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天然来源的表面活性剂在超低渗油藏开发中的应用

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当代化工 2024年第6期53卷 1277-1281页

作者：王金山秦瑞廖鑫羽李佳豪王超陶震广东南油服务有限公司海口分公司海南海口570100

因为国内大部分油田目前已经进入开发后期,在孔渗较好的圈闭已经钻探殆尽的大背景下,超低渗油藏开发便成了主要研究方向。在开发实践中,采用皂苷为原料制备了一种新型表面活性剂,这种活性剂为天然来源,并通过界面张力、接触角和石油采... 详细信息

因为国内大部分油田目前已经进入开发后期,在孔渗较好的圈闭已经钻探殆尽的大背景下,超低渗油藏开发便成了主要研究方向。在开发实践中,采用皂苷为原料制备了一种新型表面活性剂,这种活性剂为天然来源,并通过界面张力、接触角和石油采收率评估等实验说明其在以碳酸盐岩为代表的超低渗储层中具有良好的应用价值。评估了表面活性剂产生泡沫并在微观和宏观尺度上建立稳定乳液的能力。研究结果表明,当表面活性剂质量浓度达到1800 mg·L^(-1)时,界面张力将大幅度降低,最低达到0.39 mN·m^(-1)。此外,通过优化盐度,界面张力将降低到最低0.36 mN·m^(-1),这表明了盐度控制对于降低界面张力的作用。实验结果表明,该天然来源的新型表面活性剂在其临界胶束浓度下表现出优异的乳液稳定性,持续了6个月性质未发生显著变化;这种新型的表面活性剂产生的泡沫同样表现出了显著的稳定性,半衰期长达30 min。因此,在最佳条件下进行的驱油实验中,该新型表面活性剂溶液处于其临界胶束浓度并且盐度和碱度水平得到优化,原油采收率显著提高了25%,相比于传统的表面活性剂具有更为良好的化学性质,为未来的超低渗透油藏开发带来显著增益。

关键词：石油开发表面活性剂皂苷超低渗透油藏界面张力

Cerium refinement of grains and primary carbides during solidification of Cr_(4)Mo_(4)V bearing steel

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Journal of Rare Earths 2024年第4期42卷 783-792页

作者： Weifeng liu Jianqiang Wang Mingyue Sun Bin Xu jiahao Yao Qunbo Fan Dianzhong li Chongqing Innovation Center Beijing Institute of TechnologyChongqing401135China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The effect of cerium(Ce)on the solidification microstructure of Cr_(4)Mo_(4)V bearing steel was investigated via a combined experimental and theoretical *** a trace amount(0.056 wt%)of Ce addition,the coarse columnar grains in as-cast microstructure transform into equiaxed ones,and the average diameter is reduced from 56 to 27μ*** network-like and bulky primary MC and M2C carbides at the interdendritic regions become disconnected and refined,and their volume percentage decreases from4.15 vol%to 2.1 vol%.Ce-inclusions acting as heterogeneous nucleation agents of prior-austenite grains and Ce atoms segregating at grain boundaries,both contribute to the refinement of *** calculations reveal that primary carbides are precipitated afterγ-austenite forms near the end of the solidification *** modification of primary carbides in size and amount is mainly attributed to the isolated remaining melt separated by refinedγ-austenite grains in which the nucleation of carbides is promoted,while the growth is restrained owing to the less segregation of alloying elements.

关键词： Cr_(4)Mo_(4)V bearing steel Rare Earths Grains Primary carbides Refinement

Numerical and theoretical study of large-scale failure of strata overlying sublevel caving mines with steeply dipping discontinuities

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1799-1815页

作者： Kaizong Xia Zhiwei Si Congxin Chen Xiaoshuang li Junpeng Zou jiahao Yuan State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China School of Urban Construction Changzhou UniversityChangzhou 213164China Faculty of Engineering China University of Geosciences(Wuhan)Wuhan 430074China

The deformation and fracture evolution mechanisms of the strata overlying mines mined using sublevel caving were studied via numerical ***,an expression for the normal force acting on the side face of a steeply dipping superimposed cantilever beam in the surrounding rock was deduced based on limit equilibrium *** results show the following:(1)surface displacement above metal mines with steeply dipping discontinuities shows significant step characteristics,and(2)the behavior of the strata as they fail exhibits superimposition ***,failure first occurs in certain superimposed strata slightly far from the ***,with the constant downward excavation of the orebody,the superimposed strata become damaged both upwards away from and downwards toward the *** process continues until the deep part of the steeply dipping superimposed strata forms a large-scale deep fracture plane that connects with the *** deep fracture plane generally makes an angle of 12°-20°with the normal to the steeply dipping *** effect of the constant outward transfer of strata movement due to the constant outward failure of the superimposed strata in the metal mines with steeply dipping discontinuities causes the scope of the strata movement in these mines to be larger than *** strata in the metal mines with steeply dipping discontinuities mainly show flexural toppling ***,the steeply dipping structural strata near the goaf mainly exhibit shear slipping failure,in which case the mechanical model used to describe them can be simplified by treating them as steeply dipping superimposed cantilever *** taking the steeply dipping superimposed cantilever beam that first experiences failure as the key stratum,the failure scope of the strata(and criteria for the stability of metal mines with steeply dipping discontinuities mined using sublevel caving)can be obtained via iterative computations from the ke

关键词： sublevel caving mines universal distinct element code(UDEC)numerical approach large-scale ground movement steeply dipping superimposed cantilever beam toppling failure

Probabilistic life Calculation Method of NdFeB Based on Brittle Fatigue Damage Model

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 865-884页

作者： Lei li Guolai Yang jiahao li School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

This paper proposes a probabilistic life calculation method of NdFeB based on brittle fatigue damage ***,Zhu-Wang-Tang(ZWT)constitutive model considering strain rate is established,and based on this,a numerical co-simulation model for NdFeB life calculation is *** life distribution diagram of NdFeB under different stress levels is obtained after ***,a new model of brittle fatigue damage based on brittle damage mechanism is *** the parameters in the model are identified according to the life distribution diagram of NdFeB and the parameter distribution of the damage evolution model when applied to NdFeB is ***,the probability density evolution equation of NdFeB life calculation is established and solved using the probability density evolution *** density function(PDF)of NdFeB life under different stress levels is obtained and provides theoretical basis for the reliability of NdFeB in engineering applications.

关键词： NdFeB ZWT constitutive model fatigue life brittle damage probability density evolution

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雄性大鼠高原环境暴露生殖系统损伤研究

预防医学 2024年第8期36卷 727-730,736页

作者：卜子涵周浩李家豪张斌张春雷常德辉中国人民解放军联勤保障部队第九四〇医院泌尿外科甘肃兰州730050 中国人民解放军联勤保障部队第九四〇医院甘肃省干细胞与基因药物重点实验室甘肃兰州730050 甘肃中医药大学第一临床医学院甘肃兰州730000

目的探究高原环境暴露对雄性大鼠生殖系统的影响,为高原环境下生殖损伤机制研究提供依据。方法60只SPF级12周龄雄性Wistar大鼠随机分为平原组、高原1 d组、高原3 d组、高原7 d组、高原14 d组和高原28 d组。平原组大鼠在正常环境下常规饲... 详细信息

目的探究高原环境暴露对雄性大鼠生殖系统的影响,为高原环境下生殖损伤机制研究提供依据。方法60只SPF级12周龄雄性Wistar大鼠随机分为平原组、高原1 d组、高原3 d组、高原7 d组、高原14 d组和高原28 d组。平原组大鼠在正常环境下常规饲养28 d,各高原组大鼠置于模拟高原低压低氧动物实验舱暴露相应时间。各组大鼠完成饲养时间后麻醉处死,取睾丸组织和腹主动脉血。检测睾丸指数和精子质量;分析睾丸组织形态和细胞器形态;测定睾丸组织丙二醛(MDA)、超氧化物歧化酶(SOD)、活性氧(ROS),以及血清促卵泡激素(FSH)、黄体生成素(LH)和睾酮(T)。结果与平原组比较,高原14 d组大鼠睾丸指数、相对精子计数、精子活力和精子前向运动率降低;睾丸组织形态异常较明显,约翰逊评分较低;线粒体破裂,基质明显变浅,嵴大量断裂、缺失;睾丸组织MDA、ROS水平升高;血清FSH、LH水平降低,T水平升高(均P<0.05)。与高原14 d组比较,高原28 d组大鼠相对精子计数、精子活力和精子前向运动率升高;线粒体仍肿胀,但未见线粒体破裂;睾丸组织MDA、ROS水平降低,SOD水平升高;血清FSH、LH水平升高,T水平降低(均P<0.05)。结论高原环境可引起雄性大鼠睾丸指数、精子质量下降,线粒体功能受损,诱发氧化应激,从而影响雄性大鼠生殖系统;但随着暴露时间增加,大鼠生殖系统出现自我修复现象。

关键词：高原生殖系统睾丸氧化应激性激素

Fonsecaea monophora致皮肤着色芽生菌病1例

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中国感染与化疗杂志 2024年第3期24卷 338-340页

作者：陆丹倩郑永平李家豪张玲王巧媚邓聚辉彭明黄阶胜刘丽婷广东省中山市中医院检验科广东中山528400 中山大学孙逸仙纪念医院皮肤科广东省中山市中医院皮肤科广东中山528400

着色芽生菌病(chromoblastomycosis,CBM)是由暗色真菌引起皮肤及皮下组织的慢性肉芽肿性疾病,引起人类感染常见病原体主要为裴氏着色真菌(Fonsecaea pedrosoi)、***、***、***、卡氏枝孢瓶霉(Cladophialophora crrionii)、疣状瓶霉(Phialophora verrucosa)和播水喙枝孢霉(Rhinocladiella aquarspersa)等。裴氏着色真菌普遍存在于自然环境中,通常由微小外伤侵入皮肤引起致病,感染常发生于免疫功能正常人群。本文报道1例由***致皮肤着色芽生菌病。

关键词： Fonsecaeamonophora 着色芽生菌病伊曲康唑特比萘芬

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pH响应型智能食品包装材料的研究进展

塑料包装 2024年第4期34卷 1-8页

作者：李家豪黄杨宇瞿润怡侯茗萱王世波夏碧华江南大学化学与材料工程学院教育部合成与生物胶体重点实验室无锡214122

为避免粮食浪费,食品智能包装材料的研究迫在眉睫。相较于其他智能包装材料,pH响应型智能包装材料应用最为广泛。pH响应型智能包装材料主要是由pH指示剂(色素)和聚合物载体材料通过一定的方式组合而成。相比合成色素和合成聚合物基体,... 详细信息

为避免粮食浪费,食品智能包装材料的研究迫在眉睫。相较于其他智能包装材料,pH响应型智能包装材料应用最为广泛。pH响应型智能包装材料主要是由pH指示剂(色素)和聚合物载体材料通过一定的方式组合而成。相比合成色素和合成聚合物基体,天然色素具有丰富的颜色、易于获取、无毒、安全和高pH响应性等优势,天然生物聚合物具有良好的生物相容性、可用性、生物降解性、稳定性、无毒性和良好的成膜能力等优点。本文主要概述了pH响应型智能包装材料最新进展,且进一步探讨了该类型智能包装材料所面临的挑战和机遇。

关键词：智能食品包装天然色素生物聚合物研究进展

Variation characteristics of acid rain in Zhuzhou,Central China over the period 2011-2020

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Journal of Environmental Sciences 2024年第4期138卷 496-505页

作者： jiahao Ren liquan Zhu Xi Zhang Yuqian Luo Xuecai Zhong Bowen li Yuwen Wang Kai Zhang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Zhuzhou Environment Monitoring Center Zhuzhou 412000China Faculty of Environmental Engineering The University of Kitakyushu1–1 HibikinoWakamatsuKitakyushuFukuoka 808-0135Japan College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China

Zhuzhou was one of the most polluted cities in China with the serious acid *** to the implementation of air pollution control measures from 2016 to 2018,the acid rain pollution in this city has *** order to understand the recent situation,a comprehensive study on the acid rain was carried out from January 2011 to December *** pH values during the study period varied from 3.3 to 7.5,with a volume-weighted mean value of *** predominant acidic components of the precipitation were SO_(4)^(2-)and NO_(3)^(-),accounting for 89.3% of the total *** ratio of non-sea-salt SO_(4)^(2-)to NO_(3)^(-)showed a decreasing trend,revealing that the pollution type of acid rain changed from sulfuric acid type to sulfuric acid and nitric acid compound *** correlation analysis(p<0.05)showed that SO_(4)^(2-)was positively correlated with NH_(4)^(+),Ca^(2+),and Mg^(2+);hence,it predominated in precipitation as(NH_(4))_(2)SO_(4),NH_(4)HSO_(4),CaSO_(4),and MgSO_(4).Significant positive correlation of Ca^(2+)with Mg^(2+)shows that they may originated mainly from *** positive correlation between SO_(4)^(2-)and F^(-)and Cl^(-)indicate that their source may be related to the non-ferrous metal smelting industry in *** correlation analysis shows that emissions from the non-ferrous metal smelting industry in the area have a large significant on SO_(4)^(2-)and F^(-)in precipitation,while Cl^(-)may still be emitted from other anthropogenic sources.

关键词： Acid rain pH Chemical composition Neutralization factor Correlation analysis

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多模GNSS PPP时间传递性能比对分析

导航定位与授时 2024年第1期11卷 115-123页

作者：李佳豪贾小林杜彦君张智超严祥高卢文韬长安大学地质工程与测绘学院西安710061 西安测绘研究所西安710054 西安科技大学测绘科学与技术学院西安710054

精密单点定位(PPP)时间传递技术是国际时间比对的重要手段之一,为协调世界时的计算做出巨大贡献。为探究多系统融合PPP时间频率传递性能,选取3个国际授时实验室的测站数据组成2条链路,采用8种实验模式对比分析单系统、双系统、三系统和... 详细信息

精密单点定位(PPP)时间传递技术是国际时间比对的重要手段之一,为协调世界时的计算做出巨大贡献。为探究多系统融合PPP时间频率传递性能,选取3个国际授时实验室的测站数据组成2条链路,采用8种实验模式对比分析单系统、双系统、三系统和四系统PPP时间频率传递性能。实验结果表明:各多系统组合较单GPS系统在可见星数上均有较大提升,且极大改善了钟差精度因子,增加了时间比对结果的稳健性和可靠性。在时间传递稳定性方面:对于453.4 km的PTBB-BRUX链路,较单GPS系统,双系统中GPS/BDS组合提升效果最优,提升率约为10.39%,三系统中GPS/GLONASS/BDS组合提升率最优,约为11.86%,四系统组合提升率为11.98%,可从0.0467 ns提升至0.0411 ns;对于8031.8 km的PTBB-NIST链路,GPS/BDS组合提升率约为4.89%,GPS/GLONASS/BDS组合提升率约为5.49%,四系统组合提升率为5.79%,可从0.1140 ns提升至0.1074 ns。在频率传递稳定度方面:在前10000 s内双系统组合平均提升17.6%,三系统组合平均提升20.5%,四系统组合提升21.6%。

关键词：多系统精密单点定位时间传递频率传递时间稳定度

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