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Effects of Health Education with Problem-Based Learning Approaches on the Knowledge, Attitude, Practice and Coping Skills of Women with High-Risk Pregnancies in Plateau Areas
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作者 Ying Wu Suolang Sezhen +5 位作者 Renqing Yuzhen Hong Wei Zhijuan Zhan Baima Hongying Yuhong Zhang Lihong Liu 《Open Journal of Nursing》 2024年第5期192-199,共8页
Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approach... Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approaches on the knowledge, attitude, practice, and coping skills of women with high-risk pregnancies in this region. Methods: 76 high-risk pregnancy cases were enrolled at Tibet’s Linzhi People’s Hospital between September 2023 and April 2024. 30 patients admitted between September 2023 and December 2023 were selected as the control group and were performed with regular patient education. 46 patients admitted between January 2024 and April 2024 were selected as the observation group and were performed regular patient education with problem-based learning approaches. Two groups’ performance on their health knowledge, attitude, practice and coping skills before and after interventions were evaluated, and patient satisfaction were measured at the end of the study. Results: There was no statistical significance (P P P Conclusions: Health education with problem-based learning approaches is worth promoting as it can help high-risk pregnant women in plateau areas develop better health knowledge, attitude and practice and healthier coping skills. Also, it can improve patient sanctification. 展开更多
关键词 plateau Areas Patients with high-Risk Pregnancies Problem-Based Learning Health Education Health Knowledge Attitude and Practice Coping Skills
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Mitochondrial genome sequences of Artemia tibetiana and Artemia urmiana:assessing molecular changes for high plateau adaptation 被引量:4
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作者 ZHANG HangXiao LUO QiBin +4 位作者 SUN Jing LIU Fei WU Gang YU Jun WANG WeiWei 《Science China(Life Sciences)》 SCIE CAS 2013年第5期440-452,共13页
Brine shrimps,Artemia(Crustacea,Anostraca),inhabit hypersaline environments and have a broad geographical distribution from sea level to high plateaus.Artemia therefore possess significant genetic diversity,which give... Brine shrimps,Artemia(Crustacea,Anostraca),inhabit hypersaline environments and have a broad geographical distribution from sea level to high plateaus.Artemia therefore possess significant genetic diversity,which gives them their outstanding adaptability.To understand this remarkable plasticity,we sequenced the mitochondrial genomes of two Artemia tibetiana isolates from the Tibetan Plateau in China and one Artemia urmiana isolate from Lake Urmia in Iran and compared them with the genome of a low-altitude Artemia,A.franciscana.We compared the ratio of the rate of nonsynonymous(Ka) and synonymous(Ks) substitutions(Ka/Ks ratio) in the mitochondrial protein-coding gene sequences and found that atp8 had the highest Ka/Ks ratios in comparisons of A.franciscana with either A.tibetiana or A.urmiana and that atp6 had the highest Ka/Ks ratio between A.tibetiana and A.urmiana.Atp6 may have experienced strong selective pressure for high-altitude adaptation because although A.tibetiana and A.urmiana are closely related they live at different altitudes.We identified two extended termination-associated sequences and three conserved sequence blocks in the D-loop region of the mitochondrial genomes.We propose that sequence variations in the D-loop region and in the subunits of the respiratory chain complexes independently or collectively contribute to the adaptation of Artemia to different altitudes. 展开更多
关键词 基因组序列 线粒体蛋白 青藏高原 卤虫 D-LOOP区 丰年虫 分子 评估
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CMIP6 HighResMIP对青藏高原气候模拟的评估和预估 被引量:1
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作者 杨珂珂 郭东林 +2 位作者 华维 马迪 辛羽婷 《大气科学学报》 CSCD 北大核心 2023年第2期193-204,共12页
高分辨率模式模拟被认为是研究资料相对欠缺的青藏高原地区气候变化的重要方法之一。第六次国际耦合模式比较计划(CMIP6)新增了高分辨率模式比较计划(HighResMIP),但其对青藏高原气候的模拟性能尚未系统评估。本研究分析了6对(更高、较... 高分辨率模式模拟被认为是研究资料相对欠缺的青藏高原地区气候变化的重要方法之一。第六次国际耦合模式比较计划(CMIP6)新增了高分辨率模式比较计划(HighResMIP),但其对青藏高原气候的模拟性能尚未系统评估。本研究分析了6对(更高、较低分辨率)CMIP6 HighResMIP模式对青藏高原当前气候的模拟能力,并集合预估了近期青藏高原气候的变化趋势。相对较粗分辨率模拟,所有(2/3)模式的更高分辨率模拟减少了平均降水(气温)的区域平均偏差。泰勒图涉及指标的综合评估显示,约1/3模式的更高分辨率对平均气温和降水模拟效果优于较低分辨率,其余模式的更高分辨率则接近或者劣于较低分辨率。集合平均结果优于单个模式,且其更高分辨率模拟效果总体优于较低分辨率。更高分辨率模式集合预估显示,相对于1995—2014年,在SSP5-8.5情景下到2021—2040年青藏高原整体呈增温趋势,东南部增温相对较弱;降水从北到南呈增加-减少-增加的变化模态;青藏高原气温将平均增加(0.81±0.91)℃,降水将平均增加(0.05±0.25) mm/d。 展开更多
关键词 青藏高原 气候变化 highResM IP 高分辨率模拟
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THE HIGH RESOLUTION SEISMIC TOMOGRAPHIC IMAGE IN QINGHAI—TIBET PLATEAU AND ITS DYNAMIC IMPLICATIONS 被引量:2
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作者 Zhu Jieshou,Cai Xuelin,Cao Jiamin,Yan Zhongqun,Cao Xiaolin,Liang Chuntao 《地学前缘》 EI CAS CSCD 2000年第S1期354-356,共3页
The Qinghai—Tibet plateau and its surrounding areas including Indian subcontinent, Xinjiang, Mongolia, is a largest lithosphere convergence place in the world, which characterized by continent\|continent collision wi... The Qinghai—Tibet plateau and its surrounding areas including Indian subcontinent, Xinjiang, Mongolia, is a largest lithosphere convergence place in the world, which characterized by continent\|continent collision with a thick crust and lithosphere. The high resolution seismic surface wave tomographic inversion has been conducted for studying the 3D velocity structure of crust and upper mantle in those areas. The seismic surface waveform data are from the archives of the CDSN, GSN and GEOSCOPE. About 2400 long period surface waveform recordings are available for both dispersion and waveform tomographic inversion. The block inversion by grid 1°×1°in Qinghai—Tibet plateau and 2°×2°in the surrounding areas were adapted. The resulting maps show the high resolution 3D shear wave velocity variation from earth’s surface to 400km depth. 展开更多
关键词 SEISMIC tomographic IMAGE high resolution DYNAMIC Qinghai—Tibet plateau
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Regular Observation of De-Acclimatization and Randomized Controlled Research of Diagnostic Criteria of High Altitude De-Acclimatization Syndrome among Different Plateau Migrants Crowd after Their Return to the Plain 被引量:2
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作者 Qiquan Zhou Shengyue Yang +9 位作者 Zhencai Yuan Yinhu Wang Xuefeng Zhang Wei Gao Zifu Shi Youli Yang Yunhong Wu Yong Fan Fuling Wang Guansong Wang 《Occupational Diseases and Environmental Medicine》 2014年第4期86-100,共15页
Objective: The objective of this study was to investigate the diagnostic methods of high altitude de-acclimatization syndrome and to formulate diagnostic criteria. Methods: This study was conducted using epidemiologic... Objective: The objective of this study was to investigate the diagnostic methods of high altitude de-acclimatization syndrome and to formulate diagnostic criteria. Methods: This study was conducted using epidemiological surveys and a multi-center randomized controlled clinical trial. A total of 3011 subjects were studied, and the following indices were collected after their return to low altitude areas from the plateau: general health status, blood, urine and stool samples, myo-cardial enzyme levels, liver and kidney function, nerve function, sex hormone levels, microalbuminuria, electrocardiogram (ECG), echocardiography, pulmonary function, and hemorheological markers. These data were compared to those of randomized healthy subjects in the same age range who lived at the same altitude to determine the characteristics of high altitude de-acclimatization syndrome. Based on these characteristics, diagnostic criteria for high altitude de-acclimatization syndrome were formulated. Results: This study demonstrated that the incidence of high altitude de-acclimatization syndrome was 84.36%. Sixty percent of the cases were mild, 30% were medium, and 10% were severe. The incidence was higher among those who returned to a place of lower altitude, resided at a high altitude for a longer period of time, or engaged in heavy labor while at high altitude. Patients with high altitude de-acclimatization syndrome manifested hematological abnormalities and abnormal ventricular function, notably a right ventricular diastolic function, which recovered to baseline function after one to five years. Exposure to long-term hypoxia often caused obvious changes in cardiac morphology, i.e., left and right ventricular hypertrophy, particularly within the right ventricle. In addition, patients with high altitude de-acclimatization syndrome often presented with low blood pressure, low pulse pressure, and microalbuminuria. A few patients presented with occult blood in their feces. The diagnosis of high altitude de-acclimatization syndrome can be made if a patient who recently returns to the plain from the plateau complains of dizziness, weakness, sleepiness, chest tightness, edema, memory loss, and other symptoms and signs that do not alleviate under short-term rehabilitation or symptomatic treatment, and if organic diseases of the heart, lung, kidney, and other organs have been excluded. Conclusion: The diagnosis of high altitude de-acclimatization syndrome should be made after a comprehensive analysis of the patient’s clinical symptoms and signs. 展开更多
关键词 plateau MIGRANTS Low ALTITUDE high ALTITUDE De-Acclimatization SYNDROME Diagnostic Criteria Multi-Center Study
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Determination and Temperature Dependence of Plateau Modulus for Polymerization of Propylene to Isotactic Polypropylene with Ultra-high Molecular Weight under Catalysis of Ziegler-Natta Catalyst 被引量:1
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作者 DINGJian DINGXue-jia XURi-wei YUDing-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第2期227-231,共5页
The viscoelastic behavior of isotactic polypropylene with ultra-high molecular weight(UHPPH) and broad molecular weight distribution(MWD), produced in the presence of Ziegler-Natta catalyst, was investigated by means ... The viscoelastic behavior of isotactic polypropylene with ultra-high molecular weight(UHPPH) and broad molecular weight distribution(MWD), produced in the presence of Ziegler-Natta catalyst, was investigated by means of oscillatory rheometry at 180 and 200 ℃, whose loss modulus(G″) plots at 180 and 200 ℃ versus the natural logarithm of angular frequency(ω) present a pronounced maximum at 34.35 and 69.21 rad/s, respectively, and do not show a maximum peak at 0.01-100 rad/s for Ziegler-Natta catalyzing ethylene-propylene random copolymerization(PPR) with a conventional molecular weight and broad MWD. The fact indicates that the high molecular weight is responsible for a maximum peak of G″(ω) vs. lnω curves for UHPPH. This makes it possible to determine the plateau modulus(G 0_N) of UHPPH from a certain experimental temperature G″(ω) curve directly. For UHPPH, the G 0_N determined to be 4.28×10 5 and 3.62×10 5 Pa at 180 and 200 ℃, respectively, decreases with the increase of temperature and is independent of the molecular weight, which directly confirms reputation theoretical prediction that the G 0_N has no relation to the molecular weight. 展开更多
关键词 Isotactic polypropylene Ultra-high molecular weight Broad molecular weight distribution plateau modulus
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Impact of Surface Sensible Heating over the Tibetan Plateau on the Western Pacific Subtropical High: A Land–Air–Sea Interaction Perspective 被引量:17
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作者 Anmin DUAN Ruizao SUN Jinhai HE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第2期157-168,共12页
The impact of surface sensible heating over the Tibetan Plateau (SHTP) on the western Pacific subtropical high (WPSH) with and without air-sea interaction was investigated in this study. Data analysis indicated th... The impact of surface sensible heating over the Tibetan Plateau (SHTP) on the western Pacific subtropical high (WPSH) with and without air-sea interaction was investigated in this study. Data analysis indicated that SHTP acts as a relatively independent factor in modulating the WPSH anomaly compared with ENSO events. Stronger spring SHTP is usually fol- lowed by an enhanced and westward extension of the WPSH in summer, and vice versa. Numerical experiments using both an AGCM and a CGCM confirmed that SHTP influences the large-scale circulation anomaly over the Pacific, which features a barotropic anticyclonic response over the northwestern Pacific and a cyclonic response to the south. Owing to different background circulation in spring and summer, such a response facilitates a subdued WPSH in spring but an en- hanced WPSH in summer. Moreover, the CGCM results showed that the equatorial low-level westerly at the south edge of the cyclonic anomaly brings about a warm SST anomaly (SSTA) in the equatorial central Pacific via surface warm advection. Subsequently, an atmospheric Rossby wave is stimulated to the northwest of the warm SSTA, which in turn enhances the at- mospheric dipole anomalies over the western Pacific. Therefore, the air-sea feedbacks involved tend to reinforce the effect of SHTP on the WPSH anomaly, and the role of SHTP on general circulation needs to be considered in a land-air-sea interaction framework. 展开更多
关键词 Tibetan plateau surface sensible heating western Pacific subtropical high ENSO tropical air-sea interaction
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NUMERICAL EXPERIMENT OF MEDIUM-RANGE CHANGE OF THE SUBTROPICAL HIGH Ⅰ.THE INFLUENCE OF THE HEATINGSOURCE OVER TIBET PLATEAU
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作者 巩远发 纪立人 《Journal of Tropical Meteorology》 SCIE 1998年第2期148-154,共7页
The medium-range change of the subtropical high of June 1979 and its influences of the heating sources over Tibet Plateau are studied by using a global circulation spectrum-model. The analyses of the simulation result... The medium-range change of the subtropical high of June 1979 and its influences of the heating sources over Tibet Plateau are studied by using a global circulation spectrum-model. The analyses of the simulation results show that the heating sources over Tibet Plateau play an important role in the process of frontogenesis. the intensity of frontal zone and the upper-tropospheric westerly jet associated with it. When there are heating sources over Tibet Plateau. both the frontal zone and westerly jet are stronger. There are very important mutual relations between the sensible heating and latent heating. After the sensible heating and latent heating are isolated.it departs much from reality that the significance of them are 展开更多
关键词 numerical experiment SUBTROPICAL high sensible HEATING LATENT HEATING TIBET plateau
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Diagnostic criteria of high altitude de-acclimatization syndrome among plateau migrants after their return to the plain: a multi-center randomized controlled trial
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作者 Qi-quan Zhou Sheng-yue Yang +9 位作者 Zhen-cai Yuan Yin-hu Wang Xue-feng Zhang Wei Gao Zi-fu Shi You-li Yang Yun-hong Wu Yong Fan Fu-ling Wang Guan-song Wang 《Journal of Medical Colleges of PLA(China)》 CAS 2015年第1期35-45,共11页
Objective: The objective of this study was to investigate the diagnostic methods of high altitude de-acclimatization syndrome and to formulate diagnostic criteria.Methods: This study was conducted using epidemiologica... Objective: The objective of this study was to investigate the diagnostic methods of high altitude de-acclimatization syndrome and to formulate diagnostic criteria.Methods: This study was conducted using epidemiological surveys and a multi-center randomized controlled clinical trial. A total of 3,011 subjects were studied, and the following indices were collected after their return to low altitude areas from the plateau: general health status, blood, urine and stool samples, myocardial enzyme levels, liver and kidney function, nerve function, sex hormone levels, microalbuminuria, electrocardiogram(ECG), echocardiography, pulmonary function, and hemorheological markers. These data were compared to those of randomized healthy subjects in the same age range who lived at the same altitude to determine the characteristics of high altitude deacclimatization syndrome. Based on these characteristics, diagnostic criteria for high altitude de-acclimatization syndrome were formulated.Results: This study demonstrated that the incidence of high altitude de-acclimatization syndrome was 84.36%. Sixty percent of the cases were mild, 30% were medium, and 10% were severe. The incidence was higher among those who returned to a place of lower altitude, resided at a high altitude for a longer period of time, or engaged in heavy labor while at high altitude. Patients with high altitude de-acclimatization syndrome manifested hematological abnormalities and abnormal ventricular function, notably a right ventricular diastolic function, which recovered to baseline function after one to five years. Exposure to long-term hypoxia often caused obvious changes in cardiac morphology, i.e., left and right ventricular hypertrophy, particularly within the right ventricle. In addition, patients with high altitude de-acclimatization syndrome often presented with low blood pressure, low pulse pressure, and microalbuminuria. A few patients presented with occult blood in their feces. The diagnosis of high altitude deacclimatization syndrome can be made if a patient who recently returns to the plain from the plateau complains of dizziness, weakness, sleepiness, chest tightness, edema, memory loss, and other symptoms and signs that do not alleviate under short-term rehabilitation or symptomatic treatment, and if organic diseases of the heart, lung, kidney, and other organs have been excluded.Conclusion: The diagnosis of high altitude de-acclimatization syndrome should be made after a comprehensive analysis of the patient's clinical symptoms and signs. 展开更多
关键词 plateau MIGRANTS Low ALTITUDE high ALTITUDE de-acclimatization SYNDROME Diagnostic criteria Multicenter study
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Petrogenesis of high-Mg# Cenozoic volcanic rocks of southern Qiangtang area, Tibetan Plateau: geochemical and Sr-Nd isotopic evidence
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作者 FAN Lefu CHI Xiaoguo +3 位作者 LIU Jianfeng ZHANG Rui WANG Limin SUN Wei 《Global Geology》 2015年第3期174-182,共9页
The Nadingcuo volcanic rock suite is the most voluminous Cenozoic volcanic suite in the southern Qiangtang area of the northern Tibetan Plateau. These high-K calc-alkaline volcanic rocks were formed between36 and 34 M... The Nadingcuo volcanic rock suite is the most voluminous Cenozoic volcanic suite in the southern Qiangtang area of the northern Tibetan Plateau. These high-K calc-alkaline volcanic rocks were formed between36 and 34 Ma,characterized by high Mg#values,high concentrations of Ti O2 and P2O5,87 Sr /86 Sr ratios of0. 704682--0. 706 112,and εNd( t) values of- 1. 2 to 1. 6. There is a lack of reasonable explanations for sourcing and origin of magmas that formed the rocks with high Mg#values and Ti O2 and P2O5enrichments,which makes the previous research results still controversial. This study reviews the geochemical characteristics of Nadingcuo volcanic rocks and the data we have newly found in our fieldwork. We give some new interpretation to the magmatic evolution of the basaltic magmas in the discussed area dominated by fractional crystallization.The geochemistry of trachyandesite and trachyte units in the studied area is indicative of formation from mantlederived magmas that mixed with crustal materials. The high values of Mg#and Ti O2 and P2O5enrichment in these units are evident to show the mixing between mantle-derived magmas with ~ 30--40 wt.% rhyolitic melt or assimilation of a similar amount of felsic rocks. The geochemistry of basaltic rocks in the area also suggests that the Nadingcuo basalts may have been derived from an ocean island basalt( OIB)-type source that contained and was mixed with ancient mantle wedge derived material,indicating that a 36--34 Ma asthenospheric upwelling event in the Qiangtang area may relate to the northward subduction of Indian lithospheric mantle and the southward subduction of Asian lithospheric mantle. This upwelling of asthenospheric material was centered in the southern Qiangtang area between 36 and 34 Ma,while the northward movement of the Indian Craton caused this upwelling mantle flow to continuously migrate northward,resulting in the current centering of this upwelling in the Hoh Xil-Kunlun region. 展开更多
关键词 新生代火山岩 地球化学特征 羌塘地区 SR-ND同位素 高镁 青藏高原 洋岛玄武岩 长英质岩石
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基于QAR数据的民机高高原进近着陆风险评估方法
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作者 陈农田 满永政 李俊辉 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第1期77-85,共9页
民机高高原进近着陆是高原飞行高风险阶段。为有效实施高高原进近着陆风险识别和等级判据,提出基于熵权可变模糊识别的长短时记忆网络与深度神经网络(LSTM-DNN)相融合的深度学习风险评估方法。基于快速存取记录器(QAR)记录的高高原飞行... 民机高高原进近着陆是高原飞行高风险阶段。为有效实施高高原进近着陆风险识别和等级判据,提出基于熵权可变模糊识别的长短时记忆网络与深度神经网络(LSTM-DNN)相融合的深度学习风险评估方法。基于快速存取记录器(QAR)记录的高高原飞行数据,借鉴民机飞行品质监控(FOQA)咨询通告和行业QAR监控标准,结合指标重要度分析与Delphi专家调查,提取着陆时航向变化大、航迹低、610~305 m进近时下降率大、接地时垂直加速度及153~15 m进近时下降率大5个关键监控项目作为民机高高原进近着陆风险评估指标。为克服评估指标权重主观性偏差,应用熵权法确定评估指标权重,基于可变模糊识别方法构建风险等级隶属函数,建立基于LSTM-DNN的民机高高原进近着陆风险评估模型。以成都—拉萨进近着陆航段为例,提取QAR数据,对该风险评估模型进行训练与测试,并与Logistic多元回归、支持向量机(SVM)等评估方法进行比较,结果表明:所提方法平均准确率达到94.18%,最高可达94.79%,验证了方法的客观有效性。 展开更多
关键词 高高原飞行 快速存取记录器数据 熵权 可变模糊识别 LSTM-DNN深度学习 风险评估
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黄河流域-黄土高原水土保持与高质量发展:成效、问题与对策 被引量:1
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作者 邓蕾 王凯博 +2 位作者 汪晓珍 李继伟 上官周平 《河南师范大学学报(自然科学版)》 CAS 北大核心 2024年第1期1-7,F0002,共8页
水土保持是新时期山水林田湖草沙系统治理的核心,在保障黄土高原生态安全屏障方面具有重要作用.黄土高原地区自实施一系列生态治理工程以来,水土保持和生态建设等成绩斐然.基于长期监测及生态系统关键过程等研究基础,分析了黄土高原水... 水土保持是新时期山水林田湖草沙系统治理的核心,在保障黄土高原生态安全屏障方面具有重要作用.黄土高原地区自实施一系列生态治理工程以来,水土保持和生态建设等成绩斐然.基于长期监测及生态系统关键过程等研究基础,分析了黄土高原水土保持与生态治理的成效,剖析了水土保持高质量发展中存在的主要问题,主要表现在区域脆弱的生态环境仍未根本改变、生态系统稳定性仍面临巨大挑战、灾害风险依然较为严重、水土保持监管水平薄弱等方面.据此,从该地区水土保持与生态高质量发展角度出发,提出了未来黄土高原水土保持与高质量发展的若干对策建议,以更好地服务黄河流域生态保护和高质量发展的国家战略. 展开更多
关键词 黄土高原 水土保持 生态治理 高质量发展
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高高原受限空间内小尺度油池火燃烧特性试验研究 被引量:1
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作者 代尚沛 贾旭宏 +1 位作者 丁思婕 朱新华 《消防科学与技术》 CAS 北大核心 2024年第2期161-167,共7页
为研究我国高高原地区的受限空间内液体燃料小尺度油池火燃烧特性,在高高原康定机场自主搭建受限空间内油池火的试验平台。共选取3类典型液体燃料(航空煤油、航空汽油、正庚烷)进行燃烧试验,测量火焰高度、火焰温度和烟气成分等变化规律... 为研究我国高高原地区的受限空间内液体燃料小尺度油池火燃烧特性,在高高原康定机场自主搭建受限空间内油池火的试验平台。共选取3类典型液体燃料(航空煤油、航空汽油、正庚烷)进行燃烧试验,测量火焰高度、火焰温度和烟气成分等变化规律,研究了高高原受限空间内小尺度油池火行为。研究发现:在高高原地区,正庚烷稳定燃烧阶段的平均火焰高度可以通过模型L/D=k+0.254Q^(2/5)/D表示,其中,火焰高度与压力之间的关系式为L/D~p^(-2/9)。3种燃料的火焰最高温度均超过600℃,而羽流轴线温升与火焰高度呈现-5/3的指数关系。产烟速率则表现出对环境压力的依赖性,其关系可表示为:v~p^(-1/3)。 展开更多
关键词 高高原受限空间 油池火 火焰高度 火焰温度 烟气成分
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模拟高高原机场疏散的低氧实验平台设计
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作者 陶振翔 胡培峰 +3 位作者 刘潇瀚 李滢 黄凯鑫 杨锐 《实验技术与管理》 CAS 北大核心 2024年第3期29-35,共7页
为克服高高原机场疏散研究中实地实验的挑战,设计并研制了一套可以模拟高高原环境的低氧实验平台。综合利用文献调研、实验室测试等方法,分别从生理层面与认知层面设计了三组对照实验方案,即上下台阶实验、90 s跑步实验和反应能力实验,... 为克服高高原机场疏散研究中实地实验的挑战,设计并研制了一套可以模拟高高原环境的低氧实验平台。综合利用文献调研、实验室测试等方法,分别从生理层面与认知层面设计了三组对照实验方案,即上下台阶实验、90 s跑步实验和反应能力实验,以模拟真实疏散情景。基于统计学原理,对比分析了高高原实地实验与低氧实验平台实验得到的心率、血氧、反应能力等数据。研究结果表明,三组对照试验数据无显著差异性,验证了该平台模拟高高原环境的可行性和合理性。该实验平台可为安全人机、职业卫生等领域的实验研究与教学创新提供支持。 展开更多
关键词 高高原机场 生理反应 认知反应 低氧环境
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夏季南亚高压东-西振荡过程中青藏高原及周边上对流层水汽的分布和传输特征
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作者 唐南军 任荣彩 +1 位作者 祝传栋 吴国雄 《大气科学》 CSCD 北大核心 2024年第3期967-986,共20页
夏季南亚高压的“双模态”分布对应着其中心位置在10~20天准双周时间尺度上的东—西振荡,对青藏高原及周边上对流层的水汽分布和传输有显著影响。本文利用夏季7~8月逐日的ERAI再分析资料,通过基于南亚高压东—西振荡指数的位相合成分析... 夏季南亚高压的“双模态”分布对应着其中心位置在10~20天准双周时间尺度上的东—西振荡,对青藏高原及周边上对流层的水汽分布和传输有显著影响。本文利用夏季7~8月逐日的ERAI再分析资料,通过基于南亚高压东—西振荡指数的位相合成分析发现,当南亚高压呈青藏高原模态时,青藏高原(伊朗高原)地区上对流层水汽含量异常偏高(低),伊朗高原模态时则相反;伴随南亚高压中心位置由青藏高原向西移至伊朗高原上空,上对流层水汽含量正异常中心亦自青藏高原东侧向西逐渐传播到伊朗高原以西地区。进一步诊断表明,除了在青藏高原北侧和南侧水汽经向绝热输送异常有抵消作用外,两高原地区上对流层水汽倾向异常主要由水汽纬向绝热输送异常及其辐合辐散异常所贡献,而青藏高原地区对流活动引起的垂直非绝热输送异常在上对流层则主要与剩余项(水汽的凝结和蒸发)相抵消。因此,青藏高原(伊朗高原)上对流层为水汽含量正异常时对应着青藏高原上空的对流活动异常偏弱(强)。而南亚高压中心位置和上对流层水汽含量正异常中心自青藏高原向伊朗高原移动的过程,对应着青藏高原地区的对流活动异常和垂直向上的水汽非绝热输送异常不断增强,同时上对流层水汽凝结异常也不断增强。此外,南亚高压向西移动过程中,上对流层水汽绝热辐合(辐散)异常主要发生在其西(东)侧,这是造成水汽含量异常中心纬向传播的主要原因。 展开更多
关键词 南亚高压东—西振荡 青藏高原周边 上对流层水汽 分布与传输
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基于航空运行需求的高高原机场温度特征分析——以林芝机场为例
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作者 庞毅 吴俊杰 《科技和产业》 2024年第3期269-272,共4页
高高原机场在地方经济发展中发挥着至关重要的作用,但温度异常会对运行效率和安全产生直接影响。对林芝机场2006—2020年温度数据进行统计分析,结果表明:机场全年1—8月升温慢,9—12月降温快;机场夏季日较差最小,在10℃左右,冬季最大,... 高高原机场在地方经济发展中发挥着至关重要的作用,但温度异常会对运行效率和安全产生直接影响。对林芝机场2006—2020年温度数据进行统计分析,结果表明:机场全年1—8月升温慢,9—12月降温快;机场夏季日较差最小,在10℃左右,冬季最大,在15℃左右;机场低温日(日最低温度<0℃)集中在12月和1月,高温日(日最高温度>20℃)集中在6—9月;机场平均温度呈现缓慢上升趋势,约为0.22℃/15 a,夏季升温趋势为0.28℃/15 a,冬季升温更达到了0.51℃/15 a。 展开更多
关键词 高高原机场 林芝机场 温度 特征分析
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藏北环纳木错湖区岩画遗存的时代分析
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作者 庞颖 汤惠生 李永宪 《西藏大学学报(社会科学版)》 北大核心 2024年第2期26-41,共16页
文章是2021年“环纳木错湖泊区科学考察队”对西藏纳木错及藏北高海拔湖区岩画考古调查的年代学研究报告。文章对纳木错扎西岛、尼玛县加林山和夏桑三处具有代表性的岩画遗存进行了包括U-Th与C14测年技术在内的考古学综合分析,认为纳木... 文章是2021年“环纳木错湖泊区科学考察队”对西藏纳木错及藏北高海拔湖区岩画考古调查的年代学研究报告。文章对纳木错扎西岛、尼玛县加林山和夏桑三处具有代表性的岩画遗存进行了包括U-Th与C14测年技术在内的考古学综合分析,认为纳木错等藏北内陆湖泊地区两种技术(琢刻、涂绘)制作的岩画其时代是基本平行共存的,该区域大量岩画制作于距今2000年前后至7~9世纪的吐蕃时期,U-Th与C14测年数据还显示其中涂绘岩画的制作可能早到距今2200年或更早。对岩画遗存形式的分析表明,纳木错扎西岛至少在公元7~9世纪,已是藏北神祇崇拜及宗教信仰的重要场所,而不同文化因素的岩画显示出古代西藏积极参与“高原丝绸之路”的文化互动,即古代西藏与不同民族和地区文化的交往交流与交融。 展开更多
关键词 藏北大湖区岩画 U-Th与C14测年技术 图像文化因素 “高原丝绸之路”
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以新质生产力促进西藏低空经济高质量发展的策略研究
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作者 肖星月 谢春生 +2 位作者 孙惠君 黄保全 杨洋 《西藏发展论坛》 2024年第3期57-61,共5页
新质生产力是创新起主导作用,摆脱传统经济增长方式、生产力发展路径,具有高科技、高效能、高质量特征,符合新发展理念的先进生产力质态。本文从新质生产力核心内涵及其对高质量发展的现实意义为出发点,结合低空经济作为新兴产业所呈现... 新质生产力是创新起主导作用,摆脱传统经济增长方式、生产力发展路径,具有高科技、高效能、高质量特征,符合新发展理念的先进生产力质态。本文从新质生产力核心内涵及其对高质量发展的现实意义为出发点,结合低空经济作为新兴产业所呈现的典型特征,分析新质生产力与低空经济之间的关系和内在联系。立足西藏自治区低空经济发展的实际情况,客观评价低空产业发展现状,深入剖析存在的难点问题,灵活运用新质生产力的方法论,从强化科技创新、促进产业融合、加强要素供给等方面,提出针对西藏的低空经济高高原发展策略,推动实现低空产业的高质量发展。 展开更多
关键词 新质生产力 西藏自治区 低空经济 高高原发展策略
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高原型无人机活塞发动机涡轮增压器匹配研究
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作者 赵凯绅 杨广宾 +3 位作者 胡崇波 郭万山 齐国海 翟磊 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第1期105-112,共8页
目的为了研究利用汽车发动机开发低成本民用航空无人机活塞发动机的应用价值,方法提出基于汽车涡轮增压发动机的高海拔性能劣化补偿目标的开发方法。选取某型车用活塞式涡轮增压发动机,分析变海拔环境下的增压器-发动机匹配条件,评估汽... 目的为了研究利用汽车发动机开发低成本民用航空无人机活塞发动机的应用价值,方法提出基于汽车涡轮增压发动机的高海拔性能劣化补偿目标的开发方法。选取某型车用活塞式涡轮增压发动机,分析变海拔环境下的增压器-发动机匹配条件,评估汽车涡轮增压发动机在无人机飞行包线的边界内性能变差程度。通过目标海拔高度条件下的仿真计算,获得新涡轮增压器的目标增压压比和发动机进气流量。以此计算结果为目标新增压器的性能边界,选定某型号涡轮增压器,其性能输出特性能够覆盖该发动机作为无人机动力的进气目标增压压力和流量。在平原和高高原条件下开展无人机飞行性能验证,对新开发增压器的压气叶轮和涡轮叶轮产生的压比、膨胀比以及各自的折合流量分别进行校核,分析无人机在不同海拔环境下的飞行测试数据。结果结果表明,新匹配的涡轮增压器在海拔4200 m的高高原条件下搭载试验发动机,压气机压比为3.2,换算流量0.092 kg/s,运行区间在增压器叶轮的MAP包络线以内,能够使无人机达到28.2%的悬停有效载荷比,性能达到高高原载重飞行的技术要求。结论利用汽车涡轮增压发动机,按照无人机飞行包线内工况,重新匹配涡轮增压器的压气机,并校核涡轮机运行工况,能够实现满足民用航空无人机对高高原低空载重飞行性能的基本要求,匹配方法为新产品开发应用提供了理论指导。 展开更多
关键词 涡轮增压器 活塞发动机 高高原条件 低空无人机
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亚临界水环境下川西糜棱岩水-热腐蚀效应研究
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作者 周书涛 孙强 +3 位作者 耿济世 陈应涛 张慧婷 胡鑫 《工程地质学报》 CSCD 北大核心 2024年第3期851-861,共11页
位于青藏高原东部的川西构造带分布有高温地热资源,但同时也是地震活动多发区。为探究地热流体对断层岩石的腐蚀损伤,本文对川西金河-箐河断裂带上的糜棱岩开展100~350℃亚临界水环境(100~374℃,饱和蒸汽压0.1~22.1MPa)下的水-岩相互作... 位于青藏高原东部的川西构造带分布有高温地热资源,但同时也是地震活动多发区。为探究地热流体对断层岩石的腐蚀损伤,本文对川西金河-箐河断裂带上的糜棱岩开展100~350℃亚临界水环境(100~374℃,饱和蒸汽压0.1~22.1MPa)下的水-岩相互作用试验,通过电感耦合等离子体质谱仪(ICP-MS)和低温氮气吸附实验(LTNA)分析了反应后溶液成分和岩石孔隙结构随温度的变化规律。研究结果表明,川西糜棱岩Si的溶解速率在100~350℃范围内与水-岩作用温度呈正相关,350℃时溶解速率是100℃的10.97倍,而Na、Ca、K、Al和Mg等金属元素的溶解速率远低于Si。在长期水-热腐蚀下,糜棱岩Si元素的大量析出和硅酸盐矿物的分解会破坏岩石的孔隙结构,伴随微孔、中孔的萌生和发育,糜棱岩总孔体积由25℃时的0.00541cm^(3)·g^(-1)升高到350℃的0.00659cm^(3)·g^(-1),且比表面积随热处理温度的升高呈上升趋势,这会加强水与糜棱岩的接触,从而导致岩石的进一步劣化。本项研究结果为探究糜棱岩在亚临界水环境下的水-热腐蚀机制和地热流体影响断层稳定性提供了一定的见解。 展开更多
关键词 青藏高原东部 糜棱岩 高温水-岩相互作用 元素溶解 孔隙结构
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