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炼钢天车车轮轴断裂原因分析

金属制品 2024年第3期50卷 52-55页

作者：马昂昂柯炜李桂英王一帆青岛特殊钢铁有限公司质量检测所山东青岛266049

炼钢天车车轮轴运行过程中断裂。对车轮轴断裂进行失效分析。结果表明:车轮轴由45钢而非40Cr钢制成,断口磨损严重,通过电镜观察有韧窝特征,为韧性断裂,车轮轴基体组织为珠光体+铁素体,没有经过热处理,因为车轮轴未按规定使用材料,未经... 详细信息

炼钢天车车轮轴运行过程中断裂。对车轮轴断裂进行失效分析。结果表明:车轮轴由45钢而非40Cr钢制成,断口磨损严重,通过电镜观察有韧窝特征,为韧性断裂,车轮轴基体组织为珠光体+铁素体,没有经过热处理,因为车轮轴未按规定使用材料,未经调质处理,力学性能较低,从而导致断裂。

关键词： 40Cr 车轮轴断裂失效分析力学性能

Higher Body Temperatures and Earlier Parturition in Response to Hypoxia Experienced by Pregnant Lizards

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Asian Herpetological Research 2021年第2期12卷 228-233页

作者： Zhongwen JIang Liang ma Shi'ang Tao Xingzhi Han Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Princeton School of Public arui International Affairs Princeton UniversityPrincetonNew Jersey 08544USA College of Chemistry and Life Sciences Zhejiang Normal UniversityJinhua 321004ZhejiangChina College of Wildlife and Protected Area Northeast Forestry UniversityHarbin 150040HeilongjiangChina

many species are shifting towards higher altitudes in response to global wa rming, but how these upslope-shifting species will respond to hypoxic environments at high altitudes remains unclear. Hypoxia can be especially challenging for viviparous reproduction because of the limitation of oxygen supply to the female and her developing embryos. To investigate the effect of hypoxia on viviparous females and their offspring we acclimated pregnant females of a high-altitude dwelling vivipa rous liza rd(Phr ynocephalus vlangalii) to local oxygen and hypoxia conditions, respectively. We then recorded maternal body temperatures, postpartum body condition, as well as offspring morphology and locomotor performance. We found that pregnant females had higher body temperatures and advanced their parturition under hypoxic acclimation. However, maternal body condition, offspring morphology and locomotor performance were unaffected by the hypoxic conditions during gestation. Our study suggests that upslope-shifting viviparous lizards respond to hypoxic environments by plastically adjusting their body tempera tures to reduce parturition time, without short-term costs to offspring traits.

关键词： climate change hypoxia offspring pregnant female reproduction viviparous lizard

儿童肱骨髁上骨折的多层螺旋CT后处理诊断研究

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中国城乡企业卫生 2024年第6期39卷 11-13页

作者：孙大昂马红丽滕州市中心人民医院小儿外科山东滕州277599 山东省滕州市中心人民医院影像中心

目的分析儿童肱骨髁上骨折的多层螺旋CT后处理的诊断效果,为儿童肱骨髁上骨折的诊断提供参考。方法选取2021年1月—2022年12月滕州市中心人民医院收治的60例儿童肱骨髁上骨折患儿为研究对象,患儿均进行多层螺旋CT平扫和CT后处理,分析两... 详细信息

目的分析儿童肱骨髁上骨折的多层螺旋CT后处理的诊断效果,为儿童肱骨髁上骨折的诊断提供参考。方法选取2021年1月—2022年12月滕州市中心人民医院收治的60例儿童肱骨髁上骨折患儿为研究对象,患儿均进行多层螺旋CT平扫和CT后处理,分析两种方法图像特点,并对比两种诊断效能。结果多层螺旋CT后处理技术的灵敏度、特异度、准确度为98.33%、98.33%及100.00%,均高于多层螺旋CT平扫的86.67%、83.33%及88.33%,差异均有统计学意义(χ^(2)=4.324、6.405、5.461,P10°~15°的患儿22例、占36.67%。结论运用多层螺旋CT后处理技术诊断儿童肱骨髁上骨折优势明显,可更加准确、多角度地显示肱骨髁上骨折情况,明显提高患儿骨折诊断的准确性,具有较高的临床应用价值。

关键词：儿童肱骨髁上骨折多层螺旋CT后处理诊断效果

Effects of osmotic stress on the expression profiling of aquaporin genes in the roughskin sculpin(Trachidermus fasciatus)

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Acta Oceanologica Sinica 2020年第6期39卷 19-25页

作者： Qian ma Xinfu Liu ang Li Shufang Liu Zhimeng Zhuang College of Fisheries Guangdong Ocean UniversityZhanjiang 524088China Yellow Sea Fisheries Research Institute Chinese Academy of Fishery SciencesQingdao 266071China

Aquaporins(AQPs)are a family of integral membrane proteins that have been shown to be important for osmoregulation in many *** identify potential stress resistance-related aqp genes in salinity adaptation of the roughskin sculpin Trachidermus fasciatus,we investigated the time-course expression dynamics of seven aquaporin genes(aqp1,4,7,8,10,11 and 12)in three osmoregulatory tissues(kidney,gill and intestine)and one metabolic tissue(liver).The fish were subjected to two different acute osmotic treatments(seawater-tofreshwater transfer respectively achieved in 1 h and 24 h,namely,E-acute and acute group).The expression profiling of the seven aqp genes were performed using quantitative real-time PCR(qRT-PCR).At the time of all sampling time points(0 h,12 h,24 h and 48 h),no expression of aqp4 was found in the gill,liver and intestine;no expression of aqp7 was found in the gill and *** differences of aqp expression were determined in the four target tissues,and the mRNA levels were largely variable among gene members and *** patterns of the time-course expression were detected in most of the aqp genes in *** between the two acute groups,except that only one gene(aqp12)in the kidney and three genes(aqp7,aqp8 and aqp10)in the intestine revealed different expression *** results suggest that the expression response of aqp genes was similar under osmotic changes with different rates.

关键词： Trachidermus fasciatus aquaporin salinity changes stress response gene expression

Self-assembled nanochaperones enable the disaggregation of amyloid insulin fibrils

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Science China Chemistry 2022年第2期65卷 353-362页

作者： Hui Wang ang Li Menglin Yang Yu Zhao Linqi Shi Rujiang ma Key Laboratory of Functional Polymer materials of Ministry of Education Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China State Key Laboratory of Medicinal Chemical Biology Nankai UniversityTianjin 300071China

The deposition of highly ordered amyloid fibrils is recognized as a hallmark of amyloidosis diseases such as Alzheimer’s disease and Parkinson’s *** the amyloid fibrils is considered as one of the effective strategies for the control and treatment of amyloidosis *** this article,by simulating the function of natural molecular chaperones,co-assembled block copolymer micelles with coordination groups of nitrilotriacetic acid(NTA)and hydrophobic microdomains of poly(Nisopropylacrylamide)(PNIPAM)on the surface were used as nanochaperones(n Chaps)to disaggregate amyloid insulin *** ions chelated by NTA can bind the histidine imidazole residues while the PNIPAM microdomains can interact with the exposed hydrophobic sites on the amyloid insulin fibrils,which synergistically perturb the stability of amyloid insulin fibrils,loosen their structure,and finally promote their disaggregation.A combination of characterizations with fluorescence spectroscopy,transmission electron microscopy(TEM),dynamic hight scattering(DLS),and quartz crystal microbalance(QCM)demonstrated that mature amyloid insulin fibrils were completely disaggregated after incubating with n Chaps for 90 *** study may provide a promising strategy for the development of n Chaps for the treatment of amyloidosis diseases.

关键词： amyloid fibrils insulin nanochaperones disaggregation

额尔齐斯杂岩碎屑锆石U-Pb年龄及其对阿尔泰和东准噶尔地体拼合时限的制约

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地质通报 2024年第6期43卷 1032-1046页

作者：李昂徐严韩宝福廖闻造山带与地壳演化教育部重点实验室北京大学地球与空间科学学院北京100871

额尔齐斯杂岩位于新疆北部的阿尔泰和东准噶尔地体之间,经历了强烈的变质变形作用,记录了2个地体的构造拼合事件。为约束阿尔泰和东准噶尔地体的拼合时限,通过碎屑锆石U-Pb年龄分析探讨沉积物源。从变碎屑岩样品中获得最年轻的碎屑锆石... 详细信息

额尔齐斯杂岩位于新疆北部的阿尔泰和东准噶尔地体之间,经历了强烈的变质变形作用,记录了2个地体的构造拼合事件。为约束阿尔泰和东准噶尔地体的拼合时限,通过碎屑锆石U-Pb年龄分析探讨沉积物源。从变碎屑岩样品中获得最年轻的碎屑锆石年龄为354 ma。在综合分析新的和已发表的碎屑锆石和区域构造年代学资料后,认为在额尔齐斯杂岩中,除同时以阿尔泰和东准噶尔地体为物源和以东准噶尔地体为单一物源的2类晚石炭世同碰撞沉积外,还可能包括较早以阿尔泰地体为单一物源的被动陆缘沉积,表明额尔齐斯杂岩形成时,阿尔泰和东准噶尔地体已经拼合。

关键词：额尔齐斯杂岩变碎屑岩物源分析碎屑锆石

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纳米硅补强氟橡胶的研究

橡胶工业 2024年第1期71卷 11-18页

作者：马玉聪王天骄郑顺奇丁昂吴爱民黄昊大连理工大学材料科学与工程学院辽宁大连116024 宁波泰科威橡胶科技有限公司浙江宁波315040 宁波星箭航天机械有限公司浙江宁波315153

以热弧等离子体法制备高纯度纳米硅,通过机械共混法制备炭黑/氟橡胶(FKM-C)和纳米硅/氟橡胶(FKMSi)复合材料,与不加填料的纯氟橡胶(P-FKM)复合材料相比,研究填料对氟橡胶性能的影响。结果表明:FKM-Si复合材料的脆性温度低于P-FKM复合材... 详细信息

以热弧等离子体法制备高纯度纳米硅,通过机械共混法制备炭黑/氟橡胶(FKM-C)和纳米硅/氟橡胶(FKMSi)复合材料,与不加填料的纯氟橡胶(P-FKM)复合材料相比,研究填料对氟橡胶性能的影响。结果表明:FKM-Si复合材料的脆性温度低于P-FKM复合材料;FKM-Si复合材料的硬度、拉伸强度和拉断伸长率均高于FKM-C复合材料,分别达到70度、12.16 MPa和289%;FKM-Si复合材料的截面无缺陷,说明纳米硅与氟橡胶的相容性好;FKM-Si复合材料的热稳定性比FKM-C复合材料好。

关键词：纳米硅氟橡胶复合材料低温脆性热稳定性

Systematical strategies for wastewater treatment and the generated wastes and greenhouse gases in China

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Frontiers of Environmental Science & Engineering 2012年第2期6卷 271-279页

作者： Jingbo GUO Fang ma Yuanyuan QU ang LI Liang Wang School of Civil Engineering Northeast Dianli UniversityJilin 132012China State Key Laboratory of Urban Water Resource and Environment School of Municipal and Environmental EngineeringHarbin Institute of TechnologyHarbin 150090China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China Vanillin Factory Jilin Petrochemical CompanyChina National Petroleum CorporationJilin 132021China

China now faces double challenges of water resources shortage and severe water pollution. To resolve Chinese water pollution problems and reduce its impacts on human health, economic growth and social develop- ment, the situation of wastewater treatment was investi- gated. Excess sludge and greenhouse gases （GHGs） emitted during wastewater treatment were also surveyed. It is concluded that Chinese water pollution problems should be systematically resolved with inclusion of wastewater and the solid waste and GHGs generated during wastewater treatment. Strategies proposed for the wastewater treatment in China herein were also adequate for other countries, especially for the developing countries with similar economic conditions to China.

关键词： wastewater treatment solid waste greenhousegases systematical strategies

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综述影响蜜蜂蜂群发展的因素

蜜蜂杂志 2024年第4期44卷 1-5页

作者：张俊黄廷悦马振刚农业农村部长江上游传粉昆虫资源保护与利用重点实验室重庆师范大学重庆市媒介昆虫重点实验室重庆师范大学

蜜蜂作为自然界喜群居的资源昆虫，是重要的传粉昆虫之一。其不仅能够提升农作物的产量和品质，还有利于维持生物多样性和生态系统的平衡。但是，近年来由于气候变化、栖息地丧失、病原体侵害、农药污染等诸多因素导致蜜蜂的数量呈现急... 详细信息

蜜蜂作为自然界喜群居的资源昆虫，是重要的传粉昆虫之一。其不仅能够提升农作物的产量和品质，还有利于维持生物多样性和生态系统的平衡。但是，近年来由于气候变化、栖息地丧失、病原体侵害、农药污染等诸多因素导致蜜蜂的数量呈现急剧下降的趋势。本文综述了能够影响蜜蜂蜂群发展的主要因素，从自然环境改变、化学环境影响、病原微生物与寄生虫的侵染、营养物质供应、饲料粒度、磁场和食物源的距离等方面具体展开，探讨各因素对蜜蜂蜂群发展的影响；以期提高人们对环境的保护意识，维护蜜蜂生存环境，以及为养蜂工作者进行蜜蜂健康养殖提供参考和借鉴。

关键词：蜜蜂影响因素蜂群发展