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市政污水中吗啡来源辨析

环境科学 2024年第5期45卷 2748-2756页

作者：邵雪婷赵悦彤蒋冰裴伟李彦莹谭冬芹王德高大连海事大学环境科学与工程学院大连116026

采用分析市政污水方法可以辨别吗啡合法或非法使用情况.由于污水中吗啡来源复杂,区分不同来源的贡献是吗啡使用调查的关键问题.选择典型城市,在2022年10月至2023年3月期间采集61个代表性污水处理厂的262份进水样品,分析了包括吗啡、可... 详细信息

采用分析市政污水方法可以辨别吗啡合法或非法使用情况.由于污水中吗啡来源复杂,区分不同来源的贡献是吗啡使用调查的关键问题.选择典型城市,在2022年10月至2023年3月期间采集61个代表性污水处理厂的262份进水样品,分析了包括吗啡、可待因、蒂巴因、罂粟碱、那可丁和单乙酰吗啡在内的6种生物碱的浓度,同时结合罂粟壳中生物碱的含量,应用比值法和正定矩阵因子分解(PMF)模型对污水中的生物碱进行源解析.污水中共检出5种生物碱,但海洛因的代谢产物单乙酰吗啡未检出.其中,吗啡和可待因的浓度明显高于那可丁、罂粟碱和蒂巴因.通过构建两种比值,即可待因/(吗啡+可待因)和那可丁/(那可丁+可待因),能够很好地定性区别罂粟壳使用来源.PMF的结果表明,污水中吗啡主要来源于医用吗啡(44.9%)、罂粟壳药物(43.7%)和可待因(9.4%).污水中吗啡来源具有显著月份变化趋势.在新冠疫情和甲流暴发期间,含有罂粟壳和可待因药物使用为主要来源,而吗啡镇痛药物使用来源相对稳定.清单分析与PMF源解析的结果具有一致性,表明模型的可靠性,同时也表明该城市吗啡主要是合法来源,不存在滥用情况.

关键词：污水吗啡比值法正定矩阵因子分解(PMF)模型罂粟壳

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多层钢结构模块建筑筒体结构受力分析与仿真

计算机仿真 2024年第2期41卷 295-299页

作者：樊志红李雁英王玉艳山西应用科技学院建筑工程学院山西太原030062 山西大学电力与建筑学院山西太原030006

在地震荷载作用下,建筑物内部结构会出现不同程度形变,严重时甚至会有倒塌危险。因此,研究了多层钢结构模块建筑筒体结构的受力性能。利用薄壳理论得出筒体的挠度、转度、弯矩与剪力等参数,确定模型及其边界条件,利用ABAQUS、插值算法... 详细信息

在地震荷载作用下,建筑物内部结构会出现不同程度形变,严重时甚至会有倒塌危险。因此,研究了多层钢结构模块建筑筒体结构的受力性能。利用薄壳理论得出筒体的挠度、转度、弯矩与剪力等参数,确定模型及其边界条件,利用ABAQUS、插值算法选取恰当的有限元单元,采用整体式方法划分有限元单元,构建完成筒体结构有限元模型。当筒体结构与刚度分布均匀时,选用振型分解反应谱算法分析筒体结构受力性能,反之,则选用时程分析算法分析其受力性能。实验结果表明,在水平、垂直方向施加荷载时,筒体结构会经历弹性、弹塑性强化与塑性变化过程,在1100KN时筒体产生负刚度,且存在剪力滞后效应。

关键词：有限元多层钢结构模块建筑筒体结构刚度有限元单元

Explicit Forms of q-Deformed Lévy-Meixner Polynomials and Their Generating Functions

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Acta Mathematica Sinica,English Series 2008年第2期24卷 201-214页

作者： Zhi Yuan HUANG Pei yan li ying WU Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 P. R. China

The classical Levy-Meixner polynomials are distinguished through the special forms of their generating functions. In fact, they are completely determined by 4 parameters： c1, c2,γ and β. In this paper, for-1 〈q〈 1, we obtain a unified explicit form of q-deformed Levy-Meixner polynomials and their generating functions in term of c1, c2, γand β, which is shown to be a reasonable interpolation between classical case （q=1） and fermionic case （q=-1）.In particular, when q=0 it＇s also compatible with the free case.

关键词： q-deformation Levy-Meixner polynomials generating function free probability

On the Hosoya index of graphs

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Applied Mathematics(A Journal of Chinese Universities) 2010年第2期25卷 155-161页

作者： WANG Bo YE Cheng-fu yan li-ying Department of Mathematics Qinghai Normal University Xining 810008 China Qinghai Communications Technical College Xining 810003 China.

Let G be a （molecular） graph. The Hosoya index Z（G） of G is defined as the number of subsets of the edge set E（G） in which no two edges are adjacent in G, i.e., Z（G） is the total number of matchings of G. In this paper, we determine all the connected graphs G with n ＋ 1 ≤ Z（G） ≤5n - 17 for n ≥ 19. As a byproduct, the graphs of n vertices with Hosoya index from the second smallest value to the twenty first smallest value are obtained for n ≥ 19.

关键词： Graph Hosoya index matching

无机化学“多元互动”课堂教学模式的建构与成效——以贵州师范学院化学专业为例

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贵州师范学院学报 2024年第9期40卷 19-25页

作者：文君武汉清李艳莹贵州师范学院化学与材料学院贵州贵阳550018

针对无机化学教学中存在的“学生中心”实现难、知识点“散”联系难及“理科思维”教学互动难三大难点问题,教学团队进行了“多元互动”课堂教学模式的建构与实施,在教学内容、教学方法、课程考核方面进行了全面改革。教学内容上增加了... 详细信息

针对无机化学教学中存在的“学生中心”实现难、知识点“散”联系难及“理科思维”教学互动难三大难点问题,教学团队进行了“多元互动”课堂教学模式的建构与实施,在教学内容、教学方法、课程考核方面进行了全面改革。教学内容上增加了有助于发展学生探究意识与创新能力的部分并有机融入课程思政。教学方法建立多元互动课堂,通过生活化教学、任务与问题驱动、学生评讲作业、微课与思维导图教学等方式引导学生自主参与、合作学习,帮助学生进行知识难点的突破,提高学生学习积极性和学习效率。课程考核重视学生参与,增加过程环节的评价。通过创新实践,突破了教学难点,学生的知识迁移灵活运用能力得以提升,语言表达、团队合作能力得以加强,个人自信与专业自信得以增强。

关键词：无机化学多元互动教学创新课程思政

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花生籽仁蔗糖含量遗传模型分析

作物学报 2024年第1期50卷 32-41页

作者：郅晨阳薛晓梦吴洁李雄才王瑾晏立英王欣陈玉宁康彦平王志慧淮东欣洪彦彬姜慧芳雷永廖伯寿中国农业科学院油料作物研究所/农业农村部遗传育种重点实验室湖北武汉430062 襄阳市农业技术推广中心湖北襄阳441021 河北省农林科学院粮油作物研究所河北石家庄050035 广东省农业科学院作物研究所广东广州510640

花生是我国重要的经济作物之一,约40%的花生用于食用加工。蔗糖含量作为影响花生品质的重要指标,与其风味及口感呈显著正相关。因此,提高花生籽仁中蔗糖含量对花生品质改良具有重要意义。本研究利用NYBP×SYT5-1和19-1934×JHT1两个F2:... 详细信息

花生是我国重要的经济作物之一,约40%的花生用于食用加工。蔗糖含量作为影响花生品质的重要指标,与其风味及口感呈显著正相关。因此,提高花生籽仁中蔗糖含量对花生品质改良具有重要意义。本研究利用NYBP×SYT5-1和19-1934×JHT1两个F2:3群体为试验材料,分析花生籽仁蔗糖含量遗传模型,同时分析了蔗糖含量与含油量、蛋白含量及籽仁相关性状间的相关性。结果表明,花生籽仁蔗糖含量呈连续分布,超亲分离现象明显且具有丰富变异。两群体中蔗糖含量与含油量均呈现显著负相关,与蛋白质含量均显著正相关,蔗糖含量与籽仁长、籽仁宽和百仁重的相关性在两群体间表现不一致。遗传分析结果表明,在两群体中花生籽仁蔗糖含量都表现为主要受两对主基因的加性、显性效应调控,存在明显互作,且主基因间具有累加效应。本研究通过对籽仁蔗糖含量遗传模型分析,初步了解了蔗糖含量的遗传规律,对食用花生品种选育具有指导意义。

关键词：花生蔗糖含量含油量相关性分析遗传模型

A deoxidation thermodynamic model for 304 stainless steel considering multiple-components coupled reactions

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Journal of Iron and Steel Research International 2024年第1期31卷 74-91页

作者： yan yan Guang-hao Shang li-ping Zhang Shao-ying li Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Henan Jinhui Stainless Steel Industry Group Co. Ltd.Xuchang461500HenanChina Changge Jinhui Recycling Metal R&D Co. Ltd.Xuchang461500HenanChina

A thermodynamic model for predicting the equilibrium oxygens of 304 stainless steel was developed based on the theory of slag-steel equilibrium,the law of mass conservation,and the ion and molecule coexistence *** the developed model,the Fe-Cr-Mn-Si-Al-S-O-melts reaction system and CaO-MgO-CaF_(2)-FeO-MnO-Al_(2)O_(3)-SiO_(2)-Cr2O_(3)slags were *** oxygen contents calculated by the model are in good agreement with experimental results and reference *** equilibrium oxygen contents in 304 stainless steel mainly decrease with increasing binary basicity(w(CaO)/w(SiO_(2)),where w(i)is the mass percentage of component i)and decreasing *** binary basicity at 2.0 while maintaining temperatures lower than 1823 K will keep the oxygen contents in the 304 stainless steel lower than 15×10^(-6).The equilibrium oxygen contents may also be decreased with increasing content of MgO in slags,which is more significant at lower binary ***,a small amount of FeO,MnO,and Al_(2)O_(3)(about 0-2.5 wt.%)in slags has little effect on equilibrium oxygen ***,it is found that the[C]-[O]reaction may occur during refining process but will not significantly affect the equilibrium oxygen contents.

关键词： Complex deoxidation Thermodynamic model Ion and molecule coexistence theory 304 stainless steel Slag-steel reaction

Identification of risk genes in Chinese nonobstructive azoospermia patients based on whole-exome sequencing

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Asian Journal of Andrology 2023年第1期25卷 66-72页

作者： Yu-Jun liu Xin-Jie Zhuang Jian-Ting An Hui Jiang Rong li Jie Qiao li-ying yan Xu Zhi Center for Reproductive Medicine Department of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China National Clinical Research Center for Obstetrics and Gynecology Beijing 100191China Key Laboratory of Assisted Reproduction Peking UniversityMinistry of EducationBeijing 100191China Peking-Tsinghua Center for life Sciences Peking UniversityBeijing 100191China Department of Urology Peking University Third HospitalBeijing 100191China Department of Andrology Peking University Third HospitalBeijing 100191China

Nonobstructive azoospermia(NOA)is a severe condition in infertile men,and increasing numbers of causative genes have been identified during the last few *** certain causative genes can explain the presence of NOA in some patients,a proportion of NOA patients remain to be *** study aimed to investigate potential high-risk genes associated with spermatogenesis in idiopathic NOA patients by whole-exome ***-exome sequencing was performed in 46 male patients diagnosed with ***,screening was performed for 119 genes known to be related to male ***,further screening was performed to determine potential high-risk causative genes for NOA by comparisons with 68 healthy male ***,risk genes with high/specific expression in the testes were selected and their expression fluctuations during spermatogenesis were *** frequency of cystic fibrosis transmembrane conductance regulator(CFTR)gene pathogenic variant carriers was higher in the NOA patients compared with the healthy *** risk genes that may be causes of NOA were identified,including seven genes that were highly/specifically expressed in the *** risk genes previously reported to be involved in spermatogenesis(MutS homolog 5[MSH5],cilia-and flagella-associated protein 54[CFAP54],MAP7 domain containing 3[MAP7D3],and coiled-coil domain containing 33[CCDC33])and three novel risk genes(coiled-coil domain containing 168[CCDC168],chromosome 16 open reading frame 96[C16orf96],and serine protease 48[PRSS48])were identified to be highly or specifically expressed in the testes and significantly different in the 46 NOA patients compared with 68 healthy *** study on clinical NOA patients provides further evidence for the four previously reported risk *** present findings pave the way for further functional investigations and provide candidate risk genes for genetic diagnosis of NOA.

关键词： cystic fibrosis transmembrane conductance regulator nonobstructive azoospermia potential risk genes spermatogenesis whole-exome sequencing

Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research International 2024年第4期31卷 894-908页

作者： yan-li Xin Zhi-ying Gao Bo Tian Qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter