关键词： chemical equilibrium reactive transport modeling numerical methods projected Newton method

Intake of tobacco nitrosamines of smokers in various provinces of China and their cancer risk:A meta-analysis

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Journal of Environmental Sciences 2024年第7期141卷 249-260页

作者： Xiao li Zhiwei Ye Jun Wang Pengfei lin Xiaojin Zhang shuguang Xie Chao Chen Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhouJiangsu 215163China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Shenzhen Key Laboratory of Organic Pollution Prevention and Control State Key Laboratory of Urban Water Resource and EnvironmentHarbin Institute of TechnologyShenzhen 518055China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Science and EngineeringPeking UniversityBeijing 100871China

Nitrosamines are a class of carcinogens which have been detected widely in food,water,some pharmaceuticals as well as tobacco.The objectives of this paper include reviewing the basic information on tobacco consumption and nitrosamine contents,and assessing the health risks of tobacco nitrosamines exposure to Chinese smokers.We searched the publications in English from“Web of Science”and those in Chinese from the“China National Knowledge Infrastructure”in 2022 and collected 151 literatures with valid information.The content of main nitrosamines in tobacco,including 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone(NNK),N-nitrosonornicotine(NNN),N-nitrosoanatabine(NAT),N-nitrosoanabasine(NAB),total tobacco-specific nitrosamines(TSNA),and N-nitrosodimethylamine(NDMA)were summarized.The information of daily tobacco consumption of smokers in 30 provinces of China was also collected.Then,the intakes of NNN,NNK,NAT,NAB,TSNAs,and NDMA via tobacco smoke were estimated as 1534ng/day,591 ng/day,685 ng/day,81 ng/day,2543 ng/day,and 484 ng/day by adult smokers in30 provinces,respectively.The cancer risk(CR)values for NNN and NNK inhalation intake were further calculated as 1.44×10^(-5)and 1.95×10^(-4).The CR value for NDMA intake via tobacco smoke(inhalation:1.66×10^(-4))indicates that NDMA is similarly dangerous in tobacco smoke when compared with the TSNAs.In China,the CR values caused by average nitrosamines intake via various exposures and their order can be estimated as the following:smoke(3.75×10^(-4))>food(1.74×10^(-4))>drinking water(1.38×10^(-5)).Smokers in China averagely suffer 200%of extra cancer risk caused by nitrosamines in tobacco when compared with non-smokers.

关键词： N-nitrosamine Tobacco Cancer risk Tobacco specific nitrosamines(TSNAs) N-nitrosodimethylamine(NDMA)

Assembling S-scheme heterojunction between basic bismuth nitrate and bismuth tungstate with promoting charges’separation for accelerated photocatalytic sulfamethazine degradation

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Journal of Materials Science & Technology 2024年第4期171卷 185-197页

作者： Wenhan Chen Meng Dai li Xiang Shan Zhao shuguang Wang Zuoli He Shandong Key Laboratory of Water Pollution Control and Resource Reuse Shandong Key Laboratory of Environmental Processes and HealthSchool of Environmental Science and EngineeringShandong UniversityQingdao 266237China CEDAR Knight Cancer InstituteSchool of MedicineOregon Health and Science UniversityPortlandOR 97201United States Weihai Research Institute of Industrial Technology of Shandong University Shandong UniversityWeihai 264209China

The S-scheme heterojunction has garnered increasing attention due to its remarkable oxidation capacity and efficient separation of photogenerated carriers.In this study,a one-pot glycerol-assisted hydrothermal process was utilized to successfully synthesize S-scheme heterojunction photocatalysts comprising basic bismuth nitrate(BBN)and bismuth tungstate(BWO).Interestingly,the BBN/BWO heterogeneous photo-catalysts exhibited the highest photocatalytic properties.The optimized product achieved the degradation of sulfamethazine(SMZ)within 1 h,with a kinetic constant(k)value of 0.05818 min^(−1).The degradation process was influenced significantly by·O^(2)−and h^(+)species.To determine the degradation pathway of SMZ in the presence of BBN/BWO-0.6,liquid chromatography-mass spectrometry(LC-MS)analysis was performed,which revealed a decrease in the toxicity of intermediates and products.The enhanced pho-tocatalytic activity can be attributed to the internal electric field(IEF)of the S-scheme heterojunction between BBN and BWO,effectively promoting the separation of photogenerated carriers.This research presents a viable approach for developing S-scheme heterojunctions in SMZ photodegradation and other environmental applications.

关键词： Photocatalysis S-scheme Heterojunction Bi_(2)WO_(6) Sulfamethazine

Design method of extractant for liquideliquid extraction based on elements and chemical bonds

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Chinese Journal of Chemical Engineering 2024年第4期68卷 193-202页

作者： Yuwen Wei Chunling Zhang Yue Zhang lili Wang li Xia Xiaoyan Sun shuguang Xiang Institute of Process System Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China Yantai Guobang Chemical Machinery Technology Co. Ltd.Yantai 264002China

In the petrochemical industry process,the relative volatility between the components to be separated is close to one or the azeotrope that systems are difficult to separate.liquideliquid extraction is a common and effective separation method,and selecting an extraction agent is the key to extraction technology research.In this paper,a design method of extractants based on elements and chemical bonds was proposed.A knowledge-based molecular design method was adopted to pre-select elements and chemical bond groups.The molecules were automatically synthesized according to specific combination rules to avoid the problem of“combination explosion”of molecules.The target properties of the extractant were set,and the extractant meeting the requirements was selected by predicting the correlation physical properties of the generated molecules.Based on the separation performance of the extractant in liquideliquid extraction and the relative importance of each index,the fuzzy comprehensive evaluation membership function was established,the analytic hierarchy process determined the mass ratio of each index,and the consistency test results were passed.The results of case study based on quantum chemical analysis demonstrated that effective determination of extractants for the analysis of benzeneecyclohexane systems.The results unanimously prove that the method has important theoretical significance and application value.

关键词： Molecular design Element and chemical bonds Molecular simulation Thermodynamics Solvent extraction

Hippo(YAP)-autophagy axis protects against hepatic ischemia-reperfusion injury through JNK signaling

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Chinese Medical Journal 2024年第6期137卷 657-668页

作者： shuguang Zhu Xiaowen Wang Haoqi Chen Wenfeng Zhu Xuejiao li Ruiwen Cui Xiaomeng Yi Xiaolong Chen Hua li Genshu Wang Department of Hepatic Surgery Liver TransplantationThe Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510630China Department of Hepatology lab The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510630China Department of General Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510630China Department of Organ Transplantation The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510630China Department of Renal Transplantation Guangdong Provincial Hospital of Chinese MedicineGuangzhouGuangdong 510630China Department of Surgical Intensive Care Unit The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510630China Department of Hepatic Surgery Liver TransplantationGuangdong Provincial Hospital of Chinese MedicineGuangzhouGuangdong 510630China

Background:Hepatic ischemia-reperfusion injury(HIRI)remains a common complication during liver transplantation(LT)in patients.As a key downstream effector of the Hippo pathway,Yes-associated protein(YAP)has been reported to be involved in various physiological and pathological processes.However,it remains elusive whether and how YAP may control autophagy activation during ischemia-reperfusion.Methods:Human liver tissues from patients who had undergone LT were obtained to evaluate the correlation between YAP and autophagy activation.Both an in vitro hepatocyte cell line and in vivo liver-specific YAP knockdown mice were used to establish the hepatic ischemia-reperfusion models to determine the role of YAP in the activation of autophagy and the mechanism of regulation.Results:Autophagy was activated in the post-perfusion liver grafts during LT in patients,and the expression of YAP positively correlated with the autophagic level of hepatocytes.liver-specific knockdown of YAP inhibited hepatocytes autophagy upon hypoxia-reoxygenation and HIRI(Pling through binding to the transcriptional enhanced associate domain(TEAD).Conclusions:YAP protects against HIRI by inducing autophagy via JNK signaling that suppresses the apoptosis of hepatocytes.Targeting Hippo(YAP)-JNK-autophagy axis may provide a novel strategy for the prevention and treatment of HIRI.

关键词： YAP-signaling proteins Autophagy c-Jun N-terminal kinase Ischemia-reperfusion injury liver transplantation

Mapping out the reaction network of humin formation at the initial stage of fructose dehydration in water

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Green Energy & Environment 2024年第6期9卷 1016-1026页

作者： Xing Fu Yexin Hu Ping Hu Hui li shuguang Xu liangfang Zhu Changwei Hu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan610064China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengduSichuan611137China

The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural(HMF)in biorefinery.Here,a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water is delineated by combined experimental,spectroscopic,and theoretical studies.Three bimolecular reaction pathways to build up soluble humins are demonstrated.That is,the intermolecular etherification of β-furanose at room temperature initiates the C12 path,whereas the C-C cleavage of a-furanose at 130-150℃ leads to C11 path,and that of open-chain fructose at 180℃ to C11' path.The successive intramolecular dehydrations and condensations of the as-formed bimolecular intermediates lead to three types of soluble humins.We show that the C12 path could be restrained by using HCl or AlCl_(3) catalyst,and both the C12 and C110 paths could be effectively inhibited by adding THF as a co-solvent or accelerating heating rate via microwave heating.

关键词： Carbohydrates 5-hydroxymethylfurfural Reaction network Soluble humins Tautomer

linking deep CO2 outgassing to cratonic destruction

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National Science Review 2022年第6期9卷 12-22页

作者： Zhao-Xue Wang Sheng-Ao liu shuguang li Di liu Jingao liu State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Outgassing of carbon dioxide from the Earth’s interior regulates the surface climate through deep time.Here we examine the role of cratonic destruction in mantle CO2outgassing via collating and presenting new data for Paleozoic kimberlites, Mesozoic basaltic rocks and their mantle xenoliths from the eastern North China Craton(NCC), which underwent extensive destruction in the early Cretaceous. High Ca/Al and low Ti/Eu and δ26Mg are widely observed in lamprophyres and mantle xenoliths, which demonstrates that the cratonic lithospheric mantle(CLM) was pervasively metasomatized by recycled carbonates.Raman analysis of bubble-bearing melt inclusions shows that redox melting of the C-rich CLM produced carbonated silicate melts with high CO2content. The enormous quantities of CO2in these magmas,together with substantial CO2degassing from the carbonated melt–CLM reaction and crustal heating,indicate that destruction of the eastern NCC resulted in rapid and extensive mantle CO2emission, which partly contributed to the early Cretaceous greenhouse climate episode.

关键词： carbonate metasomatism lithospheric mantle CO_2 outgassing deep carbon cycling cratonic destruction North China Craton

Optimization of fracturing parameters for tight oil production based on genetic algorithm

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Petroleum 2022年第2期8卷 252-263页

作者： Dali Guo Yunwei Kang Zhiyong Wang Yunxiang Zhao shuguang li School of Science Southwest Petroleum UniversityChengdu610500China Engineering Technology Research Institute of XDEC Karamay834000China School of Science Civil Aviation Flight University of ChinaDeyang618000China China United Coalbed Methane National Engineering Research Center Co. Ltd.Beijing100095China

It is difficult to determine the main controlling factors of tight oil production.In addition to the problem of uncontrollable prediction accuracy,the numerical prediction model established by the main controlling factors will also make the correctly predicted low production samples lose the value of development.Applying the optimization algorithm with fast convergence speed and global optimization to optimize the controllable parameters in the high-precision numerical prediction model can effectively improve the productivity of low production wells with timeliness,and bring greater economic value while saving development cost.Using PCA-GRA method,the sample weight and the weighted correlation ranking results of parameters affecting tight oil production were obtained.Thereupon then the main controlling factors of tight oil production were determined.Then we set up a BP neural network model with by taking the main controlling factors as input and tight oil production as output.The prediction effect of the network was good and can be put into use.The results of sensitivity analysis showed that the network was stable,and the total fracturing fluid volume had the greatest impact on the production of tight oil.Finally,by using genetic algorithm,we optimized the fracturing parameters of all low production well samples in the field data.Combined with the fracturing parameters of all high production well samples and the optimized fracturing parameters of low production wells,the optimal interval of fracturing parameters was given,which can provide guidance for the field fracturing operation.

关键词： PCA-GRA method Main controlling factors BP neural network Genetic algorithm Optimization of fracturing parameters

Formation of defects in selective laser melted Inconel 718 and its correlation with mechanical properties through dimensionless numbers

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Science China(Physics,Mechanics & Astronomy) 2022年第5期65卷 58-74页

作者： Zhiwei Luo Zekun Wang Zhenyu Yan Jing Chen shuguang li Moubin liu Capital Aerospace Machinery Co.Ltd. Beijing 100706China State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering SciencePeking UniversityBeijing 100871China College of Engineering Peking UniversityBeijing 100187China Nanchang Innovation Institute Peking UniversityNanchang 330008China

This paper presents a profound study on the formation of three typical types of defects(i.e.,lack of fusion,keyholes,and gas pores)observed in selective laser melting(SLM)printed Inconel 718 samples,along with their correlations with mechanical properties of the samples.Computed tomography,scanning electron microscopy,and mechanical property tests revealed that the three types of defects fall into three stages of porosity evolution classified by recently-proposed dimensionless numbersηm(melting efficiency)andηv(vaporization efficiency).Meanwhile,experimental tests verified that the mechanical properties of products,such as strength and elongation,are remarkably sensitive to lack of fusion.However,these properties are slightly affected by the keyholes and gas pores.An optimal process window characterized by dimensionless numbers is realized by adjusting the processing parameters and employing different powders.This process window allows products to have relatively low defects and high mechanical performances.A quantitative relation between processing parameters,dimensionless numbers,defects,and mechanical properties is established based on these observations.This relation,along with the optimal process window,is believed to enhance the quality of SLM products of Inconel 718 alloy and can be further extended to SLM with other metal materials.

关键词： selective laser melting defects formation mechanical properties similarity criterion