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工业化生产NG/TEGDN混合硝酸酯的硝化及洗涤过程研究
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作者 张小军 冯渐超 +1 位作者 何小民 王中合 《化学推进剂与高分子材料》 CAS 2019年第4期60-65,共6页
研究了混合硝酸酯硝化甘油(NG)/二缩三乙二醇二硝酸酯(TEGDN)生产工艺中的硝化及洗涤过程,通过硝化试验使硝酸酯溶损最小,最终可降到9%左右。优化硝化过程,保证混合硝酸酯和废酸的分离;通过对混合硝酸酯水溶性研究,确定洗涤参数,优化洗... 研究了混合硝酸酯硝化甘油(NG)/二缩三乙二醇二硝酸酯(TEGDN)生产工艺中的硝化及洗涤过程,通过硝化试验使硝酸酯溶损最小,最终可降到9%左右。优化硝化过程,保证混合硝酸酯和废酸的分离;通过对混合硝酸酯水溶性研究,确定洗涤参数,优化洗涤过程,使硝酸酯安定性满足要求;溶解在水中的混合硝酸酯可回收再利用。在国内首次采用相关工艺进行NG/TEGDN混合硝酸酯的安全生产。 展开更多
关键词 NG TEGDN 硝酸酯 硝化 洗涤 高能黏合剂
金匮肾气丸对糖尿病复合脑缺血模型大鼠认知功能障碍的影响及其机制研究 预览
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作者 王玲玉 谭涛 陈伟燕 《中国现代医生》 2019年第24期37-40,共4页
目的探讨金匮肾气丸对于糖尿病复合脑缺血模型大鼠认知功能的影响及其机制。方法将SD大鼠随机分为正常对照组和模型组。正常对照组用普通基础饲料饲养,模型组用高脂高糖饲料饲养,30 d后建立2型糖尿病胰岛素抵抗大鼠,对糖尿病大鼠施以双... 目的探讨金匮肾气丸对于糖尿病复合脑缺血模型大鼠认知功能的影响及其机制。方法将SD大鼠随机分为正常对照组和模型组。正常对照组用普通基础饲料饲养,模型组用高脂高糖饲料饲养,30 d后建立2型糖尿病胰岛素抵抗大鼠,对糖尿病大鼠施以双侧颈动脉缺血再灌手术诱导糖尿病脑病模型。将模型组大鼠随机分为糖尿病模型组、金匮肾气丸组及二甲双胍组,采用Morris水迷宫实验对动物行为学进行评价,处死大鼠后取脑海马组织,采用Western blot法检测各组大鼠海马神经元Ng和mGluR5蛋白表达情况。结果水迷宫实验结果显示,与糖尿病模型组比较,金匮肾气丸组及二甲双胍组大鼠逃避潜伏期和探索距离缩短(P<0.05或P<0.01),目标象限游泳时间显著延长,站台穿越次数显著增加(P<0.05);大鼠海马神经元中Ng和mGluR5蛋白表达恢复,并且呈剂量依赖性。结论金匮肾气丸可明显改善糖尿病脑病模型大鼠认知障碍,并增强其大脑海马区Ng和mGluR5蛋白表达。 展开更多
关键词 糖尿病脑病 金匮肾气丸 NG MGLUR5
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不孕症女性生殖道病原体感染临床分析 预览
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作者 谭文敏 李浩 《中国计划生育学杂志》 2019年第7期918-920,共3页
目的:探讨女性不孕症与生殖道衣原体(CT)、支原体(UU)、淋球菌(NG)病原体感染。方法:选择2016年2月—2017年12月本院接诊的女性不孕症患者125例(不孕组),其中输卵管性不孕61例,非输卵管性不孕64例;另选本院产前检查正常孕妇120例(对照组... 目的:探讨女性不孕症与生殖道衣原体(CT)、支原体(UU)、淋球菌(NG)病原体感染。方法:选择2016年2月—2017年12月本院接诊的女性不孕症患者125例(不孕组),其中输卵管性不孕61例,非输卵管性不孕64例;另选本院产前检查正常孕妇120例(对照组)。均行生殖道CT、UU、NG检测并分析与不孕症关系。结果:不孕组CT、UU、NG、CT+UU、CT+NG感染率(7.2%、31.2%、4.8%、4.0%、3.2%)均高于对照组(P<0.05),UU+NG交叉感染率与对照组无差异(P>0.05)。输卵管性不孕女性生殖道CT、UU、NG、CT+UU、CT+NG感染率(13.1%、49.2%、9.8%、8.2%、6.6%)均高于非输卵管性不孕女性(P<0.05),UU+NG交叉感染率与非输卵管性不孕组无差异(P>0.05)。CT、UU、NG、CT+UU、CT+NG、UU+NG感染与女性输卵管性不孕具有相关性(P<0.05)。结论:女性生殖道CT、UU、NG感染和交叉感染可增加女性不孕症的患病风险,尤其是交叉感染育龄期女性,临床应重视对女性不孕症患者上述指标检测。 展开更多
关键词 女性不孕症 生殖道感染 衣原体 支原体 淋球菌
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The Belt and Road Initiative from Three Theoretical Perspectives 预览
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作者 Fu Mengzi 《现代国际关系:英文版》 2019年第2期1-33,共33页
Efforts have generally been made from policy considerations to interpret reasons for the proposition of the Belt and Road Initiative and its global layout.Though they are of some significance,such a grand initiative c... Efforts have generally been made from policy considerations to interpret reasons for the proposition of the Belt and Road Initiative and its global layout.Though they are of some significance,such a grand initiative certainly has its own internal theoretical basis.This paper is in the opinion that the spillover effect of oversized economy,the extension of the value chain and its climbing effect,as well as channel suitability and location orientation constitute the endogenous driving forces of the Belt and Road Initiative.Each of the three theoretical perspectives has its own internal realistic basis,all of which may offer some reference that is conducive to understanding the practice and future development of the Belt and Road Initiative. 展开更多
关键词 the BELT and ROAD INITIATIVE ENDOGENOUS driving force theoretical BASIS in terconnection and interworki ng
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Nanotechnology based CRISPR/Cas9 system delivery for genome editing:Progress and prospect
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作者 Huan Deng Wei Huang Zhiping Zhang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第10期2437-2450,共14页
The genome editing tool,clustered regularly interspaced short palindromic repeats(CRISPR)/Cas9 system,has achieved successful therapeutic efficacy via precise modification of the genome and exceeded previous genome en... The genome editing tool,clustered regularly interspaced short palindromic repeats(CRISPR)/Cas9 system,has achieved successful therapeutic efficacy via precise modification of the genome and exceeded previous genome engineering methods owing to its versatility and simplicity.Rapid expansion in biomedical research has benefited from this newly emerged technique,such as genetic diseases treatment,cancer characterization,and plant improvement.However,the key challenge is efficient delivery of CRISPR components in vivo and nanotechnology plays an in dispensable role in non viral gene delivery.In this review,we will first briefly describe the mechanism and delivery strategies of CRISPR/Cas9 system.Furthermore,the past and current researches of nan oparticles based CRISPR/Cas9 system delivery for genome editi ng will be highlighted.Fin ally,we will discuss the challe nges and prospects of CRISPR/Cas9 system combi ned with nano tech no logy for clinical translation in the future. 展开更多
关键词 clustered regularly in terspaced short palindromic repeats(CRISPR)/Cas9 GENOME editi ng nan oparticle polymer LIPOSOME
Boosting the rate capability of multichannel porous TiCh nanofibers with well-dispersed Cu nanodots and Cu^2+-doping derived oxygen vacancies for sodium-ion batteries
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作者 Ying Wu Zengxi Wei +4 位作者 Rui Xu Yue Gong Lin Gu Jianmin Ma Yan Yu 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第9期2211-2217,共7页
The use of TiO2 as an anode in rechargeable sodium-ion batteries(NIBs)is hampered by intrinsic low electronic conductivity of TiO2 and in ferior electrode kinetics.Here,a high-performa nee T1O2 electrode for NIBs is p... The use of TiO2 as an anode in rechargeable sodium-ion batteries(NIBs)is hampered by intrinsic low electronic conductivity of TiO2 and in ferior electrode kinetics.Here,a high-performa nee T1O2 electrode for NIBs is prese nted by desig ning a multicha rinel porous T1O2 nano fibers with well-dispersed Cu nan odots and Cu^2+-doping derived oxyge n vaca ncies(Cu-MPTO).The in-situ grow n well-dispersed copper nano dots of about 3 nm on TiO2 surface could significantly enhance electronic conductivity of the TiO2 fibers.The one-dimensional multichannel porous structure could facilitate the electrolyte to soak in,leadi ng to short tran sport path of Na^+through carb on toward the TiO2 nano particle.The Cu^2+-doping induced oxygen vacancies could decrease the bandgap of T1O2,resulting in easy electron trapping.With this strategy,the Cu-MPTO electrodes render an outstanding rate performance for NIBs(120 mAh·g^-1 at 20 C)and a superior cycling stability for ultralong cycle life(120 mAh·g^-1 at 20 C and 96.5%retention over 2,000 cycles).Density functional theory(DFT)calculations also suggest that Cu^2+doping can enhance the conductivity and electron transfer of T1O2 and lower the sodiation energy barrier.This strategy is confirmed to be a general process and could be extended to improve the performance of other materials with low electronic conductivity applied in energy storage systems. 展开更多
关键词 multicha nnel POROUS T1O2 NANO fibers CU NANO dots Cu^2+dopi ng SODIUM ion batteries density functional theory(DFT)calculati ons
Treatment of Common Technical Problems in Roof Construction 预览
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作者 Guirong Ding Xi Chen Jiangbo Du 《建筑与设计评论》 2019年第1期21-30,共10页
Roof waterproof engineering is an important part of architectural engineering,waterproof engineering quality is good or bad,a direct impact on the life of buildings and structures,affecting people’s normal life order... Roof waterproof engineering is an important part of architectural engineering,waterproof engineering quality is good or bad,a direct impact on the life of buildings and structures,affecting people’s normal life order.“The Construction Engineering Quality Management Ordinance”provides for the roof waterproof engineering warranty period of 5 years,showing that the quality of roofing works is an important part of the civil housing construction.Its main role is to meet the user on the housing drainage,waterproofing,heat insulation,thermal insulation requirements.Roof cannot have leakage and water phenomenon,while the roof should also make the roof after the landscaping function.Roof construction quality is good or bad,the pros and cons are related to the life of the building.If the roof of water leakage,water seepage,people will bring a lot of inconvenience to life,not only cause serious economic losses,but also directly affect the people's normal life.So to ensure the quality of roof engineering,design is the premise,the material is the foundation,construction is the key,and maintenance management is guaranteed.Only the strict material off,well-designed,carefully construction,in order to ensure the quality of roofi ng works in order to give users to create a good living or working environment. 展开更多
关键词 ROOF engineering waterproofi NG PROJECT THERMAL INSULATION PROJECT
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燃气梭式窑高温系数的探究
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作者 郭小军 谢骁斐 +1 位作者 韦祎 陈旗 《工业炉》 2019年第4期55-57,共3页
高温系数是窑炉设计过程中的一个基本参数,在燃料品种确定的前提下,可以通过高温系数和燃料的理论燃烧温度的计算来确定最高炉温是否可以满足生产要求。高温系数没有可用的计算公式,一般按经验选取。本文通过理论计算并与燃气梭式窑的... 高温系数是窑炉设计过程中的一个基本参数,在燃料品种确定的前提下,可以通过高温系数和燃料的理论燃烧温度的计算来确定最高炉温是否可以满足生产要求。高温系数没有可用的计算公式,一般按经验选取。本文通过理论计算并与燃气梭式窑的实际运行数据进行了对比,提出燃气梭式窑高温系数可以提高到0.9,并详细分析了导致高温系数升高的原因。 展开更多
关键词 燃气梭式窑 高温系数 液化石油气 天然气
医学生生涯规划课程教学效果评价研究
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作者 张丽莉 邱蔚六 +5 位作者 周曾同 刘艳 姚敏 阮昊珏 王怡 吴皓 《中华医学教育探索杂志》 2019年第5期442-444,共3页
目的 通过问卷调查和访谈评价医学生生涯规划课程教学效果。方法 选择2017、2018届参与生涯规划课堂的临床医学专业医学生54人为研究对象。授课前后,通过问卷调查和访谈方法测试其生涯成熟度指标,以评价课程效果。调查结果使用SPSS 15.... 目的 通过问卷调查和访谈评价医学生生涯规划课程教学效果。方法 选择2017、2018届参与生涯规划课堂的临床医学专业医学生54人为研究对象。授课前后,通过问卷调查和访谈方法测试其生涯成熟度指标,以评价课程效果。调查结果使用SPSS 15.0进行t检验。结果 授课后医学生在自我认知、职业认知、信息应用、个人调适、职业态度5个方面的生涯成熟度评分均高于授课前。且在信息应用维度,授课前后医学生生涯成熟度测评成绩分别为(3.71±0.99)分、(4.01±0.93)分,差异有统计学意义(P=0.015);其他维度比较差异无统计学意义。在自我认知、职业认知、个人调试、职业态度4个维度,男生得分高于女生;在信息应用维度,女生得分高于男生。男生与女生比较,职业态度维度差异具有统计学意义(P<0.05)。结论 医学生生涯规划课程对医学生职业发展具有帮助和启示,但部分授课内容仍需优化和改进。 展开更多
关键词 医学生 生涯规划 生涯成熟度 教学效果
资讯
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《军事文摘》 2019年第3期4-5,共2页
印度尼西亚军方升级直升机机队据《飞行国际》2019年1月11日报道,印度尼西亚已经增购了8架空客直升机H255,与另外9架贝尔412EPI一起,将由空军用于战斗搜索和救援任务。这些直升机将在万隆厂重新组装并加装任务系统,由空客直升机公司在... 印度尼西亚军方升级直升机机队据《飞行国际》2019年1月11日报道,印度尼西亚已经增购了8架空客直升机H255,与另外9架贝尔412EPI一起,将由空军用于战斗搜索和救援任务。这些直升机将在万隆厂重新组装并加装任务系统,由空客直升机公司在印尼当地的合作伙伴PT Dirgantara Indonesia公司交付。H225是一款具有实战能力的直升机,被全世界的军事客户所认可。 展开更多
关键词 水下无人潜航器 NG 美国陆军 直升机公司 闪电战斗机 英国皇家海军 威奇托 伊丽莎白女王 RBS 巴布科克 波塞冬 特朗普 铀浓缩 俄罗斯
天然气储配站罐区的重大危险源识别与风险控制 预览
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作者 魏彬 苏长远 《上海煤气》 2019年第4期17-21,共5页
基于重大危险源评价方法,分析天然气储配站储罐区的固有危险性和危险抵消因素,对重大危险源进行风险分析和评价,最终得出储气区的危险等级为4级,控制能力等级为C级,控制能力和危险等级相匹配,储气区的安全风险可控的结论。提出管理措施... 基于重大危险源评价方法,分析天然气储配站储罐区的固有危险性和危险抵消因素,对重大危险源进行风险分析和评价,最终得出储气区的危险等级为4级,控制能力等级为C级,控制能力和危险等级相匹配,储气区的安全风险可控的结论。提出管理措施和建议,为今后类似的储配站的建设、维护管理等有借鉴意义。 展开更多
关键词 天然气 储配站 重大危险源 风险辨识 风险控制
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Twelve-week study of moxa smoke:occupational exposure in female rats
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作者 Han Li Huang Chang +15 位作者 Yang Jia Wang Lei Bai Hua Liu Juntian Jian Huang Liu Ping Lim MinYee Ju Dahong Lao Lixing Liu Changxi Zhao Baixiao Sun Wen Xu Anping Yang Xiuyan Zhang Cong He Rui 《中医杂志:英文版》 SCIE CAS CSCD 2019年第2期207-212,共6页
OBJECTIVE: To assess the toxicity of moxa smoke in rats.METHODS: Forty-eight female Wister rats were randomly divided into 4 groups(n = 12/group) to simulate moxa smoke exposure in Chinese medicine clinics(CMCs): the ... OBJECTIVE: To assess the toxicity of moxa smoke in rats.METHODS: Forty-eight female Wister rats were randomly divided into 4 groups(n = 12/group) to simulate moxa smoke exposure in Chinese medicine clinics(CMCs): the control group, and three moxa-smoke exposed groups of PM10 mass concentrations 3-5, 7-9 and 27-30 mg/m~3, respectively.These concentrations were 1 ×, 2-3 ×, and 7-9 ×fold the concentrations found in CMCs. Exposures continued for 12 weeks(200 min/d, 5 d/week).RESULTS: No deaths were noted. After the exposure, the body weights, ratios of organ weight to body weight, urinary parameters, hematological parameters, clinical chemistry parameters and microscopic examinations revealed no obvious toxicity.CONCLUSION: Moxa smoke did not induce toxic effects in female rats in the study. These findings provide new evidence to the toxicity of moxa smoke. 展开更多
关键词 MOXIBUSTION ARTEMISIA Smoki ng non-tobacco products TOXICITY tests
Technical and Economic Aspects and Experience from 6 Years of Operating the Technology Using the Waste Heat from the Exhaust Gases of Heat Sources and 3 Years of Operating a Heating Plant in an Autonomous, Island Regime 预览
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作者 Imrich Discantiny 《地质资源与工程:英文版》 2019年第2期39-44,共6页
This article is focused on technical and economic evaluation of more than 6-years experiences of operating the Waste Heat Recovery technology—the manner and system of flue gas processing generated in the combustion p... This article is focused on technical and economic evaluation of more than 6-years experiences of operating the Waste Heat Recovery technology—the manner and system of flue gas processing generated in the combustion process in heat & power plants, cogeneration units, etc., which burn the gaseous fuel, primarily natural gas, or methane, biogas, geothermal gas, or other gaseous mixtures containing hydrogen. The solution proposes a more effective and non-traditional use of gaseous fuel for heating, the flue gases of which are processed in order to extract additional utilisable heat, with potential elimination of CO2 from them. Deploying of the heating plant in an island regime (OFF-GRID) enables definition of the benefits brought by the 3 years of operational experience and presents visions for the future offering the possibility to utilise the support energy services at the municipal as well as regional level. 展开更多
关键词 NATURAL GAS (NG) liquefied NATURAL GAS (LNG) liquefied propane GAS (LPG) combined HEAT & power (CHP) renewable energy sources (RES) waste HEAT recovery (WHR) international GAS union (IGU)
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Highly efficient and selective CO2 electro-reduction with atomic Fe-C-N hybrid coordination on porous carbon nematosphere
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作者 Haixia Zhong Fanlu Meng +2 位作者 Qi Zhang Kaihua Liu Xinbo Zhang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第9期2318-2323,共6页
Carbon dioxide reduction(CO2RR)has become a promising way to address the energy and environmental crisis,of which the fundamental development of the optimal electrocatalysts is the crucial part.Herein,we develop Fe an... Carbon dioxide reduction(CO2RR)has become a promising way to address the energy and environmental crisis,of which the fundamental development of the optimal electrocatalysts is the crucial part.Herein,we develop Fe and N doping porous carb on n ematosphere(FeNPCN)as an excellent CO2RR electrocatalyst in aqueous electrolyte.Featuring with the high conductivity,pore structure and abundant Fe and N doping,FeNPCN exhibits high catalytic activity with a high faradaic selectivity of CO(94%)and long-term durability.Moreover,the ratio of CO and H2 can be changed by the applied potential for the different syngas related industry.Density functional theory(DFT)calculation results also reveal that the excellent catalytic activity is likely attributed to C and N hybrid coordination with atomic Fe. 展开更多
关键词 CARBON dioxide reducti on ELECTROCATALYSIS porous CARBON carb on MON oxide metal/nitrogen dopi ng
Heavy cigarette smoking and alcohol consumption are associated with impaired sperm parameters in primary infertile men
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作者 Luca Boeri Paolo Capogrosso +7 位作者 Eugenio Ventimiglia Filippo Pederzoli Walter Cazzaniga Francesco Chierigo Federico Deho Emanuele Montanari Francesco Montorsi Andrea Salonia 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第5期478-485,共8页
We assessed the concomitant impact of cigarette smoking and alcohol con sumption in men presenting for primary couple's infertility.Data from 189 in fertile men were an a lyzed.Semen analysis,serum hormones,and sp... We assessed the concomitant impact of cigarette smoking and alcohol con sumption in men presenting for primary couple's infertility.Data from 189 in fertile men were an a lyzed.Semen analysis,serum hormones,and sperm DNA fragmentation(SDF)were obtained.Smoking status was categorized as follows:current nonsmoker(-S),moderate smoker(+MS),and heavy smoker(+HS).Alcohol consumption was categorized as follows:abstainer(-D),moderate drinker(+MD),and heavy drinker(+HD).Descriptive statistics and logistic regression models were applied.Among all the participants,132(69.8%),30(15.9%),and 27(14.3%)patients were-S,+MS,and+HS,respectively.In addition,67(35.4%),77(40.7%)and 45(23.8%)men were-D,+MD and+HD,respectively.Regarding concomitant habits,52(27.5%)patients were nonsmokers and abstainers(-S/-D:Group 1),91(48.1%)had at least one recreational habit(-S/+D or+S/-D:Group 2),and 46(24.3%)were both smokers and drinkers(+S/+D:Group 3).Sperm concentration and progressive motility were lower in+HS and+HD,compared with-S and-D(all P<0.05),respectively.Similarly,both parameters were significantly lower in Group 3 than Groups 1 and 2(all P<0.05).SDF values were higher in Group 3 than Groups 1 and 2(both P<0.05).In multivariate analysis,follicle-stimulating hormone(FSH)levels and concomitant+S/+D status were independent predictors of impaired sperm concentration and progressive motility(all P<0.05).Heavy smoking and heavy drinking were associated with worse seminal parameters than moderate smoking/drinking and nonsmoking/abstaining.When concomitant,+S/+D status has an even greater detrimental effect on semen parameters. 展开更多
关键词 ALCOHOL CON SUMPTION CIGARETTE smoki ng in FERTILITY risk factors seme n an alysis
点燃式NG发动机燃烧系统优化研究 预览
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作者 刘道君 秦磊 孙霞 《重型汽车》 2019年第1期8-10,共3页
在开发某款天然气发动机的过程中,发动机出现了进气回火、排气放炮等性能不稳定现象。借助CFD软件模拟缸内流动与燃烧,对燃烧室进行了优化设计,对比了新旧两种燃烧室内混合气燃烧和流动情况,分析造成两种燃烧室内燃烧差异的原因。通过... 在开发某款天然气发动机的过程中,发动机出现了进气回火、排气放炮等性能不稳定现象。借助CFD软件模拟缸内流动与燃烧,对燃烧室进行了优化设计,对比了新旧两种燃烧室内混合气燃烧和流动情况,分析造成两种燃烧室内燃烧差异的原因。通过分析对比湍动能、火焰传播与形成过程的差异诠释了原燃烧室产生回火放炮的原因。新开发的燃烧室不仅有效解决了进气回火、排气放炮问题,还使发动机的扭矩、功率比原来有所提高,同时燃料消耗率显著降低。 展开更多
关键词 发动机 燃烧室内 湍动能 火焰传播 燃烧系统 NG
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渤海南部垦利6-6构造东二下段、馆陶组砂岩碎屑锆石定年及物源示踪 预览
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作者 赵梦 庞小军 +2 位作者 金小燕 冯冲 王茂桢 《中国海上油气》 CAS CSCD 北大核心 2019年第6期52-59,共8页
为了示踪渤海南部垦利6-6构造东二下段、馆陶组砂岩沉积,对KL6-6-A井的东二下段、馆陶组2个砂岩岩屑样品进行了碎屑锆石U-Pb定年和锆石阴极发光(CL)图像分析。研究测得211个谐和年龄点,发现KL6-6-A井东二下段、馆陶组砂岩样品中白垩纪... 为了示踪渤海南部垦利6-6构造东二下段、馆陶组砂岩沉积,对KL6-6-A井的东二下段、馆陶组2个砂岩岩屑样品进行了碎屑锆石U-Pb定年和锆石阴极发光(CL)图像分析。研究测得211个谐和年龄点,发现KL6-6-A井东二下段、馆陶组砂岩样品中白垩纪锆石含量分别为27.6%和30.5%,并都具有114 Ma主峰值和约2500 Ma的次要峰值年龄;锆石以100~200μm的长柱状、短柱状晶体为主,岩浆生长振荡环带发育,具有明显的核-边结构,晶体边缘均呈棱角状,破碎晶体断边明显。因此,认为KL6-6-A井的东二下段、馆陶组砂岩为近源沉积,母岩为相邻的中生界白垩系青山组基底,当时并未拓展至胶北地区、蓬莱长岛地区、龙口屺坶岛地区等陆上地区。 展开更多
关键词 渤海南部 垦利6-6构造 东二下段 馆陶组 碎屑锆石定年 物源示踪
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神奇动物在哪里
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作者 兔儿果 《新少年》 2019年第11期26-29,共4页
嘿,丁满!在非洲的草原或开阔平原地区,如果你大喊一声“嘿,丁满”,能唱着“哈库纳,玛塔塔”快乐回应的,便是我们本期的主人公狐獴(meng)了。狐獴,也被人们叫作猫鼬(you),小小的,萌萌的,关于它们的故事真不少。
关键词 玛塔 ng) 快乐
汉、越味觉词“甜”与“Ngot”的隐喻意义比较 预览
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作者 陈氏航 《现代语文》 2019年第9期91-97,共7页
在总结相关的理论基础上,采取统计、对比等方法,对现代汉语与越南语味觉词“甜”和“Ngot”的隐喻意义进行考察与分析,阐明其各自特点,并比较两者的异同。研究发现,汉、越语中“甜”的隐喻投射有12种,其中,7种为汉、越所共有,2种为汉语... 在总结相关的理论基础上,采取统计、对比等方法,对现代汉语与越南语味觉词“甜”和“Ngot”的隐喻意义进行考察与分析,阐明其各自特点,并比较两者的异同。研究发现,汉、越语中“甜”的隐喻投射有12种,其中,7种为汉、越所共有,2种为汉语所特有,3种为越语所特有,表现出同异共存的关系。 展开更多
关键词 “甜” ngot” 味觉词 隐喻 汉越对比
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GAP对NG分子间相互作用及CMDB推进剂感度的影响 预览
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作者 张正中 蔚红建 +2 位作者 唐秋凡 齐晓飞 屈蓓 《火炸药学报》 CSCD 北大核心 2018年第2期173-177,共5页
通过构建NG、GAP及GAPjNG共混体系模型,采用分子动力学模拟方法,对GAPjNG体系分子间作用力、分子间径向分布函数及ONOz键长分布变化进行了分析;分别用理论和实验方法研究了GAP对NG分子间相互作用和CMDB推进剂机械感度的影响。结果表... 通过构建NG、GAP及GAPjNG共混体系模型,采用分子动力学模拟方法,对GAPjNG体系分子间作用力、分子间径向分布函数及ONOz键长分布变化进行了分析;分别用理论和实验方法研究了GAP对NG分子间相互作用和CMDB推进剂机械感度的影响。结果表明,在GAP存在条件下,NG分子间作用力明显减弱,从而减小了受外界刺激时NG分子间的内摩擦;GAP塑化后使整个体系产生明显的黏弹性,可以在NG体系受到冲击作用时起到一定缓冲作用;GAP使NG分子中ONO。的平均键长和最大键长分别从1.74nm 和1.77nm,降低至1.65nm和1.71nm,从而使0NOz健在受到外界刺激时更难断裂;添加质量分数3%GAP的HMX-CMDB推进剂的撞击感度Hs。由18.5cm.提高至30.2cm,摩擦感度P由76%降至52%,表明GAP可以有效降低CMDB推进剂的机械感度。 展开更多
关键词 NG GAP 分子间相互作用 径向分布函数 键长 分子动力学 CMDB推进剂
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