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经纬仪水平角观测精度的研究

工程勘察 2005年第3期33卷 46-49,65页

作者：陆学智上海岩土工程勘察设计院有限公司上海200002

如何评定经纬仪水平角观测的精度 ,探求按菲律罗公式计算的测角中误差与各测站平差后单位权方向中误差的平均值和不同测回数之间合适的数学表达式 ,是三角测量中具有实际意义的重要研究课题。本文根据 2 3个高精度短边三角网和 3个城市... 详细信息

如何评定经纬仪水平角观测的精度 ,探求按菲律罗公式计算的测角中误差与各测站平差后单位权方向中误差的平均值和不同测回数之间合适的数学表达式 ,是三角测量中具有实际意义的重要研究课题。本文根据 2 3个高精度短边三角网和 3个城市二等网的实测资料统计结果 ,对有关经验估算公式 ,系统与偶然误差的分析、检验、影响比例和最适宜测回数等进行了研究。

关键词：经纬仪水平角观测精度数学表达式系统误差影响系数最适宜测回数

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机翼边界层的横流稳定性分析和转捩预测

空气动力学学报 2014年第1期32卷 14-20页

作者：黄章峰逯学志于高通天津大学力学系天津300072 空气动力学国家重点实验室四川绵阳621000

通过求解经典O-S方程(LST)、扩展的O-S方程(EOS)和线性抛物化稳定性方程(LPSE),对展向无限长、后掠角25°、迎角0°、来流Mach数0.8、单位Reynolds数6.79×106/m的机翼边界层进行了稳定性分析,结合eN方法进行了转捩预测。研究发现无限... 详细信息

通过求解经典O-S方程(LST)、扩展的O-S方程(EOS)和线性抛物化稳定性方程(LPSE),对展向无限长、后掠角25°、迎角0°、来流Mach数0.8、单位Reynolds数6.79×106/m的机翼边界层进行了稳定性分析,结合eN方法进行了转捩预测。研究发现无限长后掠机翼在(x,ω)平面上的中性曲线没有下支,在(x,β)平面上的中性曲线呈反拇指的形状,横流不稳定性在机翼前缘占主导作用。当外界扰动进入边界层后,幅值将被直接放大,对于频率相同的扰动,首先是展向波数β大的增长起来,演化到一定位置开始衰减,然后是展向波数β小的逐渐增长起来,并且增长的指数N逐步超过波数大的扰动。转捩在机翼前缘完成,引起转捩的扰动波的展向波长约为2mm。

关键词：流动稳定性分析转捩预测横流不稳定性后掠机翼抛物化稳定性方程

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多功能钻井液固井技术研究

天然气工业 1998年第3期18卷 52-54页

作者：金学智路宁长庆石油勘探局钻采工艺研究院

以高炉矿渣为水化材料，使钻井液转化为水泥浆固井技术，与多功能钻井液固井工艺技术相结合，井壁形成可固化的坚硬的泥饼，有助于地层封隔，减少或阻止循环漏失和固井注水泥中水泥浆通过漏失层位的液柱回落。多功能钻井液可以提高井眼... 详细信息

以高炉矿渣为水化材料，使钻井液转化为水泥浆固井技术，与多功能钻井液固井工艺技术相结合，井壁形成可固化的坚硬的泥饼，有助于地层封隔，减少或阻止循环漏失和固井注水泥中水泥浆通过漏失层位的液柱回落。多功能钻井液可以提高井眼的完整性和固井注水泥质量。文中介绍对调整井设计密度为１．１６ｇ／ｃｍ３，用高炉矿渣代替重晶石加重的多功能钻井液。试验研究了矿渣钻井液固化液在多功能钻井液中的扩散过程和矿渣钻井液固化液的抗压强度、流变性、稳定性等性能。研究结果表明：矿渣钻井液固化液中的激活剂能扩散到泥饼和残留于环空中的钻井液中，使钻井液滤饼和残留于环空中的钻井液全部固化，实现第一界面、第二界面的良好胶结，防止油气水窜，提高固井质量。矿渣钻井液固化液抗压强度高，流变性和稳定性好，有利于提高固井质量。多功能钻井液固井技术对提高水平井固井质量有较大的技术优势，建议研究应用。

关键词：固井注水泥钻井液油田

《食品理化检测技术》课程思政要素挖掘的思考与实践

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现代食品 2023年第24期29卷 22-24页

作者：严玉玲豆一玲卢学智吕晨晨郭焰新疆轻工职业技术学院新疆乌鲁木齐830021

食品理化检测技术是现代食品科学的重要组成部分,其通过对食品中各种成分的定性和定量分析,可以为食品质量评价、安全检验和生产加工提供科学依据。《食品理化检测技术》课程不仅需要关注学生的专业知识与技能培养,还需注重思政教育的... 详细信息

食品理化检测技术是现代食品科学的重要组成部分,其通过对食品中各种成分的定性和定量分析,可以为食品质量评价、安全检验和生产加工提供科学依据。《食品理化检测技术》课程不仅需要关注学生的专业知识与技能培养,还需注重思政教育的渗透与实践。基于此,本文探讨了如何在《食品理化检测技术》课程中挖掘思政要素,旨在通过实践活动的方式,提升思政教育成效。

关键词：食品理化检测技术思政要素挖掘思考与实践

《食品理化检测技术》课程思政要素挖掘的思考与实践

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现代食品 2023年第22期29卷 89-91页

作者：严玉玲豆一玲卢学智吕晨晨郭焰新疆轻工职业技术学院新疆乌鲁木齐830021

食品质量与人民群众的身体健康息息相关,因此,食品行业的从业人员必须具备扎实的专业技能以及正确的伦理道德观念和社会责任感。基于此,本文分析了如何在《食品理化检测技术》课程中挖掘思政要素,以供参考。

关键词：食品理化检测技术思政要素挖掘思考与实践

Coupling non-isothermal trickle-bed reactor with catalyst pellet models to understand the reaction and diffusion in gas oil hydrodesulfurization

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1095-1106页

作者： Xingqiang Zhao Changfeng Yang Mengke lu Yao Shi Gang Qian Xinggui Zhou xuezhi Duan State Key Laboratory of Chemical Engineering East China University of Science and Technology130 Meilong RoadShanghai 200237China

In this work,a trickle-bed reactor coupled with catalyst pellet model is employed to understand the effects of the temperature and catalyst pellet structures on the reaction-diffusion behaviors in gas oil hydrodesulfurization(HDS).The non-isothermal reactor model is determined to be reasonable due to non-negligible temperature variation caused by the reaction *** reaction rate along the reactor is mainly dominated by the temperature,and the sulfur concentration gradient in the catalyst pellet decreases gradually along the reactor,leading to the increased internal effectiveness *** the fixed catalyst bed volume,there exists a compromise between the catalyst reaction rate and effectiveness *** commonly studied catalyst pellet size of 0.8-3 mm and porosity of 0.4-0.8,an optimization of the temperature and catalyst pellet structures is carried out,and the optimized outlet sulfur content decreases to 7.6 wppm better than the commercial level at 0.96 mm of the catalyst pellet size and 0.40 of the catalyst porosity.

关键词： Hydrodesulfurization Catalyst pellet Trickle-bed reactor Coupling model Reaction-diffusion behavior

Sentinel-1 EW mode dataset for Antarctica from 2014–2020 produced by the CASEarth Cloud Service Platform

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Big Earth Data 2022年第4期6卷 385-400页

作者： Dong Liang Huadong Guo lu Zhang Haipeng Lia xuezhi Wang Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina International Research Center of Big Data for Sustainable Development Goals BeijingChina Computer Network Information Center Chinese Academy of SciencesBeijingChina

Antarctica plays an important role in research on global change,and its unique geography,ocean,climate,and environment pro-vide an ideal place for humankind to understand Earth’s *** sensing provides an effective means to monitor and observe large-scale processes on the *** aperture radar(SAR)in particular provides the capability for all-weather Earth *** Sentinel-1A and Sentinel-1B SAR satellites have ideal ground coverage and imaging frequency for observing *** study developed a dataset of 69,586 Sentinel-1 EW mode satellite images of the Antarctic ice sheet from October 2014 to December *** dataset was processed with the European Space Agency Sentinel Application Platform(SNAP)and a Python batch scheduling tool on the Big Earth Data Cloud Service Platform of the Chinese Academy of Sciences Big Earth Data Science Engineering Program(CASEarth).Several data processing operations were implemented to process the raw dataset,including radiometric calibration,invalid edge removal,geocoding,data reprojection to an Antarctic projection,data compression to TIFF format,and construction of image *** dataset is avail-able at http://***/10.11922/sciencedb.j00076.00085.

关键词： Big Earth data CASEarth cloud computing Sentinel-1 Antarctica

Explosion limits estimation and process optimization of direct propylene epoxidation with H2 and O2

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Chinese Journal of Chemical Engineering 2019年第12期27卷 2968-2978页

作者： Mengke lu Yanqiang Tang Wenyao Chen Guanghua Ye Gang Qian xuezhi Duan Weikang Yuan Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

Direct propylene epoxidation with H2 and O2,an attractive process to produce propylene oxide(PO),has a potential explosion danger due to the coexistence of flammable gases(i.e.,C3 H6 and H2)and oxidizer(i.e.,O2).The unknown explosion limits of the multi-component feed gas mixture make it difficult to optimize the reaction process under safe operation *** this work,a distribution method is proposed and verified to be effective by comparing estimated and experimental explosion limits of more than 200 kinds of flammable gas ***,it is employed to estimate the explosion limits of the feed gas mixture,some results of which are also validated by the classic Le Chatelier’s Rule and flammable resistance *** on the estimated explosion limits,process optimization is carried out using commercially high and inherently safe reactant concentrations to enhance reaction *** promising results are directly obtained through the interface called gOPT in gPROMS only by using a simple,easy-constructed and mature packed-bed reactor,such as the PO yield of 13.3%,PO selectivity of 85.1%and outlet PO fraction of 1.8%.These results can be rationalized by indepth analyses and discussion about the effects of the decision variables on the operation safety and reaction *** insights revealed here could shed new light on the process development of the PO production based on the estimation of the explosion limits of the multi-component feed gas mixture containing flammable gase s,inert gas and O2,followed by process optimization.

关键词： Direct propylene epoxidation with H2/O2 Propylene oxide Safe operation Explosion limits estimation Process optimization

Curative efficacy of extract from Ganjiangdazao recipe on functional dyspepsia in rats

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Journal of Traditional Chinese Medicine 2020年第4期40卷 654-663页

作者： Gao lujiao Niu Xin Niu Tingli Wang Xuan lu Xiaoyan Feng Qianjin Yang xuezhi School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China Medical Department Dongfang HospitalBeijing University of Chinese MedicineBeijing 100078China Graduate School Shanxi University of Chinese MedicineTaiyuan 030619China Beijing University of Chinese Medicine Libraries Beijing 100029China Shanxi Modern Chinese Medicine Engineering Laboratory Shanxi University of Chinese MedicineTaiyuan 030619China

OBJECTIVE:To evaluate the efficacy of the extract from Ganjiangdazao recipe(EGR)on functional dyspepsia in rats with spleen-stomach deficiency cold pattern(SSDCP)in terms of Traditional Chinese Medicine,and to investigate its ***:Sixty Sprague-Dawley rats were randomly divided into the control group,SSDCP group,low-EGR SSDCP group,high-EGR SSDCP group,probiotics group,EGR *** model was induced by gavage with the 0℃edible *** symptoms and manifestations were scored by method from the relative literature,the ecological changes in cecal microflora was analyzed by 16SrRNA high-throughput sequencing technology,gastric tissues were treated by immunohistochemistry,the levels of related biochemical components related to the gastrointestinal functions were detected by enzyme-linked immunosorbent assay and colorimetry,gastric juice was measured by pH meter,blood pressure measurement by trapping tail method,surface temperature measured by infrared thermal imaging,and the content of 6-gingerol in the serum was determined by liquid-mass chromatography before and after EGR was ***:It was found that EGR could effectively relieve the symptoms and manifestations of the SSDCP rats(Plue of the relative abundance of Lactobacillus,Streptococcus,Enterococcus and Coprobacillus increased,while the value of the relative abundance of Clostridium decreased(P<0.05)in the cecal microflora in the SSDCP rats after high-EGR administration;It was also found that EGR had no substantial effect on the related biochemical components related to the gastrointestinal functions of in the SSDCP rats;and a certain amount of 6-gingerol was detected in the serum of EGR ***:The pharmacodynamic site of EGR is the intestinal tract,and the mechanism behind the effect of EGR on SSDCP rats,involves increasing the beneficial bacteria and decreasing the proinflammatory bacteria in the intestinal *** blood pharmacodynamics of EGR remains to

关键词： Dyspepsia Deficiency cold of spleen and stomach High-throughput nucleotide sequencing Probiotics Cecal microflora Ganjiangdazao recipe