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Particuology 2024年第4期87卷 37-45页

作者： Zhuoyue Xu Xiao Wang biao jin Dawang Zhang Hui Li College of Materials Science and Engineering Xi'an University of Architecture and TechnologyXi'an710055China Schoolof Materials and Chemical Engineering Henan University of Urban ConstructionPingdingshan46736China

This paper investigates the impact of flue gas desulfurization(FGD)gypsum's crystal modifier on the characteristics and microcosmic mechanism ofα-high strength gypsum.The results demonstrate that all three crystal modifiers can convert FGD gypsum toα-high-strength gypsum.Citric acid(CA)has the most significant influence onα-high-strength gypsum,and the preparedα-high-strength gypsum is short columnar,with an aspect ratio in the range of 1-3,and has a faster setting time,a larger specific surface area,and a smaller standard consistency,higher compressive strength,greater surface hardness,and smaller crystal particle size.The initial setting time of theα-high-strength gypsum manufactured with CA crystal modifier was decreased by 36%compared to the blank sample,the final setting time was lowered by 37.5%,and the water consumption of the standard consistency was reduced by 8%.The maximum strength is 32 MPa after 2 h,the absolute dry compressive strength is up to 38 MPa,and the surface hardness is improved by 24.43%.

关键词： Flue gas desulfurization gypsum Crystal modifier Microscopic mechanism α-high-strength gypsum

High-resolution neutronics model for ^(238)Pu production in high-flux reactors

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Nuclear Science and Techniques 2024年第5期35卷 226-236页

作者： Qing-Quan Pan Qing-Fei Zhao Lian-Jie Wang Bang-Yang Xia Yun Cai jin-biao Xiong Xiao-jing Liu School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux reactors.The filter burnup and single energy burnup methods have no theoretical approximation and can achieve a spectrum resolution of up to~1 eV,thereby constructing the importance curve and yield curve of the full energy range.The burnup extreme analysis method combines the importance and yield curves to consider the influence of irradiation time on production efficiency,thereby constructing extreme curves.The three curves,which quantify the transmutation rate of the nuclei in each energy region,are of physical significance because they have similar distributions.A high-resolution neutronics model for ^(238)Pu production was established based on these three curves,and its universality and feasibility were proven.The neutronics model can guide the neutron spectrum optimization and improve the yield of ^(238)Pu by up to 18.81%.The neutronics model revealed the law of nuclei transmutation in all energy regions with high spectrum resolution,thus providing theoretical support for high-flux reactor design and irradiation production of ^(238)Pu.

关键词： ^(238)Pu Neutronics model High-flux reactor Spectrum resolution Spectrum optimization

Structural characteristic and formation mechanism of hemihydrate calcium sulfate whiskers prepared using FGD gypsum

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Particuology 2022年第3期20卷 98-103页

作者： Xiaoting Zhang Lingwei Ran Xiao Wang biao jin Jianwu Zhang Shanying Li Liushuan Yang Department of Civil&Material Engineering Henan University of Urban ConstructionPingdingshan 467036HenanChina不详

Hemihydrate calcium sulfate whiskers(HH-CSWs)were hydrothermally synthesized in a sulfuric acid solution at 120℃ for different holding times(20,40,and 60 min).The phase structures and morphologies were characterized by XRD and SEM,respectively.The XRD pattern of the sample under 60 min was refined via the Rietveld fitting method.The structure models of the HH-CSW sample under a 60-min holding time was established based on Rietveld fitting results.No difference in the positions of diffraction peaks was determined.The as-prepared holding time increased the intensity and aspect ratio of the diffraction peaks of both samples.In the prepared HH-CSW structure,Ca-O polyhedron is a 12-sided polyhedron similar to that in the gypsum structure;the Ca atom is located in two positions in the one-unit cell;the H_(2)O channel along the c-axis similar is O-shaped and bigger than that in hexagonal and monoclinic CaSO_(4)·0.5H_(2)O structures.Therefore,although the prepared HH-CSW crystals’structure are similar to that of the reported hexagonal and monoclinic CaSO_(4)·0.5H_(2)O structures,they are not the same.The formation mechanism of HH-CSW from flue gas desulfurization(FGD)gypsum is discussed based on the analysis of gypsum structure.

关键词： FGD gypsum HH-CSW Rietveld method Crystal structure

Application Analysis of Various Geophysical Methods in Volume Calculation of Different Landfills

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Open Journal of Geology 2022年第9期12卷 706-716页

作者： jinsuo Liu biao jin Anhui Construction Engineering Testing and Research Institute Hefei China Anhui Urban Construction Design Institute Co. Ltd. Hefei China

Garbage disposal has gradually become a key issue faced by environmental governance. What must be controlled in garbage disposal is the calculation of garbage volume. In this paper, according to the different landfill conditions of a landfill in Anhui, including: covering soil, overlying HDPE membrane, overlying concrete, etc., combined with the physical differences between the rock mass and the garbage at the bottom of the landfill. The landfill covered with HDPE membrane adopts the transient electromagnetic method, the landfill covered with soil layer adopts the high-density electrical method, and the landfill covered with concrete adopts the combination of transient electromagnetic method and ground penetrating radar. At the same time, Combines the borehole data to determine that the resistivity value of the interface between the garbage and the soil was 29 Ω⋅m. Finally, the sections of multiple survey lines can accomplish three-dimensional stereoscopic that calculate the distribution and actual volume of the garbage. This method is used to determine the final investment cost.

关键词： Garbage Volume Geophysical Exploration Transient Electromagnetic Method High-Density Electrical Method Ground Penetrating Radar

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机器学习在化合物属性预测中的应用

环境化学 2024年第1期43卷 69-81页

作者：王紫维韩民金彪中国科学院广州地球化学研究所有机地球化学国家重点实验室广州510640 中国科学院深地科学卓越创新中心广州510640 中国科学院大学北京100049

化合物的属性预测是药物研发、毒理学研究、环境行为预测等工作的核心任务.目前,人工合成的化学物质层出不穷,相关的实验研究数据在持续扩充,但实验研究数据远无法赶超新型化学物质的研发速度.近年来,机器学习算法及模型在化合物属性预... 详细信息

化合物的属性预测是药物研发、毒理学研究、环境行为预测等工作的核心任务.目前,人工合成的化学物质层出不穷,相关的实验研究数据在持续扩充,但实验研究数据远无法赶超新型化学物质的研发速度.近年来,机器学习算法及模型在化合物属性预测方面展现了独特的优势和巨大的潜力,尤其在实验数据匮乏的情况下,提供了可靠的模型预测数据.本文介绍了机器学习应用于化合物属性预测的主要流程步骤和相应的模块的内容,涵盖数据集、分子描述方法、模型性能评估指标和评估方法等.同时,本文系统总结了机器学习方法在化合物物理化学性质预测、生物活性预测和毒性预测方面的应用实例,并从数据集、分子特征化、模型解释等方面分析并讨论了相关研究工作现存问题与未来挑战.

关键词：机器学习化合物属性分子结构模型预测

Performance analysis of SBAS ephemeris corrections and integrity algorithms in China region

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Satellite Navigation 2021年第1期2卷 213-226页

作者： biao jin Shanshan Chen Dongjun Li Yuechen Wang Elhadi Takka Space Star Technology Co. Ltd.Beijing 100194China Yunnan Observatory Chinese Academy of SciencesKunming 650011China UniStrong Science Technology Co. Ltd.Beijing 100176China Ecole Militaire Polytechnique 16024 AlgerAlgeria.

Satellite Based Augmentation Systems(SBASs)improve the positioning accuracy and integrity by broadcasting to the civil aviation community the corrections and integrity parameters.A snapshot algorithm based on the minimum variance estimation is investigated in this study to calculate the satellite clock and orbit corrections.A chi-square test is performed on the remaining errors in the corrected ephemeris to guarantee the integrity.User Differential Range Error(UDRE)and scaling matrix contained in Message Type 28 are derived using the covariance information based on the assumption that one of the reference stations failed.A software package is developed and applied in the real data collected at 26 stations.International GNSS(Global Navigation Satellite System)Service(IGS)precise clock and orbit products are taken as the references to assess the accuracy of corrections.For both Global Positioning System(GPS)and BeiDou Navigation Satellite System(BDS),the range accuracy of 0.10 m can be achieved with the employment of the derived corrections.No obvious performance difference between GPS and BDS is found.UDREs for all visible satellites are generated with the maximum index of 12 and minimum index of 3.The geometric range differences calculated with IGS precise products and broadcast ephemeris are employed to assess the integrity of UDRE.It is found that the UDRE is able to bound the residuals with 99.9%confidence which meet the requirement of aviation users.With ionospheric delay corrected by Global Ionosphere Map(GIM),the positioning accuracy of 0.98 m with GPS corrections and 0.80 m with multi-constellation augmentation can be achieved which indicates a significant improvement of GPS standalone results.

关键词： SBAS Minimum variance estimation Ephemeris correction UDRE

The Jasmine(Jasminum sambac)Genome Provides Insight into the Biosynthesis of Flower Fragrances and Jasmonates

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Genomics, Proteomics & Bioinformatics 2023年第1期21卷 127-149页

作者： Gang Chen Salma Mostafa Zhaogeng Lu Ran Du Jiawen Cui Yun Wang Qinggang Liao jinkai Lu Xinyu Mao Bang Chang Quan Gan Li Wang Zhichao Jia Xiulian Yang Yingfang Zhu Jianbin Yan biao jin College of Horticulture and Plant Protection Yangzhou UniversityYangzhou 225009China College of Bioscience and Biotechnology Yangzhou UniversityYangzhou 225009China Department of Floriculture Faculty of AgricultureAlexandria UniversityAlexandria 21526Egypt Key Laboratory of Plant Functional Genomics of the Ministry of Education Yangzhou UniversityYangzhou 225009China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureKey Laboratory of Synthetic BiologyMinistry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China College of Landscape Architecture Nanjing Forestry UniversityNanjing 210037China Institute of Plant Stress Biology State Key Laboratory of Cotton BiologyDepartment of BiologyHenan UniversityKaifeng 475001China

Jasminum sambac(jasmine flower),a world-renowned plant appreciated for its exceptional flower fragrance,is of cultural and economic importance.However,the genetic basis of its fragrance is largely unknown.Here,we present the first de novo genome assembly of J.sambac with 550.12 Mb(scaffold N50=40.10 Mb)assembled into 13 pseudochromosomes.Terpene synthase(TPS)genes associated with flower fragrance are considerably amplified in the form of gene clusters through tandem duplications in the genome.Gene clusters within the salicylic acid/benzoic acid/theobromine(SABATH)and benzylalcohol O-acetyltransferase/anthocyanin O-hydroxycinnamoyltransferases/anthranilate N-hydroxycinnamoyl/benzoyltransferase/deacetylvindoline 4-O-acetyltransferase(BAHD)superfamilies were identified to be related to the biosynthesis of phenylpropanoid/benzenoid compounds.Several key genes involved in jasmonate biosynthesis were duplicated,causing an increase in copy numbers.In addition,multi-omics analyses identified various aromatic compounds and many genes involved in fragrance biosynthesis pathways.Furthermore,the roles of JsTPS3 in b-ocimene biosynthesis,as well as JsAOC1 and JsAOS in jasmonic acid biosynthesis,were functionally validated.The genome assembled in this study for J.sambac offers a basic genetic resource for studying floral scent and jasmonate biosynthesis,and provides a foundation for functional genomic research and variety improvements in Jasminum.

关键词： Jasmine flower Jasminum sambac Genome Jasmonate Flower fragrance

β-内酰胺类抗生素过敏对开腹胃癌根治术患者手术部位感染的影响

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医药论坛杂志 2024年第7期45卷 757-760,765页

作者：靳金彪濮阳油田总医院胃肠外科河南濮阳457000

目的探讨和β-内酰胺类(beta-lactam,BL)抗生素非过敏患者相比较,BL过敏是否会增加开腹胃癌根治手术患者手术部位感染(surgical site infection,SSI)的发病率。方法选取2018年3月—2023年2月在濮阳油田总医院进行治疗的胃癌行开腹手术患... 详细信息

目的探讨和β-内酰胺类(beta-lactam,BL)抗生素非过敏患者相比较,BL过敏是否会增加开腹胃癌根治手术患者手术部位感染(surgical site infection,SSI)的发病率。方法选取2018年3月—2023年2月在濮阳油田总医院进行治疗的胃癌行开腹手术患者303例。根据患者BL过敏状况对其进行分组,病历中术前报告BL过敏患者作为过敏组,病历中术前未报告BL过敏患者作为非过敏组。对比两组患者的SSI发病率。应用logisitic回归模型探讨影响患者术后SSI发病的相关因素。结果303例胃癌开腹手术患者中,术后SSI发病率4.29%。其中:BL过敏组患者SSI发病率15.38%;非BL过敏组SSI发病率3.79%。差异有统计学意义(P<0.05);在排除预防性应用BL类、非BL类抗生素因素作为自变量的条件下,年龄大、糖尿病、手术风险分级高、术中输血、BL过敏是患者发生SSI的危险因素(P<0.05);在纳入预防性应用BL类、非BL类抗生素因素作为自变量的条件下,腹部手术史、糖尿病、手术风险分级高、应用非BL类抗生素是患者SSI发病的危险因素(P<0.05)。结论BL过敏患者SSI增加的原因可能与其非BL类抗生素用药方案有关。

关键词：抗生素过敏切口感染

基于OPPERMANN序列扩频的雷达通信一体化波形设计

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火力与指挥控制 2024年第1期49卷 25-34页

作者：宋志超靳标武浩正国光电器股份有限公司广州510800 江苏科技大学海洋学院江苏镇江212003

共享波形设计是雷达通信一体化系统最大化资源利用效率的关键。针对现有的一体化波形多址通信功能欠缺问题,设计了一种基于OPPERMANN序列扩频的雷达通信一体化波形。利用OPPERMANN序列对雷达脉冲信号进行加权,在子脉冲内调制多个下行链... 详细信息

共享波形设计是雷达通信一体化系统最大化资源利用效率的关键。针对现有的一体化波形多址通信功能欠缺问题,设计了一种基于OPPERMANN序列扩频的雷达通信一体化波形。利用OPPERMANN序列对雷达脉冲信号进行加权,在子脉冲内调制多个下行链路用户的通信信号,并采用正交的OPPERMANN序列对不同用户的通信信号和雷达信号进行扩频,从而实现雷达与通信双重功能。理论分析和仿真实验表明,所设计的一体化波形使雷达和通信信号共享同一频带,不仅可以同时与多个下行链路的用户进行通信,还具有不同类型的模糊函数,可以满足雷达系统在目标探测和目标跟踪场景下的波形设计需求。

关键词：雷达通信一体化共享波形设计 OPPERMANN序列模糊函数误码率

跨界搜寻联合与匹配平衡对企业技术创新绩效的影响——知识耦合的中介作用与柔性惯例的调节作用

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软科学 2024年第2期38卷 95-102,144页

作者：朱云鹃陈金标安徽大学商学院合肥230601

以组织边界管理理论为基础探讨跨界搜寻联合与匹配平衡对企业技术创新绩效的影响,以及替代性与互补性知识耦合起到的中介作用,柔性惯例对知识耦合与企业技术创新绩效之间关系的调节作用。基于我国139家高科技企业调研问卷的数据分析,结... 详细信息

以组织边界管理理论为基础探讨跨界搜寻联合与匹配平衡对企业技术创新绩效的影响,以及替代性与互补性知识耦合起到的中介作用,柔性惯例对知识耦合与企业技术创新绩效之间关系的调节作用。基于我国139家高科技企业调研问卷的数据分析,结果发现:跨界搜寻联合与匹配平衡均正向影响企业技术创新绩效;知识耦合在跨界搜寻平衡与企业创新关系中起到中介作用;且柔性惯例正向调节知识耦合对企业技术创新绩效的影响。

关键词：跨界搜寻平衡知识耦合柔性惯例企业技术创新绩效