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A NOtE ON tHE NEStEDNESS PROPERtY FOR ORDERED MEDIAN PROBLEMS IN tREE NEtWORKS

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Journal of Systems Science & Complexity 2013年第3期26卷 335-340页

作者： t.ng huajun Faculty of Management and Administration Macao University of Science and Technology

the nestedness property has become an increasingly important means for devising efficient algorithms for network location *** have been attempts to explore the nestedness property of network location problems with some special cases of the convex ordered median ***,there is little research on the nestedness property for those problems with the concave ordered median *** paper constructs a tree network t and shows that the nestedness property cannot hold for the concave ordered median problem,which fills a gap in the research on the nestedness ***,the authors pose an open problem on identifying the nestedness property for the continuous strategic ordered median problem.

关键词： Nestedness property ordered median problem tree network.

A kinetic model for a single step biodiesel production from a high free fatty acid (FFA) biodiesel feedstock over a solid heteropolyacid catalyst

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Green Energy & Environment 2019年第3期4卷 328-341页

作者： Aashish Gaurav Stéphane Dumas Chau t.Q.Mai Flora t.t.ng Department of Chemical Engineering University of Waterloo

Production of biodiesel from yellow grease(waste cooking oil and waste animal fats) is fast emerging as a promising alternative to address the twin challenges before the biodiesel industry today-fluctuation in prices of vegetable oil and the food versus fuel debate. Yellow grease has a high percentage of free fatty acids(FFA) and proves to be an unsuitable feedstock for biodiesel production from commercially viable alkalicatalyzed production systems due to saponification problems.'Green' methodologies based on heterogeneous solid acid catalyzed reactions have the potential to simultaneously promote esterification and transesterification reactions of yellow grease to produce biodiesel without soap formation and offer easy catalyst separation without generation of toxic streams. this paper presents kinetic studies for the conversion of model yellow grease feeds to biodiesel using a heteropolyacid supported on alumina(HSiW/Al2O3) using a batch autoclave. three model yellow grease feeds were prepared using canola oil with added FFA such as palmitic, oleic and linoleic acid. A pseudo homogeneous kinetic model for the parallel esterification and transesterification was developed. the rate constants and activation parameters for esterification and transesterification reactions for the model yellow grease feeds were determined. the rate constants for esterification are higher than the transesterification rate constants. the kinetic model was validated using the experimental biodiesel data obtained from processing a commercial yellow grease feed. the kinetic model could be used to design novel processes to convert various low-value waste oils, fats and non-food grade oils to sustainable biodiesel.

关键词： Yellow grease Canola oil Free fatty acids Heteropolyacid Kinetics for esterification and transesterification

A new green process for biodiesel production from waste oils via catalytic distillation using a solid acid catalyst-Modeling, economic and environmental analysis

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Green Energy & Environment 2016年第1期1卷 62-74页

作者： Aashish Gaurav Flora t.t.ng Garry L.Rempel Department of Chemical Engineering University of Waterloo

the challenges in the chemical processing industry today are environmental concerns, energy and capital costs. Catalytic distillation(CD) is a green reactor technology which combines a catalytic reaction and separation via distillation in the same distillation column. Utilization of CD in chemical process development could result in capital and energy savings, and the reduction of greenhouse gases. the efficacy of CD and the economic merits, in terms of energy and equipment savings, brought by CD for the production of biodiesel from waste oil such as yellow grease is quantified. Process flow sheets for industrial routes for an annual production of 10 million gallon AStM purity biodiesel in a conventional process(reactor followed by distillation) and CD configurations are modeled in Aspen Plus. Material and energy flows, as well as sized unit operation blocks, are used to conduct an economic assessment of each process. total capital investment, total operat.ng and utility costs are calculated for each process. the waste oil feedstock is yellow grease containing both triglyceride and free fatty acid. Both transesterification and esterification reactions are considered in the process simulations. Results show a significant advantage of CD compared to a conventional biodiesel processes due to the reduction of distillation columns, waste streams and greenhouse gas emissions. the significant savings in capital and energy costs together with the reduction of greenhouse gases demonstrate that process intensification via CD is a feasible and new green process for the biodiesel production from waste oils.

关键词： Yellow grease Catalytic distillation Aspen plus economic analyzer Process intensification

Winter soil CO_2 efflux in two contrast.ng forest ecosystems on the eastern tibetan Plateau, China

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Journal of Forestry Research 2015年第3期26卷 679-686页

作者： Zhenfeng Xu Feifei Zhou huajun Yin Qing Liu Institute of Forest & Ecology Sichuan Agricultural University Chengdu Institute of Biology Chinese Academy of Sciences

Significant CO2 fluxes from snow-covered soils occur in cold biomes. However, little is known about winter soil respiration on the eastern tibetan Plateau of China. We therefore measured winter soil CO2 fluxes and estimated annual soil respiration in two contrast.ng coniferous forest ecosystems （a Picea asperata plantation and a natural forest）. Mean winter soil CO2 effluxes were 1.08 μmol m-2 s-1 in the plantation and 1.16 μmol m-2 s-1 in the natural forest. these values are higher than most reported winter soil CO2 efflux values for temperate or boreal forest ecosystems. Winter soil respiration rates were similar for our two forest ecosystems but mean soil CO2 efflux over the growing sea- son was higher in the natural forest than in the plantation. the estimated winter and annual soil effluxes for the natural forest were 176.3 and 1070.3 g m-2, respectively, based on the relationship between soil respiration and soil temperature, which were 17.2 and 9.7 % greater than their counterparts in the plantation. the contributions of winter soil respiration toannual soil efflux were 15.4 % tor the plantation and 16.5R for the natural forest and were statistically similar. Our results indicate that winter soil CO2 efflux from frozen soils in the alpine coniferous forest ecosystems of the eastern tibetan Plateau was considerable and was an important component of annual soil respiration. Moreover, reforesta- tion （natural coniferous forests were deforested and refor- ested with P. asperata plantation） may reduce soil respiration by reducing soil carbon substrate availability and input.

关键词： Winter soil CO2 efflux Eastern tibetanPlateau Natural coniferous forest Picea asperataplantation

Oblique Wave Motion over Multiple Submerged Porous Bars near a Vertical Wall

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Journal of Ocean University of China 2017年第4期16卷 568-574页

作者： ZHAO Yang LIU Yong LI huajun CHAng Ant.ng Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100P.R.China

this study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eigenfunction expansions. A complex dispersion relation is adopted to describe the wave elevation and energy dissipation over submerged porous bars. In the analytical solution, no limitations on the bar number, bar size, and spacing between adjacent bars are set. the convergence of the analytical solution is satisfactory, and the correctness of the analytical solution is confirmed by an independently developed multi-domain BEM （boundary element method） solution. Numerical examples are presented to examine the reflection and transmission coefficients of porous bars, CR and Cv, respectively, for engineering applications. the calculation results show that when the sum of widths for all the porous bars is fixed, increasing the bar number can significantly improve the sheltering function of the bars. Increasing the bar height can cause more wave energy dissipation and lower CR and Cr. the spacing between adjacent bars and the spacing between the last bar and the vertical wall are the key parameters affect.ng CR and Ct. the proposed analytical method may be used to analyze the hydrodynamic performance of submerged porous bars in preliminary engineering designs.

关键词： multiple porous bars oblique wave vertical wall reflection coefficient transmission coefficient

Nondestructive acquisition of the micro-mechanical properties of high-speed-dry milled micro-thin walled structures based on surface traits

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Chinese Journal of Aeronautics 2021年第5期34卷 438-451页

作者： Da QU Wei ZHEng Bo WAng Bo WU huajun CAO Hao YI the State Key Laboratory of Mechanical transmissions Chongqing UniversityChongqing 400044China College of Mechanical Engineering Chongqing UniversityChongqing 400044China Aerospace Research Institute of Materials&Processing technology Beijing 100076China Centre for Precision Engineering Harbin Institute of TechnologyHarbin 150001China

Requirements for the service performance of aeronautic microelectronic components are increasingly ***,sever issues,that the acquisition of the service performance such as micro-mechanical properties is destructive,limit the subsequent application of the tested *** this issue,this paper proposes a nondestructive acquisition method of the micro-mechanical properties of the accelerometer micro-components,based on analyzing surface *** select qualified components without damage,we firstly developed a quasi-static microtensile tester and then established a combination prediction model of mechanical properties based on micro-milled surface *** model works due to the thin-walled structure,which makes the machined surface traits have significant influences on the mechanical properties such as Young’s modulus,yield strength,tensile strength,and elongation at *** roughness,surface structure,and surface anisotropy are extracted to comprehensively present surface traits from different *** improving the practicability of the model,the principal component analysis(PCA)is adopted to reduce high-dimensional traits explanatory variable space into two dimensions,and regression analysis models are comparative established in predict.ng the mechanical *** analysis and error analysis are carried out to show the prediction *** maximum prediction error is about 10.62%,but the significance levels in the t-test of the predicted Young’s modulus and yield strength are not ***,kernel support vector regression(SVR)is imported to improve the prediction ability of the combination prediction *** residuals analysis result shows that SVR is effective in enhancing the prediction ability of this model.

关键词： Dimension reduction High-speed dry micro-milling Mechanical property Nondestructive acquisition SVR

Identification and Characterization of a Novel Single Domain Antibody Against Ebola Virus

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Virologica Sinica 2021年第6期36卷 1600-1610页

作者： Rui Wang Haiwei Zhang Cheng Peng Jian Shi huajun Zhang Rui Gong CAS Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Ebola virus(EBOV) belongs to the Filoviridae family and causes severe illnesses such as hemorrhagic fever with a high mortality rate up to 90%. Now two antibody drugs termed Inmazeb and Ebanga have been approved for treat.ng EBOV infection. However, clinical studies have demonstrated that the mortality rate of the patients who received these two antibody drugs remains above 30%. therefore, novel therapeutics with better efficacy is still desired. the isolated human IgG1 constant domain 2(CH2 domain) has been proposed as a scaffold for the development of C-based single domain antibodies(C-sd Abs) as therapeutic candidates against viral infections and other diseases. Here, we screened and identified a novel C-sd Ab termed M24 that targets EBOV glycoprotein(GP) from a C-sd Ab phage display library. M24 neutralizes the pseudotype EBOV with IC;of 0.8 nmol/L(12 ng/mL) and has modest neutralizing activity against authentic *** determination, including molecular docking and site mutation analysis, discloses that M24 binds to the internal fusion loop(IFL) within GP2, a transmembrane subunit of GP. Interest.ngly, we found that the binding of M24 to GP at pH5.5 has dramatically decreased compared to the binding at pH 7.5, which may lead to weak efficacy in the neutralization of authentic EBOV. Since no sd Ab against EBOV infection has been reported to date, our results not only give a proof of concept that sd Abs could be utilized for the development of potential therapeutic candidates against EBOV infection, but also provide useful information for the discovery and improvement of anti-EBOV agents.

关键词： Ebola virus(EBOV) Constant domain 2(CH2 domain) C-based single domain antibody(C-sdAb) Neutralize Fusion loop

the impact of alpha-fetoprotein(AFP),child-turcotte-pugh(CtP)score and disease staging on the survival of hepatocellular carcinoma(HCC)patients:a retrospective cohort from single oncology center

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Oncology Research 2025年第1期33卷 149-160页

作者： NASSER MULLA YOUSEF KAtIB ASIM M.ALMUGHAMSI DUAA S.ALKHAYAt MOHAMED MOSAAD SAMIR t.ALFOtIH RAWAN ALAOFI Department of Internal Medicine Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Radiology Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Surgery Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Endemic and Infectious Diseases Suez Canal UniversityIsmailia41522Egypt King Salman bin Abdulaziz Medical City Madinah42311Saudi Arabia Prince Mohammed Bin Abdulaziz Hospital Madinah41511Saudi Arabia

Background:Hepatocellular carcinoma(HCC)is the most common cause of cancer-related death in Saudi *** study aimed to investigate the patterns of HCC and the effect of tNM staging,Alfa-fetoprotein(AFP),and Child-turcotte Pugh(CtP)on patients’overall survival(OS).Methods:A retrospective analysis was conducted on 43 HCC patients at a single oncology center in Saudi Arabia from 2015 to *** patients had to fulfill one of the following criteria:(a)a liver lesion reported as definitive HCC on dynamic imaging and/or(b)a biopsy-confirmed ***:the mean patient age of all HCC cases was 66.8 with a male-to-female ratio of 3.3:*** patients were stratified into two groups:viral HCC(n=22,51%)and non-viral HCC(n=21,49%).Among viral-HCC patients,55%were due to HBV and 45%due to *** was diagnosed in 79%of *** and sex did not significantly statistically differ in OS among viral and non-viral HCC patients(p-value>0.05).About 65%of patients had tumor size>5 cm during the diagnosis,with a significant statistical difference in OS(p-value=0.027).AFP was>400 ng/ml in 45%of the *** was a statistically significant difference in the OS in terms of AFP levels(p-value=0.021).A statistically significant difference was also observed between the CtP score and OS(p-value=0.02).CtP class B had the longest *** was the most common treatment provided to HCC patients followed by sorafenib *** was a significant statistical difference in OS among viral and non-viral HCC patients(p-value=0.008).Conclusions:the most common predictors for OS were the underlying cause of HCC,AFP,and tumor *** having non-viral etiology,a tumor size>5 cm,an AFP>400 ng/mL,and a CtP score class C were all negatively associated with OS.

关键词： Hepatocellular carcinoma Pattern Alpha-fetoprotein(AFP) Child-turcotte-pugh Progression free survival

Cyan-green-emitt.ng Ca_(3)Sc_(2)Si_(3)O_(12):Ce^(3+)transparent ceramics:A promising color converter for high-brightness laser light.ng

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Journal of Advanced Ceramics 2023年第9期12卷 1731-1741页

作者： huajun Wu Hao Wu Guo-Hui Pan Liangliang Zhang Zhendong Hao Jiahua Zhang State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

transparent phosphor ceramics have received increasing attention for high-brightness laser light.ng,but commercially available phosphor ceramics are currently mainly limited to yellow YAG:Ce and green LuAG:Ce garnets,leaving a“cyan cavity”which is an obstacle to realizing full-color *** new phosphor ceramics capable of filling the cavity is a ***,for the first time,cyan-green-emitt.ng Ca_(3)Sc_(2)Si_(3)O_(12):Ce^(3+)(CSS:Ce)transparent ceramics have been successfully developed by two-step sintering technique under *** as-prepared CSS:Ce ceramics present high relative density of 99.7%and optical transmittance of 71%in the cyan-green spectral *** exhibits an efficient band emission peaking at 504 nm(under 450 nm excitation)with internal/external quantum efficiency of 91%/62%.Furthermore,it has excellent thermal stability with a thermal quenching temperature(t_(0.5))of 838 K,approximately 100 K higher than that of LuAG:Ce ceramics(738 K).In addition,the CSS:Ce ceramics can withstand blue laser density of 45.6 W/mm^(2)and meanwhile generates cyan-green light with a forward luminous flux of 813 lm and forward luminous efficacy of 162 lm/*** CSS:Ce transparent ceramics exhibit excellent luminescence performance comparable to the commercial LuAG:Ce ceramics and could be a highly promising color converter for high-brightness laser light.ng.

关键词： transparent ceramics color converter laser light.ng garnet Ca_(3)Sc_(2)Si_(3)O_(12)(CSS)