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Practice on Gravity-1 Rocket Dynamic Characteristics Design
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作者 BU Xiangwei SONG Yinghui HUANG Shuai 《Aerospace China》 2024年第1期9-17,共9页
Since the Dongfeng-2 missile, full-vehicle modal testing has been established as an indispensable part of the development and testing of rocket and missile models. However, as rockets have been developed larger, the c... Since the Dongfeng-2 missile, full-vehicle modal testing has been established as an indispensable part of the development and testing of rocket and missile models. However, as rockets have been developed larger, the cost and duration of such tests have significantly increased, magnifying their impact on model development. This article follows the process of the modal testing practice of the Gravity-1 rocket, reviewing and summarizing the design process of the rocket's dynamic characteristics. Initially, the article introduces common modeling techniques for launch rockets, including the mass-beam model and the hybrid element model. It then discusses the relationship between the structural dynamics model of the launch rocket and modal testing, aiming to reduce testing costs through refined structural dynamics modeling methods. Subsequently, the article describes the dynamic characteristics design process of the Gravity-1 carrier rocket, categorizes structural parameters, and studies how the selection of structural parameters affects the predicted dynamic characteristics of the rocket. Finally, it elaborates on the design of the modal testing scheme and the dynamic characteristics design based on the test data. 展开更多
关键词 Gravity-1 dynamic characteristics modal testing structural dynamics model
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NEW HETEROCYCLIC SYSTEMATIC SYNTHESIS V.THE SYNTHESIS AND CHARACTERISTICS OF 1,3a,5-TRISUBSTITUTED-3a,4,5,11-TETRAHYDRO-1,2,4-OXADIAZOLINO[5,4-d][1,5]BENZODIHETEROPINES
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作者 Hai Tao Wu Sheng JIN 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期95-96,共2页
Twenty-seven oxadiazolino[5,4-d][1,5]benzodiheteropine derivatives have been synthesized by the 1,3-dipolar cycloaddition of benzodiheteropines with nitrile oxide 1,3-dipoles,their conformations and the characteristic... Twenty-seven oxadiazolino[5,4-d][1,5]benzodiheteropine derivatives have been synthesized by the 1,3-dipolar cycloaddition of benzodiheteropines with nitrile oxide 1,3-dipoles,their conformations and the characteristics of the newly formed oxadiazoline fused on them have been studied.It has also been found that the mass spectra show characteristic fragmentation patterns. 展开更多
关键词 CI HZ BENZODIHETEROPINES NEW HETEROCYCLIC SYSTEMATIC SYNTHESIS V.THE SYNTHESIS AND characteristics OF 1 3a 5-TRISUBSTITUTED-3a 4 5 11-TETRAHYDRO-1 2 4-OXADIAZOLINO[5 4-d
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(1-3)-β-D葡聚糖联合降钙素原、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究
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作者 黄强 王宇 +5 位作者 江渊 梁道斌 黄锐洁 秦小超 潘燕妮 和鹰 《中国真菌学杂志》 CSCD 2024年第1期21-24,29,共5页
目的探讨(1-3)-β-D葡聚糖联合降钙素原(procalcitonin,PCT)、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究。方法回顾性选取我院2020年1月—2022年6月住院的120例艾滋病患者为研究对象。依据实验室结果,将... 目的探讨(1-3)-β-D葡聚糖联合降钙素原(procalcitonin,PCT)、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究。方法回顾性选取我院2020年1月—2022年6月住院的120例艾滋病患者为研究对象。依据实验室结果,将其分为马尔尼菲篮状菌感染确诊组(血或组织液培育养出马尔尼菲篮状菌),简称A组(62例),及马尔尼菲篮状菌感染临床诊断组[根据临床症状、体征、血常规及(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞多指标诊断],简称B组(58例)。检测患者(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞的表达水平,采用受试者工作特征(receiver-operating characteristic,ROC)曲线下面积(area under the curve,AUC)评估上述指标联合检测对艾滋病患者感染马尔尼菲篮状菌的诊断效能。结果A组的(1-3)-β-D葡聚糖和PCT水平均高于B组,CD4^(+)T淋巴细胞个数低于B组(P<0.05);(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞联合检测的AUC为0.933,(1-3)-β-D葡聚糖单独检测的AUC是0.812,PCT单独检测的AUC为0.883,CD4^(+)T淋巴细胞单独检测的AUC是0.810,(1-3)-β-D葡聚糖、PCT和CD4^(+)T淋巴细胞联合检测的AUC皆优于三项单独检测,表明(1-3)-β-D葡聚糖、PCT和CD4^(+)T淋巴细胞联合检测的诊断价值皆优于单一指标诊断,且联合检测的特异度、约登指数分别为92.43%和0.580,均高于三项单独检测。结论(1-3)-β-D葡聚糖联合PCT和CD4^(+)T淋巴细胞多指标对艾滋病马尔尼菲篮状菌感染具有非常高的临床诊断价值,能够帮助医生分析出高危风险患者,及时制定治疗方案,同时也承担预后效果的判断依据,对治疗艾滋病马尔尼菲篮状菌感染具有非常重要的研究价值。 展开更多
关键词 (1-3)-β-d葡聚糖 PCT CD4^(+)T淋巴细胞 艾滋病 马尔尼菲篮状菌感染
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血清SP-A、SP-D、HMGB1、KL-6、miR-21与老年急性加重特发性肺纤维化及肺功能的关系
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作者 李红 孙惠 王龙 《临床误诊误治》 CAS 2024年第20期26-30,共5页
目的 探讨血清表面活性蛋白-A(SP-A)、表面活性蛋白-D(SP-D)、高迁移率族蛋白B1(HMGB1)、涎液化糖链抗原-6(KL-6)、微小核糖核酸-21(miR-21)与老年急性加重特发性肺纤维化(AE-IPF)及肺功能的关系,以提高AE-IPF早期诊断率、防范误诊的发... 目的 探讨血清表面活性蛋白-A(SP-A)、表面活性蛋白-D(SP-D)、高迁移率族蛋白B1(HMGB1)、涎液化糖链抗原-6(KL-6)、微小核糖核酸-21(miR-21)与老年急性加重特发性肺纤维化(AE-IPF)及肺功能的关系,以提高AE-IPF早期诊断率、防范误诊的发生。方法 选取2023年1月至2024年1月收治的老年AE-IPF患者80例为AE-IPF组,另选择同期就诊的80例老年稳定特发性肺纤维化(IPF)患者为IPF组及50例体检健康老年人为对照组。比较3组血清SP-A、SP-D、HMGB1、KL-6、miR-21及肺功能指标[第1秒用力呼气容积(FEV1)、FEV1/用力肺活量(FVC)、第1秒用力呼气容积占预计值百分比(FEV1%pred)、1 min最大自主通气量(MVV)、1 min最大自主通气量占预计值百分比(MVV%pred)、肺一氧化碳弥散量占预计值百分比(DLCO%pred)]。分析血清SP-A、SP-D、HMGB1、KL-6、miR-21诊断AE-IPF的价值;分析血清SP-A、SP-D、HMGB1、KL-6、miR-21与肺功能指标的相关性。结果 IPF组、AE-IPF组血清SP-A、SP-D、HMGB1、KL-6、miR-21高于对照组,且AE-IPF组高于IPF组(P<0.05)。血清SP-A、SP-D、HMGB1、KL-6、miR-21诊断AE-IPF发生的曲线下面积分别为0.866、0.882、0.890、0.793、0.783,敏感度分别为0.800、0.825、0.800、0.763、0.813。AE-IPF组、IPF组FEV1、FEV1/FVC、FEV1%pred、MVV、MVV%pred、DLCO%pred均低于对照组,AE-IPF组低于IPF组(P<0.05)。血清SP-A、SP-D、HMGB1、KL-6、miR-21与FEV1、FEV1/FVC、FEV1%pred、MVV、MVV%pred、DLCO%pred均呈负相关(P<0.01)。结论 检测血清SP-A、SP-D、HMGB1、KL-6、miR-21表达情况可提高AE-IPF早期诊断率,防范误诊误治的发生。 展开更多
关键词 特发性肺纤维化 急性加重 表面活性蛋白-d 高迁移率族蛋白B1 1秒用力呼气容积 1 min最大自主通气量 肺一氧化碳弥散量
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食管癌术后重症肺炎患者血清肺表面活性物质相关蛋白质-D、高迁移率族蛋白B1和中性粒细胞与淋巴细胞比值水平变化及检测意义 被引量:1
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作者 张少锋 李丹青 +2 位作者 杜凡 魏志强 王海军 《陕西医学杂志》 CAS 2024年第8期1114-1117,1123,共5页
目的:探讨中性粒细胞与淋巴细胞比值(NLR)、肺表面活性物质相关蛋白质-D(SP-D)及高迁移率族蛋白B1(HMGB1)在食管癌术后重症肺炎(SP)患者中的水平变化及检测意义。方法:选取接受手术治疗的食管癌患者257例,根据手术治疗后是否发生SP将患... 目的:探讨中性粒细胞与淋巴细胞比值(NLR)、肺表面活性物质相关蛋白质-D(SP-D)及高迁移率族蛋白B1(HMGB1)在食管癌术后重症肺炎(SP)患者中的水平变化及检测意义。方法:选取接受手术治疗的食管癌患者257例,根据手术治疗后是否发生SP将患者分为SP组(124例)和对照组(133例)。比较两组血清SP-D、HMGB1和NLR水平。记录SP组患者28 d内预后情况,根据28 d内生存情况将SP组患者分为生存组(104例)和病死组(20例)。比较两组一般资料及实验室指标,采用Logistic回归分析食管癌术后SP患者预后影响因素。绘制受试者工作特征(ROC)曲线分析NLR、SP-D及HMGB1对食管癌术后SP患者28 d内病死风险的预测价值。结果:SP组血清SP-D及HMGB1和NLR水平高于对照组(均P<0.05)。病死组NLR、SP-D及HMGB1水平高于生存组(均P<0.05)。NLR、SP-D及HMGB1是食管癌术后SP患者病死的影响因素(均P<0.05)。NLR、SP-D及HMGB1预测食管癌术后SP患者28 d内病死风险的AUC分别为0.744、0.763、0.715,而三者联合检测的AUC更高(均P<0.05)。结论:食管癌术后SP患者NLR、SP-D及HMGB1水平升高,且与患者预后有关,三者联合检测有助于提升对患者病死风险的预测价值。 展开更多
关键词 食管癌 重症肺炎 中性粒细胞与淋巴细胞比值 肺表面活性物质相关蛋白质-d 高迁移率族蛋白B1 预后
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基于改进事件触发与1-D CNN的MMC冗余子模块开路故障实时诊断策略
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作者 庄凯 谢建峰 +2 位作者 罗辞勇 刘承鑫 顾亦超 《电工电能新技术》 CSCD 北大核心 2024年第11期55-67,共13页
在模块化多电平换流器(MMC)中存在大量的子模块(SM),其可靠性直接影响整个系统的安全稳定运行。本文引入了具有容错能力的新型冗余SM,并在此基础上提出了一种基于改进事件触发与一维卷积神经网络(1-D CNN)的MMC冗余SM开路故障实时诊断... 在模块化多电平换流器(MMC)中存在大量的子模块(SM),其可靠性直接影响整个系统的安全稳定运行。本文引入了具有容错能力的新型冗余SM,并在此基础上提出了一种基于改进事件触发与一维卷积神经网络(1-D CNN)的MMC冗余SM开路故障实时诊断策略。首先,选定MMC中特定SM构成的集成单元的电容电压作为事件触发对象,大大减少了传统诊断策略中需要观测的电容数量;其次,从有效地减少计算负担角度出发,改进事件触发流程,并结合1-D CNN算法有条件地对集成单元电容电压和桥臂电流波动情况分别进行检测,构建出MMC故障实时诊断系统;最后,综合考虑故障集成单元与故障桥臂位置定位出开路SM,进而完成新型冗余SM条件下MMC的容错运行。利用Matlab/Simulink搭建的19电平MMC模型,验证了所提实时诊断策略的有效性。 展开更多
关键词 1-d CNN 新型冗余SM 开路故障 事件触发 故障实时诊断
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Characteristics of PVT1 and Its Roles in Diseases 被引量:4
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作者 Li Wang Jin-hua He Ze-ping Han 《Chinese Medical Sciences Journal》 CAS CSCD 2014年第4期236-238,共3页
With the development of genome-wide sequencing technology, 195 types of functional, long non-coding RNAs(lnc RNAs) have been identified so far, and their cellular roles are gradually being revealed. Lnc RNAs have now ... With the development of genome-wide sequencing technology, 195 types of functional, long non-coding RNAs(lnc RNAs) have been identified so far, and their cellular roles are gradually being revealed. Lnc RNAs have now become a hotspot in the field of life sciences. These small molecules exist in almost all higher eukaryotes and play very important regulatory roles in these organisms. This review briefly summarizes the recent progress in research on plasmacytoma variant translocation 1 gene(PVT1), an lnc RNA. 展开更多
关键词 long NON-CODING RNAS PLASMACYTOMA VARIANT TRANSLOCATION 1 gene expression characteristics
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Characteristics of Long-term Nonprogressors and Viremia Controllers Infected with HIV-1 via Contaminated Blood Donations or Transfusions Conducted 20 Years Earlier 被引量:3
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作者 LIU Jia FAN Pan Ying +8 位作者 XUE Xiu Juan YAN Jiang Zhou SUN Guo Qing LIU Chun Hua TIAN Sui An LI Ning SUN Ding Yong ZHU Qian WANG Zhe 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第12期907-912,共6页
To characterize long-term nonprogressors (LTNPs) and viremia controllers (VCs), infected with HIV-1 through contaminated blood donation or transfusion between 1992 and 1996 in Henan, China. LTNPs and VCs were defi... To characterize long-term nonprogressors (LTNPs) and viremia controllers (VCs), infected with HIV-1 through contaminated blood donation or transfusion between 1992 and 1996 in Henan, China. LTNPs and VCs were defined by CD4+T lymphocyte (CD4) count and viral load (VL). Of 29,294 patients infected with HIV-1 via contaminated blood donation or transfusion that had conducted for more than 20 years, 92 were LTNPs/VCs. There were 70 LTNPs (0.24%), 43 VCs (0.15%), and 48 LTNPs+VCs- (0.16%). 展开更多
关键词 characteristics of Long-term Nonprogressors HIV-1 v/a Contaminated Blood Donations
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Parameterization, sensitivity, and uncertainty of 1-D thermodynamic thin-ice thickness retrieval
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作者 Tianyu Zhang Mohammed Shokr +5 位作者 Zhida Zhang Fengming Hui Xiao Cheng Zhilun Zhang Jiechen Zhao Chunlei Mi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期93-111,共19页
Retrieval of Thin-Ice Thickness(TIT)using thermodynamic modeling is sensitive to the parameterization of the independent variables(coded in the model)and the uncertainty of the measured input variables.This article ex... Retrieval of Thin-Ice Thickness(TIT)using thermodynamic modeling is sensitive to the parameterization of the independent variables(coded in the model)and the uncertainty of the measured input variables.This article examines the deviation of the classical model’s TIT output when using different parameterization schemes and the sensitivity of the output to the ice thickness.Moreover,it estimates the uncertainty of the output in response to the uncertainties of the input variables.The parameterized independent variables include atmospheric longwave emissivity,air density,specific heat of air,latent heat of ice,conductivity of ice,snow depth,and snow conductivity.Measured input parameters include air temperature,ice surface temperature,and wind speed.Among the independent variables,the results show that the highest deviation is caused by adjusting the parameterization of snow conductivity and depth,followed ice conductivity.The sensitivity of the output TIT to ice thickness is highest when using parameterization of ice conductivity,atmospheric emissivity,and snow conductivity and depth.The retrieved TIT obtained using each parameterization scheme is validated using in situ measurements and satellite-retrieved data.From in situ measurements,the uncertainties of the measured air temperature and surface temperature are found to be high.The resulting uncertainties of TIT are evaluated using perturbations of the input data selected based on the probability distribution of the measurement error.The results show that the overall uncertainty of TIT to air temperature,surface temperature,and wind speed uncertainty is around 0.09 m,0.049 m,and−0.005 m,respectively. 展开更多
关键词 Arctic sea ice 1-d thermodynamic ice model thin-ice thickness sea ice parameterization
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Mineralogical characteristics of polymetallic sulfides from the Deyin-1 hydrothermal field near 15°S, southern Mid-Atlantic Ridge 被引量:4
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作者 WANG Shujie LI Huaiming +3 位作者 ZHAI Shikui YU Zenghui SHAO Zongze CAI Zongwei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期22-34,共13页
A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research & Development A... A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research & Development Association(COMRA). Sulfide samples were collected at three stations from the hydrothermal field during the26 th cruise in 2012. In this paper, mineralogical characteristics of the sulfides were analyzed with optical microscope, X-ray diffractometer, scanning electron microscope and electron microprobe to study the crystallization sequence of minerals and the process of hydrothermal mineralization. According to the difference of the ore-forming metal elements, the sulfide samples can be divided into three types:(1) the Ferich sulfide, which contains mainly pyrite and chalcopyrite;(2) the Fe-Cu-rich sulfide consisting predominantly of pyrite, chalcopyrite and isocubanite, with lesser amount of sphalerite, marmatite and pyrrhotine; and(3) the Fe-Zn-rich sulfide dominated by pyrite, sphalerite and marmatite, with variable amounts of chalcopyrite, isocubanite, pyrrhotine, marcasite, galena and gratonite. Mineral precipitations in these sulfides are in the sequence of chalcopyrite(isocubanite and possible coarse pyrite), fine pyrite,sphalerite(marmatite), galena, gratonite and then the minerals out of the dissolution. Two morphologically distinct generations(Py-I and Py-II) of pyrite are identified in each of the samples; inclusions of marmatite tend to exist in the coarse pyrite crystals(Py-I). Sphalerite in the Fe-Zn-rich sulfide is characterized by a"chalcopyrite disease" phenomenon. Mineral paragenetic relationships and a wide range of chemical compositions suggest that the environment of hydrothermal mineralization was largely changing. By comparison, the Fe-rich sulfide was formed in a relatively stable environment with a high temperature, but the conditions for the formation of the Fe-Cu-rich sulfide were variable. The Fe-Zn-rich sulfide was precipitated during the hydrothermal venting at relatively low temperature. 展开更多
关键词 mineralogical characteristics mineral-forming sequence polymetallic sulfides Deyin-1 hydrothermal field southern Mid-Atlantic Ridge
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Similarities and differences in inherent mechanism and characteristic frequency between the one-dimensional poroelastic model and the layered White model
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作者 Li-Ming Zhao Cai-Ping Lu +1 位作者 Yang Liu Chao-Chao Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2383-2392,共10页
The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D)poroelastic model and the layered White model were investigated.This investigation was conducted under ... The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D)poroelastic model and the layered White model were investigated.This investigation was conducted under the assumption that the rock was homogenous and isotropic at the mesoscopic scale.For the inherent mechanism,both models resulted from quasi-static flow in a slow P-wave diffusion mode,and the differences between them originated from saturated fluids and boundary conditions.On the other hand,for the characteristic frequencies of the models,the characteristic frequency of the 1D poroelastic model was first modified because the elastic constant and formula for calculating it were misused and then compared to that of the layered White model.Both of them moved towards higher frequencies with increasing permeability and decreasing viscosity and diffusion length.The differences between them were due to the diffusion length.The diffusion length for the 1D poroelastic model was determined by the sample length,whereas that for the layered White model was determined by the length of the representative elementary volume(REV).Subsequently,a numerical example was presented to demonstrate the similarities and differences between the models.Finally,published experimental data were interpreted using the 1D poroelastic model combined with the Cole-Cole model.The prediction of the combined model was in good agreement with the experimental data,thereby validating the effectiveness of the 1D poroelastic model.Furthermore,the modified characteristic frequency in our study was much closer to the experimental data than the previous prediction,validating the effectiveness of our modification of the characteristic frequency of the 1D poroelastic model.The investigation provided insight into the internal relationship between wave-induced fluid flow(WIFF)models at macroscopic and mesoscopic scales and can aid in a better understanding of the elastic modulus dispersion and attenuation caused by the WIFF at different scales. 展开更多
关键词 1D poroelastic model Layered White model Quasi-static flow Slow P-wave diffusion characteristic frequency Diffusion length
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Fractal characteristics investigation on electromagnetic scattering from 2-D Weierstrass fractal dielectric rough surface 被引量:1
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作者 任新成 郭立新 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2956-2962,共7页
A normalized two-dimensional band-limited Weierstrass fractal function is used for modelling the dielectric rough surface. An analytic solution of the scattered field is derived based on the Kirchhoff approximation. T... A normalized two-dimensional band-limited Weierstrass fractal function is used for modelling the dielectric rough surface. An analytic solution of the scattered field is derived based on the Kirchhoff approximation. The variance of scattering intensity is presented to study the fractal characteristics through theoretical analysis and numerical calculations. The important conclusion is obtained that the diffracted envelope slopes of scattering pattern can be approximated as a slope of linear equation. This conclusion will be applicable for solving the inverse problem of reconstructing rough surface and remote sensing. 展开更多
关键词 dielectric rough surface 2-d band-limited Weierstrass fractal function fractal characteristics Kirchhoff approximation
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Effects of different dietary energy and protein levels and sex on growth performance,carcass characteristics and meat quality of F1 Angus x Chinese Xiangxi yellow cattle 被引量:24
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作者 Lingyan Li Yuankui Zhu +2 位作者 Xianyou Wang Yang He Binghai Cao 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第4期485-496,共12页
Background:The experiment evaluated the effect of nutrition levels and sex on the growth performance,carcass characteristics and meat quality of F1 Angus × Chinese Xiangxi yellow cattle.Methods:During the backg... Background:The experiment evaluated the effect of nutrition levels and sex on the growth performance,carcass characteristics and meat quality of F1 Angus × Chinese Xiangxi yellow cattle.Methods:During the background period of 184 d,23 steers and 24 heifers were fed the same ration,then put into a2×2×2 factorial arrangement under two levels of- dietary energy(TON:70/80%DM),protein(CP:11.9/14.3%DM)and sex(S:male/female) during the finishing phase of 146 d.The treatments were-(1) high energy/low protein(HELP),(2) high energy/high protein(HEHP),(3) low energy/low protein(LELP) and(4) low energy/high protein(LEHP).Each treatment used 6 steers and 6 heifers,except for HELP- 5 steers and 6 heifers.Results:Growth rate and final carcass weight were unaffected by dietary energy and protein levels or by sex.Compared with the LE diet group,the HE group had significantly lower dry matter intake(DMI,6.76 vs.7.48 kg DM/d),greater chest girth increments(46.1 vs.36.8 cm),higher carcass fat(19.9 vs.16.3%) and intramuscular fat content(29.9 vs.22.8%DM).The HE group also had improved yields of top and medium top grade commercial meat cuts(39.9 vs.36.5%).The dressing percentage was higher for the HP group than the LP group(53.4 vs.54.9%).Steers had a greater length increment(9.0 vs.8.3 cm),but lower carcass fat content(16.8 vs.19.4%) than heifers.The meat quality traits(shear force value,drip loss,cooking loss and water holding capacity) were not affected by treatments or sex,averaging 3.14 kg,2.5,31.5 and 52.9%,respectively.The nutritive profiles(both fatty and amino acid composition) were not influenced by the energy or protein levels or by sex.Conclusions:The dietary energy and protein levels and sex significantly influenced the carcass characteristics and chemical composition of meat but not thegrowth performance,meat quality traits and nutritive profiles. 展开更多
关键词 Carcass characteristics Energy F1 Angus × Chinese Xiangxi yellow cattle Growth performance Meat quality Protein Sex
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Nutritional Composition, Physical Characteristics and Sanitary Quality of the Tomato Variety Mongol F1 from Burkina Faso 被引量:1
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作者 Edwige B. Oboulbiga Charles Parkouda +3 位作者 Hagrétou Sawadogo-Lingani Ella W. R. Compaoré Abdoul Karim Sakira Alfred S. Traoré 《Food and Nutrition Sciences》 2017年第4期444-455,共12页
Tomato (Lycopersicon esculentum Mill) is quantitatively the highest vegetable consumed in Burkina Faso. The objective of this study was to evaluate the physico-chemical, nutritional characteristics, and sanitary quali... Tomato (Lycopersicon esculentum Mill) is quantitatively the highest vegetable consumed in Burkina Faso. The objective of this study was to evaluate the physico-chemical, nutritional characteristics, and sanitary quality of the tomato variety Mongal F1 from different production sites. Twenty-eight (28) samples of Mongal F1 fresh tomatoes were collected from 28 producers at three different localities of Ouahigouya, Loumbila and Ouagadougou. The physico-chemical and nutritional characteristics were determined by standardized methods and the traces metallic elements by atomic absorption spectrophotometry. The results revealed a degree brix varying from 4.07° to 5.50° and a pH ranging from 3.71 to 4.08 corresponding to a total acidity of 0.39% to 0.55% citric acid equivalents. The moisture content, the ash content, the total carbohydrates content, the reducing carbohydrates content, the lipids content and the protein content were ranged from 95.09% to 96.17%, 9.25% to 10.60%, 47.00% to 53.43%, 30.03% to 41.21%, 3.04% to 7.71% and 17.09% to 25.03% respectively. The results of the trace metals showed a high accumulation of total cadmium from 0.11 to 0.22 ppm, of total lead of 1.15 to 1.27 ppm and arsenic total of 0.19 to 0.20 ppm. The results proved that environmental conditions influence the quality of the tomato Mongal F1. Detection of trace elements in the tomato fruits suggests that a better production practices are needed. 展开更多
关键词 TOMATO Mongol F1 characteristics NUTRIENT TRACE METAL
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Characteristics of Chang 2~1 Low PermeabilitySandstone Reservoir in Shunning Oil Field 被引量:1
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作者 WANG Jian-min YU Liu-ying 《Journal of China University of Mining and Technology》 EI 2006年第2期223-227,共5页
Characteristics of Chang 21 low permeability sandstone reservoir of Shunning oil field are analyzed and evaluated based on the data of well logging and experiment. The result shows that 1) the Chang 21 low permeabilit... Characteristics of Chang 21 low permeability sandstone reservoir of Shunning oil field are analyzed and evaluated based on the data of well logging and experiment. The result shows that 1) the Chang 21 low permeability reservoir belongs to the classification of middle-to-fine sized feldspar sandstone, with its components being low in ma- turity, deposited in distributary rivers in the front of the delta; 2) the reservoir is obviously dominated by a low or a very low permeability with a linear variation tendency different from that of the ultra-low permeability reservoir; 3) the spa- tial variation in lithology and physical properties of the reservoir are controlled by the sedimentary facies zones, and 4) the physical property of the reservoir is significantly influenced by clastic constituents and their structure, and the con- stituent of cement materials and their content. The result also shows that the diagenesis action of the reservoir is quite strong in which dissolution greatly modified the reservoir In addition, the inter-granular dissolved pores are the mainly developed ones and the micro-structure is dominated by the combination of middle-to-large sized pores with fine-to-coarse throats. Finally, the radius of the throats is in good exponential correlation with permeability and the seepage capacity comes from those large sized throats. 展开更多
关键词 Chang 2^1 reservoir low permeability: reservoir characteristic EVALUATION
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血浆(1-3)-β-D葡聚糖诊断新生儿侵袭性真菌感染的价值
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作者 邵碧波 刘思佳 李益廷 《中文科技期刊数据库(文摘版)医药卫生》 2024年第3期0001-0004,共4页
探讨在针对新生儿侵袭性真菌感染的诊断中使用血浆(1-3)-β-D葡聚糖能够产生的诊断效能。方法 选取2021年1月到2022年2月因为侵袭性真菌感染于医院寻求医疗干预的新生儿总共60例作为本次研究的一部分研究对象记为1组;另外选取60例健康... 探讨在针对新生儿侵袭性真菌感染的诊断中使用血浆(1-3)-β-D葡聚糖能够产生的诊断效能。方法 选取2021年1月到2022年2月因为侵袭性真菌感染于医院寻求医疗干预的新生儿总共60例作为本次研究的一部分研究对象记为1组;另外选取60例健康婴儿作为2组;统计、对比两组患者的血浆(1-3)-β-D葡聚糖水平、CD4+T淋巴细胞数水平;整理PCR技术针对1组患者诊断结果,将其与血浆(1-3)-β-D葡聚糖诊断侵袭性真菌感染的诊断效能进行对比。结果 研究结果显示1组患者的血浆(1-3)-β-D葡聚糖水平、CD4+T淋巴细胞数水平较之于2组患者存在明显差异,1组患者血浆(1-3)-β-D葡聚糖水平更高,而CD4+T淋巴细胞数水平明显更低;P<0.05。在针对诊断效能的考察上,血浆(1-3)-β-D葡聚糖诊断效能和PCR诊断结果之间在灵敏度、特异度方面差异不大,P>0.05。结论 针对罹患侵袭性真菌感染的新生儿使用血浆(1-3)-β-D葡聚糖进行检查,一定程度上能够确保诊断结果的严谨程度,可使用。 展开更多
关键词 侵袭性真菌感染 诊断 血浆(1-3)-β-d葡聚糖
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血浆(1,3)-β-D葡聚糖检测在侵袭性真菌感染诊断中的价值分析
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作者 王珍珍 《中国科技期刊数据库 医药》 2024年第9期0150-0153,共4页
研究血浆(1,3)-β-D葡聚糖检测技术(G实验)应用于侵袭性真菌感染(IFI)诊断中的应用价值。方法 选择我院在2023年1月至2024年1月期间收治的100例高危型侵袭型真菌感染患者,应用MB-80微生物快速检测动态系统以及对应的试剂对患者的血浆(1,... 研究血浆(1,3)-β-D葡聚糖检测技术(G实验)应用于侵袭性真菌感染(IFI)诊断中的应用价值。方法 选择我院在2023年1月至2024年1月期间收治的100例高危型侵袭型真菌感染患者,应用MB-80微生物快速检测动态系统以及对应的试剂对患者的血浆(1,3)-β-D葡聚糖进行检测,分析真菌培养、G实验和联合检测结果;三种方法的诊断效能;三种方法的ROC曲线。结果 确诊IFI阳性共28例,阴性共72例;联合检测的诊断效能高于真菌培养或者G实验。联合检测面积高于单一检测。结论 在侵袭性真菌感染的诊断中,应用血浆(1,3)-β-D葡聚糖检测,诊断效能良好,在和传统真菌培养技术联合检测下,可进一步提升诊断效能。 展开更多
关键词 血浆(1 3)-β-d葡聚糖检测技术 侵袭性真菌感染 诊断效能
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Study on diversity and temporal-spatial characteristics of eukaryotic microorganisms on Glacier No.1 at the Urumqi River Head,Tianshan
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作者 Wei Zhang GaoSen Zhang +2 位作者 GuangXiu Liu ZhongQin Li LiZhe An 《Research in Cold and Arid Regions》 2011年第4期306-313,共8页
Surface snow samples of different altitudes and snow pit samples were collected from Glacier No. 1 at the Urumqi River Head, Tianshan. Denaturing gradient gel electrophoresis (DGGE) was used to examine the diversity... Surface snow samples of different altitudes and snow pit samples were collected from Glacier No. 1 at the Urumqi River Head, Tianshan. Denaturing gradient gel electrophoresis (DGGE) was used to examine the diversity and temporal-spatial characteristics of eukaryotic microorganisms with different altitudes and depths. Results show that the eukaryotic microorganisms belong to four kingdoms--Viridiplantae, Fungi, Amoebozoa, and Alveolata. Among them, algae (especially Chlamydomonadales) were the dominant group. The diversity of eukaryotic microorganisms was negatively correlated with altitude and accumulation time, but positively correlated with 8180 values. These results indicate that temperature is the main factor for the temporal-spatial change of eukaryotic microorganisms, and the diversity of eukaryotic microorganisms could be an index for climate and environmental change. 展开更多
关键词 Glacier No.1 at the Urumqi River Head eukaryotic microorganisms DIVERSITY temporal-spatial characteristics DGGE
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Experimental Studies on Impulse Flashover Characteristics of Tower Head Air Gaps of±1 000 kV DC Transmission Lines and 被引量:1
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作者 DING Yujian LIAO Weiming SUN Zhaoying SU Zhiyi 《中国电机工程学报》 EI CSCD 北大核心 2011年第34期I0010-I0010,共1页
关键词 英文摘要 内容介绍 编辑工作 期刊
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Molecular Characteristics of S1 Gene of Infectious Bronchitis Virus Isolated from Chicken Proventriculus
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作者 CHENG Li-qin, ZHOU Ji-yong, John Dikki, SHEN Xing-yan, CHEN Ji-gang and ZHANG De-yongInstitute of Preventive Veterinary Medicine , College of Animal Sciences , Zhejiang University , Hangzhou 310029 , P.R.China 《Agricultural Sciences in China》 CAS CSCD 2003年第1期107-112,共6页
Infectious bronchitis virus was isolated from swollen proventriculi of clinically ill chicken. The suspected virus samples (2/97, 3/97, 1/98) were adapted in SPF chicken embryos for virus isolation and identification.... Infectious bronchitis virus was isolated from swollen proventriculi of clinically ill chicken. The suspected virus samples (2/97, 3/97, 1/98) were adapted in SPF chicken embryos for virus isolation and identification. All the virus isolates were able to agglutinate chicken erythrocytes after treatment with trypsin, and interfer with the reproduction of Newcastle disease virus in chicken embryos, and have low antigenic relat-edness values with reference positive IBV. The isolates 2/97, 3/97, 1/98 RNAs extracted from the allantoic fluid of inoculated embryonated eggs were converted to cDNA by reverse transcription with 3'-primer of S1 gene of (IBV). Polymerase chain reaction (PCR) was performed with two primers which span the S1 gene. Amplified product of 1. 93 kb was subjected to EcoR I and BamH I digestion and the fragments obtained were the same as expected size. The PCR product was ligated to pBlueScript-SK ( + ) vector, and its nucleotide sequence was determined by the dideoxy-mediated chain termination method. Nucleotide sequence analysis showed 73. 6 - 99. 7% homology between the isolated IBV and the IBV strains in GenBank. The homology of amino acid was 71. 4 - 99.4%. 展开更多
关键词 CHICKEN Infectious bronchitis virus S1 gene Molecular characteristics
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