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On the Design and Optimization of a Clean and Efficient Combustion Mode for internal Combustion Engines through a Computer NSGA-Ⅱ Algorithm

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Fluid Dynamics & Materials Processing 2020年第5期16卷 1019-1029页

作者： Xiaobin shu Miaomiao ren Luohe Vocational College of Food Luohe462300China

in order to address typical problems due to the huge demand of oil for consumption in traditional internal combustion engines,a new more efficient combustion mode is proposed and studied in the framework of Computational Fluid Dynamics(CFD).Moreover,a Non-dominated Sorting Genetic Algorithm(NSGA-Ⅱ)is applied to optimize the related parameters,namely,the engine methanol ratio,the fuel injection time,the initial temperature,the Exhaust Gas Re-Circulation(EGR)rate,and the initial *** so-called Conventional Diesel Combustion(CDC),Homogeneous Charge Compression ignition(HCCi)and the Reactivity Controlled Compression ignition(RCCi)combustion modes are *** results show that RCCi has a higher methanol ratio and an earlier injection timing with moderate EGR rate and higher initial *** initial temperature increases as the methanol ratio *** comparison,CDC has the lowest hydrocarbon and CO emissions and the highest combustion *** different crankshaft rotation angles corresponding to 50%of the combustion amount(CA50),the combustion temperature and boundary layer temperature of HCCi change significantly,while those of RCCi undergo limited *** the same CA50,the exergy losses of HCCi and RCCi are lower than that of the *** the basis of these findings,it can be concluded that the methanol/diesel RCCi engine can be used to obtain a clean and efficient combustion process,which should be regarded as a promising combustion mode.

关键词： Computer-optimized NSGA-Ⅱalgorithm novel clean and efficient combustion mode thermodynamics combustion engine methanol

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秸秆基高强度透明纤维素薄膜

高分子学报 2024年第8期55卷 1009-1020页

作者：张书玉郭建荣贺军辉任世学东北林业大学材料科学与工程学院哈尔滨150040 中国科学院理化技术研究所北京100190

以农业废弃产物秸秆皮作为原料,通过简单热压的方法提纯纤维素,制备了不同厚度的微纤薄膜(SCfilms),将环氧树脂加压铸入微纤薄膜获得了纤维素-环氧树脂复合薄膜(SC-Epfilms).采用扫描电子显微镜、傅里叶变换红外光谱仪、紫外-可见分光... 详细信息

以农业废弃产物秸秆皮作为原料,通过简单热压的方法提纯纤维素,制备了不同厚度的微纤薄膜(SCfilms),将环氧树脂加压铸入微纤薄膜获得了纤维素-环氧树脂复合薄膜(SC-Epfilms).采用扫描电子显微镜、傅里叶变换红外光谱仪、紫外-可见分光光度计对SC与SC-Ep薄膜分别进行表征,并对其力学性能、防水性、热稳定性、有机溶剂稳定性及阻隔性能进行测试.结果表明,最佳复合薄膜(SC_(4)-Ep1)呈现了优异的透光性(最高透过率可达87%)、高力学强度(拉伸应力可达83.4 MPa,杨氏模量为5.41 GPa),远高于文献中以及市场上同类型的塑料薄膜材料.此外,从SC_(4)薄膜到SC_(4)-Ep_(1)薄膜,接触角提高至98.9°,水蒸气透过率显著降低了75.12%,表现出优异的阻隔性能.SC_(4)-Ep_(1)复合薄膜在水中以及多种有机溶剂中表现出极强的稳定性.本工作为制备复合生物基薄膜以及生物基塑料产品提供了新的思路.

关键词：纤维素环氧树脂透明力学性能生物质复合材料

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A Novel Approach for the Numerical Simulation of Fluid-Structure interaction Problems in the Presence of Debris

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Fluid Dynamics & Materials Processing 2020年第5期16卷 979-991页

作者： Miaomiao ren Xiaobin shu Luohe Vocational College of Food Luohe462300China

A novel algorithm is proposed for the simulation of fluid-structure interaction *** particular,much attention is paid to natural phenomena such as debris *** fluid part(debris flow fluid)is simulated in the framework of the smoothed particle hydrodynamics(SPH)approach,while the solid part(downstream obstacles)is treated using the finite element method(FEM).Fluid-structure coupling is implemented through dynamic boundary *** particular,the software“TensorFlow”and an algorithm based on Python are combined to conduct the required *** simulation results show that the dynamics of viscous and non-viscous debris flows can be extremely different when there are obstacles in the downstream *** implemented SPH-FEM coupling method can simulate the fluid-structure coupling problem with a reasonable approximation.

关键词： Fluid-structure coupling SPH FEM TensorFlow python dynamic boundary conditions

急性敌敌畏中毒患者休克的临床特征及危险因素分析

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中华急诊医学杂志 2024年第3期33卷 291-296页

作者：葛洪霞任珍杨兴龙李姝马青变北京大学第三医院急诊科北京100191 解放军总医院第五医学中心北京100039

目的本研究旨在探讨急性敌敌畏中毒合并休克患者的临床特征,分析其危险因素。方法回顾分析2019年1月至2020年9月间北京大学第三医院和解放军总医院第五医学中心收治的急性敌敌畏中毒患者的临床资料,收集人口学资料、中毒情况、临床表现... 详细信息

目的本研究旨在探讨急性敌敌畏中毒合并休克患者的临床特征,分析其危险因素。方法回顾分析2019年1月至2020年9月间北京大学第三医院和解放军总医院第五医学中心收治的急性敌敌畏中毒患者的临床资料,收集人口学资料、中毒情况、临床表现、化验检查、治疗措施及临床结局等,建立临床数据库。将患者分为两组:休克组和非休克组,比较两组间临床资料,分析急性敌敌畏中毒发生休克的临床特征和预后情况,采用Logistic回归分析急性敌敌畏中毒患者发生休克的危险因素。结果本研究共纳入符合标准的急性敌敌畏中毒患者134例,入院24 h内的休克发生率为39.6%(53/134),11例(8.21%)患者院内死亡,休克组患者的院内病死率高于非休克组(20.8%vs.0.0%,PiCU时间、有创呼吸机使用时间更长。二元Logistic回归分析显示,有括约肌松弛表现(OR=10.888,95%Ci:1.677~70.684,P=0.012)是急性敌敌畏中毒患者合并休克的独立危险因素,使用胆碱酯酶复能剂(OR=0.246,95%Ci:0.072~0.846,P=0.026)是急性敌敌畏中毒患者合并休克的保护因素。结论急性敌敌畏中毒患者休克发病率较高且影响临床预后,有括约肌松弛表现、未使用胆碱酯酶复能剂是急性敌敌畏中毒患者合并休克的独立危险因素。

关键词：有机磷农药急性敌敌畏中毒休克危险因素预后

异伍兹烷衍生物高温热分解规律分子动力学模拟

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含能材料 2024年第7期32卷 711-725页

作者：甘强张文博王亚军梁琳任姝李根何佳峻冯长根北京理工大学爆炸科学与安全防护全国重点实验室北京100081

异伍兹烷衍生物是当前最具潜力的笼形含能化合物之一,为了系统研究异伍兹烷衍生物的高温热分解规律,明确其爆轰机理,研究采用ReaxFF-lg反应性力场和分子动力学方法,对3种典型异伍兹烷衍生物ε-六硝基六氮杂异伍兹烷(ε-CL-20)、4,10-二... 详细信息

异伍兹烷衍生物是当前最具潜力的笼形含能化合物之一,为了系统研究异伍兹烷衍生物的高温热分解规律,明确其爆轰机理,研究采用ReaxFF-lg反应性力场和分子动力学方法,对3种典型异伍兹烷衍生物ε-六硝基六氮杂异伍兹烷(ε-CL-20)、4,10-二硝基-2,6,8,12-四氧杂-4,10-二氮杂四环十二烷(TEX)和4,10-二叠氮甲基-2,6,8,12-四硝基六氮杂异伍兹烷(BATNiW)进行高温(1500~3500 K)热分解研究。结果表明,脱硝基和开环是3种衍生物的主要初始反应,其中开环反应集中在五元环C—N键或C—O键。不同温度下热分解终产物中CO_(2)和H_(2)含量差异较大,3000 K以上N_(2)含量接近。3种衍生物中,BATNiW热分解生成N_(2)速度最快、产量最高;TEX热分解易生成团簇,生成特征产物乙二醛。3种衍生物热分解活化能排序为TEX>BATNiW>ε-CL-20,说明TEX稳定性最好。研究初步揭示了3种异伍兹烷衍生物分子结构与热分解规律的内在联系。

关键词：异伍兹烷衍生物六硝基六氮杂异伍兹烷高温热分解分子动力学方法 ReaxFF-lg反应性力场

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On the diffuse soft X-ray emission from the nuclear region of M51

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Research in Astronomy and Astrophysics 2015年第12期15卷 2164-2172页

作者： Ji-ren Liu shu-De Mao National Astronomical Observatories Chinese Academy of Sciences Physics Department and Tsinghua Center for Astrophysics Tsinghua University Jodrell Bank Centre for Astrophysics University of Manchester

We present an analysis of the diffuse soft X-ray emission from the nuclear region of M51 combining both XMM-Newton RGS and Chandra data. Most of the RGS spectrum of M51 can be fitted with a thermal model with a temperature of 0.5 keV except for the O vii triplet, which is forbidden-line dominated. The Fe L-shell lines peak around the southern cloud, where the O viii and N vn Lya lines also peak. in contrast, the peak of the O vii forbidden line is about 10＂ offset from that of the other lines, indicating that it is from a spatially distinct component. The spatial distribution of the O vii triplet mapped by the Chandra data shows that most of the O vii triplet flux is located at faint regions near edges, instead of the southern cloud where other lines peak. This distribution of the O vii triplet is inconsistent with the photoionization model. Other mechanisms that could produce the anomalous O vii triplet, including a recombining plasma and charge exchange X-ray emission, are discussed.

关键词： atomic processes -- plasmas -- iSM: jets and outflows -- galaxies:Seyfert -- galaxies: individual: M51 (NGC 5194) -- X-rays: iSM

Circulating tumor DNA and its role in detection, prognosis and therapeutics of hepatocellular carcinoma

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Chinese Journal of Cancer Research 2024年第2期36卷 195-214页

作者： Sana Rashid Yingchuan Sun Umair Ali Khan Saddozai Sikandar Hayyat Muhammad Usman Munir Muhammad Usman Akbar Muhammad Babar Khawar Zhiguang ren Xinying Ji Malik ihsan Ullah Khan institute of Molecular Biology and Biotechnology University of LahoreLahore 54590Pakistan Department of internal Oncology(Section Ⅰ) Xuchang Municipal Central HospitalXuchang 461000China institute of Translational Medicine Medical CollegeYangzhou UniversityYangzhou 225001China Australian institute for Bioengineering&Nanotechnology the University of QueenslandBrisbane 4072Australia Gomal Center of Biochemistry and Biotechnology Gomal UniversityDera Ismail Khan 29111Pakistan Applied Molecular Biology and Biomedicine Lab Department of ZoologyUniversity of NarowalNarowal Punjab 51600Pakistan Kaifeng Municipal Key Laboratory for infection and Biosafety Henan International Joint Laboratory of Nuclear Protein RegulationSchool of Basic Medical SciencesHenan UniversityKaifeng 475004China Faculty of Basic Medical Subjects Shu-Qing Medical College of ZhengzhouZhengzhou 450064China Department of Medicine Huaxian County People's HospitalHuaxian 456400China

Hepatocellular carcinoma(HCC) is considered the fifth most prevalent cancer among all types of cancers and has the third most morbidity value. it has the most frequent duplication time and a high recurrence rate. Recently, the most unique technique used is liquid biopsies, which carry many markers;the most prominent is circulating tumor DNA(ctDNA). Varied methods are used to investigate ctDNA, including various forms of polymerase chain reaction(PCR) [emulsion PCR(ePCR), digital PCR(dPCR), and bead, emulsion, amplification, magnetic(BEAMing) PCR]. Hence ctDNA is being recognized as a potential biomarker that permits early cancer detection,treatment monitoring, and predictive data on tumor burden are subjective to therapy or surgery. Numerous ctDNA biomarkers have been investigated based on their alterations such as 1) single nucleotide variations(either insertion or deletion of a nucleotide) markers including TP53, KRAS, and CCND1;2) copy number variations which include markers such as CDK6, EFGR, MYC and BRAF;3) DNA methylation(RASSF1A, SEPT9, KMT2C and CCNA2);4) homozygous mutation includes ctDNA markers as CDKN2A, AXiN1;and 5) gain or loss of function of the genes, particularly for HCC. Various researchers have conducted many studies and gotten fruitful ***, there are some drawbacks to ctDNA namely low quantity, fragment heterogeneity, less stability, limited mutant copies and standards, and differential sensitivity. However, plenty of investigations demonstrate ctDNA's significance as a polyvalent biomarker for cancer and can be viewed as a future diagnostic, prognostic and therapeutic agent. This article overviews many conditions in genetic changes linked to the onset and development of HCC, such as dysregulated signaling pathways, somatic mutations, single-nucleotide polymorphisms, and genomic instability. Additionally, efforts are also made to develop treatments for HCC that are molecularly targeted and to unravel some of the genetic pathways that f

关键词： Hepatocellular carcinoma circulating tumor DNA biomarkers single nucleotide variations diagnosis prognosis

identification of marker genes associated with N6-methyladenosine and autophagy in ulcerative colitis

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World Journal of Clinical Cases 2024年第10期12卷 1750-1765页

作者： Xiao-Yan Liu Dan Qiao Ya-Li Zhang Zi-Xuan Liu You-Lan Chen ren-Ye Que Hong-Yan Cao Yan-Cheng Dai Department of Gastroenterology Shanghai Traditional Chinese Medicine-Integrated HospitalShanghai University of Traditional Chinese MedicineShanghai 200082China institute of Digestive Diseases Long Hua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200032China Department of Gastroenterology Shu Guang HospitalShanghai University of Traditional Chinese MedicineShanghai 201203China

BACKGROUND Both N6-methyladenosine(m6A)methylation and autophagy are considered relevant to the pathogenesis of ulcerative colitis(UC).However,a systematic exploration of the role of the com-bination of m6A methylation and autophagy in UC remains to be *** To elucidate the autophagy-related genes of m6A with a diagnostic value for *** The correlation between m6A-related genes and autophagy-related genes(ARGs)was ***,gene set enrichment analysis(GSEA)was performed on the characteristic ***,the expression levels of four characteristic genes were verified in dextran sulfate sodium(DSS)-induced colitis in *** GSEA indicated that BAG3,P4HB and TP53iNP2 were involved in the inflammatory response and TNF-αsignalling via nuclear factor ***,polymerase chain reaction results showed significantly higher mRNA levels of BAG3 and P4HB and lower mRNA levels of FMR1 and TP53iNP2 in the DSS group compared to the control *** This study identified four m6A-ARGs that predict the occurrence of UC,thus providing a scientific reference for further studies on the pathogenesis of UC.

关键词： Ulcerative colitis m6A Autophagy Characteristic genes immune infiltration

Undesorbable residual gas in coal seams and its influence on gas drainage

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international Journal of Mining Science and Technology 2017年第5期27卷 763-769页

作者： Wang Gongda ren Ting Zhang Lang shu Longyong Mine Safety Technology Branch China Coal Research Institute School of Civil Mining and Environmental EngineeringUniversity of Wollongong

The definition of ‘‘residual gas" can be found in different scenarios, such as the ‘‘fast" and ‘‘slow" desorption methods of measuring gas content and the sorption hysteresis test and gas management of coal mines, however, its meaning varies a lot in different contexts. The main aim of this paper is to discuss the existence of truly undesorbable residual gas in coal seam conditions and its impacts on sorption model and gas drainage efficiency. We believe the undesorbable residual gas does exist due to the observation of the extended slow desorption test and the sorption hysteresis test. The origin of undesorbable residual gas may be because of the inaccessible(closed or semi-closed) pores. Some gas molecules produced during coalification are stored in these inaccessible pores, since the coal is relatively intact in the coal seam condition, these gas molecules cannot escape during natural desorption and then create the undesorbable residual gas. Based on the existing adsorption models, we propose the improved desorption versions by taking into consideration the role of residual gas. By numerically simulating a gas drainage case, the gas contents after different drainage times are studied to understand the influence of residual gas content on gas drainage. The results indicate that the influence starts to be obvious even when the total gas content is at a high level, and the impact becomes more and more apparent with increasing drainage time. Our study shows that the existence of residual gas will impede the gas drainage and the total amount of recoverable coal seam methane may be less than expected.

关键词： Residual gas inaccessible pores Desorption model Gas drainage