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A comparative single-pulse shock tube experiment and kinetic modeling study on pyrolysis of cyclohexane,methylcyclohexane and ethylcyclohexane

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Defence Technology（防务技术） 2023年第2期20卷 137-148页

作者： Jin-hu liang Shu-tong Cao Fei li Xiao-Liang Li Rui-ning He Xin Bai Quan-De Wang Yang li School of Environmental and Safety Engineering North University of ChinaTaiyuan030051People's Republic of China Science and Technology on Combustion Internal Flow and Thermostructure LaboratorySchool of AstronauticsNorthwestern Polytechnical UniversityXi'an 710072People's Republic of China Low Carbon Energy Institute and School of Chemical Engineering China University of Mining and TechnologyXuzhou 221008People's Republic of China

The pyrolysis of cyclohexane,methylcyclohexane,and ethylcyclohexane have been studied behind reflected shock waves at pressures of 5 and10 bar and at temperatures of 930-1550 K for 0.05%fuel diluted by Argon.A single-pulse shock tube(SPST)is used to perform the pyrolysis experiments at reaction times varying from 1.65 to 1.74 ms.Major products are obtained and quantified using gas chromatography analysis.A flame ionization detector and a thermal conductivity detector are used for species identification and quantification.Kinetic modeling has been performed using several detailed and lumped chemical kinetic mechanisms.Differences in modeling results among the kinetic models are described.Reaction path analysis and sensitivity analysis are performed to determine the important reactions controlling fuel pyrolysis and their influence on the predicted concentrations of reactant and product species profiles.The present work provides new fundamental knowledge in understating pyrolysis characteristics of cyclohexane compounds and additional data set for detailed kinetic mechanism development.

关键词： Cyclohexane Alkylated cyclohexane Single-pulse shock tube Pyrolysis Kinetic modeling

Uniqueness on Difference Operators of Meromorphic Functions of Infinite Order

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Acta Mathematica Sinica,English Series 2024年第2期40卷 511-527页

作者： Hui li Ming liang FANG xiao YAO School of Science China University of Mining and TechnologyBeijing 100083P.R.China Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100190P.R.China School of Sciences Hangzhou Dianzi UniversityHangzhou 310012P.R.China School of Mathematical sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new method.It is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of Jank-Mues-Volkmann.Our method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding vectors.This makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the functions.Furthermore,the idea in this paper can also be applied to the case for several variables.

关键词： Uniqueness meromorphic functions difference operators infinite order

One-step green method to prepare progressive burning gun propellant through gradient denitration strategy

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Defence Technology（防务技术） 2023年第4期22卷 135-143页

作者： Shi-ying li Yu li Ya-jun Ding Hao liang Zhong-liang xiao School of Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Special Energy Materials(Nanjing University of Science and Technology) Ministry of EducationNanjing210094China

Gradiently denitrated gun propellant(GDGP)prepared by a“gradient denitration”strategy is obviously superior in progressive burning performance to the traditional deterred gun propellant.Currently,the preparation of GDGP employed a tedious two-step method involving organic solvents,which hinders the large-scale preparation of GDGP.In this paper,GDGP was successfully prepared via a novelty and environmentally friendly one-step method.The obtained samples were characterized by FT-IR,Raman,SEM and XPS.The results showed that the content of nitrate groups gradiently increased from the surface to the core in the surface layer of GDGP and the surface layer of GDGP exhibited a higher compaction than that of raw gun propellant,with a well-preserved nitrocellulose structure.The denitration process enabled the propellant surface with regressive energy density and good progressive burning performance,as confirmed by oxygen bomb and closed bomb test.At the same time,the effects of different solvents on the component loss of propellant were compared.The result showed that water caused the least component loss.Finally,the stability of GDGP was confirmed by methyl-violet test.This work not only provided environmentally friendly,simple and economic preparation of GDGP,but also confirmed the stability of GDGP prepared by this method.

关键词： Gradiently denitrated gun propellant One-step green method Denitration Progressive burning Stability

Loss-of-function CFTR p.G970D missense mutation might cause congenital bilateral absence of the vas deferens and be associated with impaired spermatogenesis

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Asian Journal of Andrology 2023年第1期25卷 58-65页

作者： Jian-Wen Hou Xiao-Liang Li li Wang Cong-ling Dai Na li xiao-Hui Jiang Yue-Qiu Tan Er-Po Tian Qin-Tong li Wen-Ming Xu Department of Obstetrics/Gynecology Key Laboratory of ObstetricGynecologic and Pediatric Diseases and Birth Defects of Ministry of EducationWest China Second University HospitalSichuan UniversityChengdu 610041China Reproductive Medical Center Chengdu Xi'nan Gynecology HospitalChengdu 610041China Reproductive Medical Center of West China Second University Hospital Sichuan UniversityChengdu 610041China Reproductive Medical Center Gansu Provincial Maternal and Child-Care HospitalLanzhou 730050China Institute of Reproductive and Stem Cell Engineering School of Basic Medical ScienceCentral South UniversityChangsha 410000China Reproductive and Genetic Hospital of CITIC-Xiangya Changsha 410000China Institute of Pediatrics Guangzhou Women and Children's Medical CenterGuangzhou Medical UniversityGuangzhou 510623China Human Sperm Bank West China Second University HospitalSichuan UniversityChengdu 610041China Clinical Research Center for Reproduction and Genetics in Hunan Province Changsha 410000China Department of Obstetrics Gynecology and PediatricsWest China Second University HospitalKey Laboratory of Birth Defects and Related Diseases of Women and ChildrenMinistry of EducationSichuan UniversityChengdu 610041China

Congenital bilateral absence of the vas deferens(CBAVD)is observed in 1%–2%of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator(CFTR)mutations.CFTR is one of the most well-known genes related to male fertility.The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia(NOA).CFTR mutations are highly polymorphic and have established ethnic specificity.Compared with F508Del in Caucasians,the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis.However,whether p.G970D participates in male infertility remains unknown.Herein,a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA.Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation(4.1%,5/122),excluding polymorphic sites.Furthermore,we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients.The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells.In spermatocyte GC-2(spd)ts(GC2)Cftr p.G965D cells,RNA splicing variants were detected and CFTR expression decreased,which may contribute to the phenotypes associated with impaired spermatogenesis.Thus,this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.

关键词： azoospermia congenital bilateral absence of the vas deferens CFTR mutation male infertility spermatogenesis

ICS-SVM:A user retweet prediction method for hot topics based on improved SVM

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Digital Communications and Networks 2022年第2期8卷 186-193页

作者： Tianji Dai Yunpeng xiao Xia liang Qian li Tun li School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

In social networks,many complex factors affect the prediction of user forwarding behavior.This paper proposes an improved SVM prediction method for user forwarding behavior of hot topics to improve prediction accuracy.Firstly,we consider that the improved Cuckoo Search algorithm can select the optimal penalty parameters and kernel function parameters to optimize the SVM and thus predict the user's forwarding behavior.Secondly,this paper considers the factors that affect the user forwarding behavior comprehensively from the user's own factors and external factors.Finally,based on the characteristics of the user's forwarding behavior changing over time,the time-slicing method is used to predict the trend of hot topics.Experiments show that the method can accurately predict the user's forwarding behavior and can sense the trend of hot topics.

关键词： Cuckoo search algorithm Support vector machine Hot topic User behavior prediction

Causal gene identification and desirable trait recreation in goldfish

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Science China(life Sciences) 2022年第12期65卷 2341-2353页

作者： Peng Yu Yang Wang Zhi li Hui Jin liang-liang li xiao Han Zhong-Wei Wang xiao-li Yang Xi-Yin li xiao-Juan Zhang li Zhou Jian-Fang Gui State Key Laboratory of Freshwater Ecology and Biotechnology Hubei Hongshan LaboratoryThe Innovation Academy of Seed DesignInstitute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China

Goldfish(Carassius auratus) have long fascinated evolutionary biologists and geneticists because of their diverse morphological and color variations.Recent genome-wide association studies have provided a clue to uncover genomic basis underlying these phenotypic variations,but the causality between phenotypic and genotypic variations have not yet been confirmed.Here,we edited proposed candidate genes to recreate phenotypic traits and developed a rapid biotechnology approach which combines gene editing with high-efficiency breeding,artificial gynogenesis,and temperature-induced sex reversal to establish homozygous mutants within two generations(approximately eight months).We first verified that low-density lipoprotein receptorrelated protein 2B(lrp2a B) is the causal gene for the dragon-eye variation and recreated the dragon-eye phenotype in side-view Pleated-skirt lion-head goldfish.Subsequently,we demonstrated that the albino phenotype was determined by both homeologs of oculocutaneous albinism type II(oca2),which has subfunctionalized to differentially govern melanogenesis in the goldfish body surface and pupils.Overall,we determined two causal genes for dragon-eye and albino phenotypes,and created four stable homozygous strains and more appealing goldfish with desirable traits.The developed biotechnology approach facilitates precise genetic breeding,which will accelerate re-domestication and recreation of phenotypically desirable goldfish.

关键词： goldfish precise molecular design breeding re-domestication gene editing ornamental traits dragon-eye albino

3D visualization of hydraulic fractures using micro-seismic monitoring:Methodology and application

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Petroleum 2022年第1期8卷 92-101页

作者： Chenghua Ou Chenggang liang Zhaoliang li li Luo xiao Yang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China Petroleum Engineering School Southwest Petroleum UniversityChengdu610500China Jiqing Operation Area of PetroChina Xinjiang Oilfield Branch Fukang831511China Exploration and Development Research Institute of PetroChina Qinghai Oilfield Branch Dunhuang736200China Southwest Branch of China Petroleum Group Logging Co. Ltd.Chongqing400021China Southwest Research Institute of Dongfang Geophysical Exploration Co. Ltd.Chengdu610051China

In this paper,a new 3D visualization technical method was developed for hydraulic fractures using micro-seismic monitoring.This technical method consists of four steps:i.interpret the geologic hydraulic fracture model based on seismic source location data from micro-seismic monitoring;ii.develop a hydraulic fracture indication model,relying on the 3D spatial freeze-frame of micro-seismic monitoring sources from hydraulic fracturing;iii.construct a hydraulic fracture density model using the intensity from the micro-seismic monitoring;and iv.implement a 3D visualization of the hydraulic fractures,relying on the spatial constraints of the density model,the hydraulic fracture indication model,and the properties of the hydraulic fractures.This proposed technical method was used to produce 3D visualizations of the hydraulic fractures in well X in the Jiao reservoir,China,and the 3D visualizations of the distribution,development,extent and cutting relationships of hydraulic fractures were successfully realized.The results show that this technical method can be used as a practical and reliable approach to characterize hydraulic fractures.

关键词： 3D visualization Micro-seismic monitoring Hydraulic fracture Jiao reservoir Reservoir modelling

X-linked osteogenesis imperfecta accompanied by patent ductus arteriosus:a case with a novel splice variant in PLS3

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World Journal of Pediatrics 2022年第7期18卷 515-519页

作者： Chuang Qiu Qi-Wei li Lu Zhang Xiao-Liang Liu Department of Orthopaedics Shengjing Hospital of China Medical UniversityShenyangChina Department of Pediatric Orthopaedics Shengjing Hospital of China Medical UniversityShenyangChina Department of Clinical Genetics Shengjing Hospital of China Medical UniversityNo.36 Sanhao StreetShenyang 110004China

Osteogenesis imperfecta(OI),also known as brittle bone disease,is characterized by low bone mass and bone fragil-ity,which varies in severity from asymptomatic to perina-tal lethality[1].Most patients with OI experience recur-rent bone fractures with or without short stature,facial dysmorphism,and skeletal deformities.The accompany-ing extraskeletal manifestations include blue sclerae,joint laxity,dentinogenesis imperfecta,and hearing impairment.Approximately 85-90%of patients with OI have mutations in either COL1A1 or COL1A2,which elicit defects in typeⅠcollagen.Recently,an X-linked subtype of OI that is unre-lated to collagen was identified and was attributed to muta-tions in the plastin 3 gene(PLS3)[2].

关键词： skeletal imperfect facial

Verification and validation of detonation modeling

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Defence Technology（防务技术） 2019年第3期15卷 398-408页

作者： xiao liang Rui-li Wang Institute of Applied Physics and Computational Mathematics Beijing 100094 China College of Mathematics and Information Science Shandong University of Science and Technology Qingdao 266590 China

The mathematical model used to describe the detonation multi-physics phenomenon is usually given by highly coupled nonlinear partial differential equations. Numerical simulation and the computer aided engineering (CAE) technique has become the third pillar of detonation research, along with theory and experiment, due to the detonation phenomenon is difficult to explain by the theoretical analysis, and the cost required to accredit the reliability of detonation products is very high, even some physical experiments of detonation are impossible. The numerical simulation technique can solve these complex problems in the real situation repeatedly and reduce the design cost and time stunningly. But the reliability of numerical simulation software and the serviceability of the computational result seriously hinders the extension, application and the self-restoration of the simulation software, restricts its independently innovational ability. This article deals with the physical modeling, numerical simulation, and software development of detonation in a unified way. Verification and validation and uncertainty quantification (V&V&UQ) is an important approach in ensuring the credibility of the modeling and simulation of detonation. V&V of detonation is based on our independently developed detonation multiphysics software-LAD2D. We propose the verification method based on mathematical theory and program function as well as availability of its program execution. Validation is executed by comparing with the experiment data. At last, we propose the future prospect of numerical simulation software and the CAE technique, and we also pay attention to the research direction of V&V&UQ.

关键词： Verification and validation Detonation Equation of state Detonation diffraction Reaction rate law