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Science in China(Series F) 2009年第7期52卷 1113-1119页

作者： wang jiamin College of Management Long Island University 720 Northern Boulevard Brookville NY 11548 USA

In this paper we consider a retail service facility with cross-trained workers who can perform operations in both the front room and back room. Workers are brought from the back room to the front room and vice versa depending on the number of customers in the system. A loss of productivity occurs when a worker returns to the back room. Two problems are studied. In the first problem, given the number of workers available, we determine an optimal deterministic switching policy so that the expected number of customers in queue is minimized subject to a constraint ensuring that there is a sufficient workforce to fulfill the functions in the back room. In the second problem, the number of workers needed is minimized subject to an additional constraint requiring that the expected number of customers waiting in queue is bounded above by a given threshold value. Exact solution procedures are developed and illustrative numerical examples are presented.

关键词： queuing control optimization queuing theory Markov decision process

Insights into electrochemical CO_2 reduction on tin oxides from first-principles calculations

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Green Energy & Environment 2017年第2期2卷 168-171页

作者： Siwen wang jiamin wang Hongliang Xin Department of Chemical Engineering Virginia Polytechnic Institute and State University

Density functional theory calculations were used to unravel the mechanism of CO_2 electroreduction on SnO_x surfaces. Under highly reducing conditions(<-0.6 V vs. RHE), the SnO(101) surface with oxygen vacancies is likely the active phase for CO_2 reduction. We showed that the proton-electron transfer to adsorbed *CO_2 forming *OCHO, a key intermediate for producing HCOOH, is energetically more favorable than the formation of *COOH, justifying the selectivity trends observed on Sn-based electrocatalysts. With linear scaling relations, we propose the free formation energy of *CO_2 at the oxygen vacancy as the reactivity descriptor. By engineering the strain of the SnO(101) surface, the selectivity towards HCOOH can be further optimized at reduced overpotentials.

关键词： CO2 electroreduction Tin oxides Strain effect Scaling relations Density functional theory

Cesium-rubidium mineralization in Himalayan leucogranites

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Science China Earth Sciences 2023年第12期66卷 2827-2852页

作者： Fangyang HU Xiaochi LIU Shaoxiong HE jiamin wang Fuyuan WU Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 00029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper presents a study of a newly discovered pollucite-lepidolite-albite granite(PLAG)in the Himalayan leucogranite belt,which marks the first occurrence of pollucite,a major cesium silicate mineral,in the Himalayan orogenic belt(China).The rock appears at the northern part of the Gyirong pluton,coexisting with the tourmaline-bearing two-mica granite(TMG).Primary rare-metal minerals include lepidolite(Li),spodumene(Li),pollucite(Cs),cassiterite(Sn),and microlite(Ta).Micas,mainly lithian muscovite to lepidolite,contain 4.07 wt.%Li_2O and 0.76 wt.%Rb_2O on *** average Li_2O content of the spodumene is 7.95 wt.%.Pollucite not only has an average Cs_2O content of 34 wt.%,but also has an elevated Rb_2O content of about 0.16 wt.%.Notably,this granite attains industrial grades for rare metals,specifically with Li_2O,Rb_2O,and Cs_2O contents of 0.49–1.19 wt.%,0.12–0.24 wt.%,and 0.69–2.33 wt.%,*** results of magmatic accessory cassiterite and monazite indicated that the PLAG was formed at 19–18 Ma,slightly later than the TMG(22–20 Ma)of the Gyirong ***,these two types of granites may form within the same magmatic system considering their pulsating intrusive contact,formation ages,and whole-rock and mineral chemical ***,the abundant presence of pollucite suggests that the PLAG experienced high degrees of magmatic *** comparison to the Pusila spodumene pegmatite in the Himalaya and the Yashan topaz-lepidolite granite in Jiangxi,South China,the Gyirong PLAG exhibits different whole-rock and mineral compositions,resulting from differences in source materials and fractionation ***,the difference in fluorine(F)content may determine the degree of rare-metal element *** discovery of Gyirong PLAG highlights multiple stages and types of rare-metal mineralization in the Himalayan leucogranite belt,which is controlled by the South Tibetan Detachment *** Cs-bearing geyserite deposit exp

关键词： Himalaya Pollucite Lepidolite Leucogranite Rare-metal elements

Highly fractionated granites:Recognition and research

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Science China Earth Sciences 2017年第7期60卷 1201-1219页

作者： WU FuYuan LIU XiaoChi JI WeiQiang wang jiamin YANG Lei State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China College of Earth Sciences University of Chinese Academy of Sciences Beijing 100049 China

Granite is one of the most important components of the continental crust on our Earth; it thus has been an enduring studied subject in geology. According to present knowledge, granite shows a great deal of heterogeneity in terms of its texture,structure, mineral species and geochemical compositions at different scales from small dike to large batholith. However, the reasons for these variations are not well understood although numerous interpretations have been proposed. The key point of this debate is whether granitic magma can be effectively differentiated through fractional crystallization, and, if so, what kind of crystallization occurred during the magmatic evolution. Although granitic magma has high viscosity because of its elevated SiO2 content, we agree that fractional crystallization is effectively processed during its evolution based on the evidence from field investigation,mineral species and its chemical variations, and geochemical compositions. These data indicate that crystal settling by gravitation is not the only mechanism dominating granitic differentiation. On the contrary, flow segregation or dynamic sorting may be more important. Accordingly, granite can be divided into unfractionated, fractionated(including weakly fractionated and highly fractionated) and cumulated types, according to the differentiation degree. Highly fractionated granitic magmas are generally high in primary temperature or high with various volatiles during the later stage, which make the fractional crystallization much easier than the common granitic melts. In addition, effective magmatic differentiation can be also expected when the magma emplaced along a large scale of extensional structure. Highly fractionated granitic magma is easily contaminated by country rocks due to its relatively prolonged crystallization time. Thus, granites do not always reflect the characteristics of the source areas and the physical and chemical conditions of the primary magma. We proposed that h

关键词： Fractional crystallization Accumulation Highly fractionated granite Granitic magma Continental crustal evolution

The Himalayan Collisional Orogeny:A Metamorphic Perspective

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 1842-1866页

作者： wang jiamin WU Fuyuan ZHANG Jinjiang Gautam KHANAL YANG Lei State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth and Space Sciences Peking UniversityBeijing 100871China Department of Mines and Geology of Nepal Kathmandu 44600Nepal College of Earth Sciences Chengdu University of TechnologyChengdu 610059China

This paper introduces how crustal thickening controls the growth of the Himalaya by summarizing the P-T-t evolution of the Himalayan metamorphic *** Himalayan orogeny was divided into three *** 60–40 Ma:The Himalayan crust thickened to~40 km through Barrovian-type metamorphism(15–25°C/km),and the Himalaya rose from30°C/km).The three sub-sheets in the Himalayan metamorphic core extruded southward sequentially through imbricate thrusts of the Eo-Himalayan thrust,High Himalayan thrust,and Main Central thrust,and the Himalaya rose to≥5,000 *** 16–0 Ma:the mountain roots underwent localized delamination,causing asthenospheric upwelling and overprinting of the lower crust by ultra-high-temperature metamorphism(30–50°C/km),and the Himalaya reached the present elevation of~6,000 *** and imbricate thrusting dominated the Himalaya’growth and topographic rise,conforming to the critical taper wedge *** delamination of mountain roots facilitated further topographic *** Himalayan metamorphic studies should focus on extreme metamorphism and major collisional events,contact metamorphism and rare metal mineralization,metamorphic decarbonation and the carbon cycle in collisional belts.

关键词： continental collision crustal thickening mountain uplift critical taper wedge and channel flow P-T-t path Himalaya

Effect of exogenous additives on heavy metal passivation and nitrogen retention in pig manure composting

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 468-484页

作者： Ziqi wang Guotao SUN jiamin wang Gongshe YANG College of Animal Science and Technology Northwest A&F UniversityYangling 712100China College of Horticulture Northwest A&F UniversityYangling 712100China

The widespread use of feed additives in intensive and large-scale pig farming has resulted in high levels of heavy metals in pig *** long-term application of organic fertilizers containing high levels of heavy metals leads to the accumulation of heavy metals in the soil,which not only causes heavy metal pollution in the soil,and also affect food safety and endanger human *** is an economical and effective technical measures to achieve environmentally-sustainable treatment of pig manure and is a practical method to reduce the problem of heavy metals and to improve the resource value of pig *** composting process is accompanied by high temperatures and the production and emission of gases,and also lead to changes in the nitrogen content of the compost and provide opportunity for heavy metal passivation *** paper summarizes the forms and types of heavy metals present in pig manure and reviews the progress of research as well as the techniques and problems of in the composting process,and provides recommendations for research on heavy metal passivation and nitrogen retention in pig manure composting.

关键词： Additives composting heavy metals passivation nitrogen retention pig manure

A preliminary study of rare-metal mineralization in the Himalayan leucogranite belts, South Tibet

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Science China Earth Sciences 2017年第9期60卷 1655-1663页

作者： wang RuCheng WU FuYuan XIE Lei LIU XiaoChi wang jiamin YANG Lei LAI Wen LIU Chen State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing 210023 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The Himalayan leucogranite occurs as two extensive(>1000 km) E-W trending belts on the Tibetan Plateau with the unique features. The leucogranite comprised biotite granite, two-mica/muscovite granite, tourmaline granite and garnet granite, which have been identified in previous studies, as well as albite granite and granitic pegmatite that were identified in this investigation. Fifteen leucogranite plutons were studied and 12 were found to contain rare-metal bearing minerals such as beryl(the representative of Be mineralization), columbite-group minerals, tapiolite, pyrochlore-microlite, fergusonite, Nb-Ta rutile(the representative of Nb-Ta mineralization), and cassiterite(the representative of Sn mineralization) mainly based on the field trip,microscope observation and microprobe analysis. The preliminary result shows that the Himalayan leucogranite is commonly related to the rare-metal mineralization and warrants future investigation. Further exploration and intensive research work is important in determining the rare-metal resource potential of this area.

关键词： Leucogranite Beryl Columbite-group minerals Cassiterite Rare-metal mineralization Himalaya South Tibet

Deterioration of equivalent thermal conductivity of granite subjected to heating-cooling treatment

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第10期16卷 4229-4246页

作者： Mohua Bu Peng Zhang Pingye Guo jiamin wang Zhaolong Luan Xin Jin State Key Laboratory for Geo-Mechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Qilu Transportation Shandong UniversityJinan250001China Academy of Deep Earth Sciences Chinese Institute of Coal ScienceBeijing100013China China State Key Laboratory of Coal Mining and Clean Utilization China Coal Technology and Engineering GroupBeijing100013China

Understanding the thermal conductivity of granite is critical for many geological and deep engineering *** heated granite was subjected to air-,water-,and liquid nitrogen(LN2-)coolings in this *** transient hot-wire technique was used to determine the equivalent thermal conductivity(ETC)of the granite before and after *** deterioration mechanism of ETC is analyzed from the ***,the numerical model is used to quantitatively study the impact of cooling rate on the microcrack propagation and heat conduction characteristics of *** results show that the ETC of granite is not only related to the heating temperature,but also affected by the cooling *** ETC of granite decreases nonlinearly with increasing heating temperature.A faster cooling rate causes a greater decrease in ETC at the same heating *** higher the heating temperature,the stronger the influence of cooling rate on *** main explanation for the decrease in ETC of granite is the increase in porosity and microcrack density produced by the formation and propagation of pore structure and microcracks during heating and *** analysis displays that the damage of granite at the heating stage is induced by the difference in thermal expansion and elastic properties of mineral *** the cooling stage,the faster cooling rate causes a higher temperature gradient,which in turn produces greater thermal *** a result,it not only causes new cracks in the granite,but also aggravates the damage at the heating stage,which induces a further decrease in the heat conduction performance of granite,and this scenario is more obvious at higher temperatures.

关键词： Equivalent thermal conductivity(ETC) Granite Heating-cooling treatment Pore structure Microcrack Grain-based model

Endogenous peroxynitrite activated fluorescent probe for revealing anti-tuberculosis drug induced hepatotoxicity

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Chinese Chemical Letters 2022年第3期33卷 1584-1588页

作者： Nannan wang Han wang Jian Zhang Xin Ji Huihui Su Jinying Liu jiamin wang Weili Zhao Key Laboratory for Special Functional Materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng 475004China School of Pharmacy Institutes of Integrative MedicineFudan UniversityShanghai 201203China Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province Henan UniversityKaifeng 475004China

Py^(+)razinamide (PZA), isoniazid (INH) and rifampicin (RFP) are all commonly used anti-tuberculosis drugs in clinical practice, and long-term medication may cause severe liver damage and toxicity. The level of peroxynitrite (ONOO^(-)) generated in liver has long been regarded as a biomarker for the prediction and measurement of drug-induced liver injury (DILI). In this article, we constructed a BODIPY-based fluorescent probe (BDP-Py^(+)) that enabled quickly and sensitively detect and image ONOO^(-) in vivo. Utilizing this probe, we demonstrated the change of ONOO^(-) content in cells and mice model of DILI induced by acetaminophen (APAP), and for the first time revealed the mechanism of liver injury induced by antituberculosis drug PZA. Moreover, BDP-Py^(+) could be applied to screen out and evaluate the hepatotoxicity of different anti-tuberculosis drugs. Comparing with the existing serum enzymes detection and H&E staining, the probe could achieve early diagnosis of DILI before solid lesions in liver via monitoring the up-regulation of ONOO^(-) levels. Collectively, this work will promote the understanding of the pathogenesis of anti-tuberculosis drug induced liver injury (ATB-DILI), and provide a powerful tool for the early diagnosis and treatment of DILI.

关键词： Anti-tuberculosis drug induced liver injury Peroxynitrite Fluorescent probe Drug-induced liver injury Bioimaging

NMR diffusion analysis of catalytic conversion mixtures from lignocellulose biomass using PSYCHE-iDOSY

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Green Energy & Environment 2023年第5期8卷 1409-1416页

作者： Qi Zhao Christian Marcus Pedersen jiamin wang Rui Liu Yuanli Zhang Xiuyin Yan Zhenzhou Zhang Xianglin Hou Yingxiong wang Shanxi Engineering Research Center of Biorefinery Institute of Coal ChemistryChinese Academy of Sciences27 South Taoyuan RoadTaiyuan030001China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Department of Chemistry University of CopenhagenUniversitetsparken 5DK-2100CopenhagenDenmark School of Chemical Engineering Zhengzhou University Zhengzhou450001China Shanxi Inspection and Testing Center 106 Changzhi RoadTaiyuan030012China

The component analysis and structure characterization of complex mixtures of biomass conversion remain a challenging ***,developing effective and easy to use techniques is ***-ordered NMR spectroscopy(DOSY)is a non-selective and non-invasive method capable of achieving pseudo-separation and structure assignments of individual compounds from biomass mixtures by providing diffusion coefficients(D)of the ***,the conventional 1H DOSY NMR is limited by crowded resonances when analyzing complex mixtures containing similar chemical structure resulting in similar *** we describe the application of an advanced diffusion NMR method,Pure Shift Yielded by CHirp Excitation DOSY(PSYCHE-iDOSY),which can record high-resolution signal diffusion spectra efficiently separating compounds in model and genuine mixture samples from cellulose,hemicellulose and *** sets of isomers(D-glucose/D-fructose/D-mannose and 1,2-/1,5-pentadiol),homologous compounds(ethylene glycol and 1,2-propylene glycol),model compounds of lignin,and a genuine reaction system(furfuryl alcohol hydrogenolysis with ring opening)were successfully separated in the diffusion *** results show that the ultrahigh-resolution DOSY technique is capable of detecting and pseudo-separating the mixture components of C_(5)/C_(6) sugar conversion products and its derivative hydrogenation/hydrogenolysis from lignocellulose biomass.

关键词： Diffusion NMR Pure shift spectroscopy PSYCHE-iDOSY Mixture analysis Biomass