80a-Oscillation of Summer Rainfall over the East Part of China and East-Asian Summer Monsoon

Relationship between summer rainfall over the east part of China and East-Asian Summer Monsoon (EASM) was studied based on the summer rainfall grade data set from 1470 to 1999 and the rain gauge data set from 1951 to 1999 over the east part of China, and sea level pressure (SLP) data for the period of 1871-2000. A distinct 80a-oscillation of summer rainfall was found over North China (NC), southern part of Northeast China, over the middle and lower reaches of the Yangtze River (YR) and South China (SC). The 80a oscillation of summer rainfall over NC was varied in phase with that over SC, and was out of phase to that along the middle and lower reaches of the Yangtze River. Summer rainfall over NC correlated negatively with the SLP averaged for the area from 105 degreesE to 120 degreesE, and from 30 degreesN to 35 degreesN, but positively to that for the area from 120 degreesE to 130 degreesE, and from 20 degreesN to 25 degreesN. Therefore, an index of EASM was defined by the difference of averaged SLP over the two regions. The summer rainfall over NC was greater than normal when the EASM was strong, and while drought occurred along the middle and lower reaches of the Yangtze River. The drought was found over NC, and flood along the middle and lower reaches of the Yangtze River when the EASM was close to normal. Finally, the interdecadal variability of EASM was studied by using of long term summer rainfall grade data set over NC for the past 530 years.

Analysis of the severe group dust storms in eastern part of Northwest China

Based on the available original dust storm records from 60 meteorological stations, we discussed the identification standard of severe dust storms at a single station and constructed a quite complete time series of severe group dust storms in the eastern part of Northwest China in 1954–2001. The result shows that there were 99 severe group dust storms in this region in recent 48 years. The spatial distribution indicates that the Alax Plateau, most parts of the Ordos Plateau and most parts of the Hexi Corridor are the main areas influenced by severe group dust storms. In addition, the season and the month with the most frequent severe group dust storms are spring and April, accounting for 78.8% and 41.4% of the total events respectively. During the past 48 years the lowest rate of severe group dust storms occurred in the 1990s. Compared with the other 4 decades, on the average, the duration and the affected area of severe group dust storms are relatively short and small during the 1990s. In 2000 and 2001, there were separately 4 severe group dust storms as the higher value after 1983 in the eastern part of Northwest China.

SIMPLE ECOSYSTEM MODEL OF THE CENTRAL PART OF THE EAST CHINA SEA IN SPRING

This paper’s simple ecological model to simulate the ecosystem variation and the vertical carbon flux in the central part of the East China Sea in spring, inter-reated the phytoplankton, zooplankton,autotrophic and heterotrophic bacterioplankton, nitrate, and dissolved organic carbon (DOC) in a run lasting 90 days. Except for DOC, because of poor observation precision,the major seasonal features of the vertical distribution for these components can be simulated by this model. The results show that spring bloom is just a short period of 1-2 weeks and that deposit carbon flux at the bottom interface is about 200 mg /m2 ·d in the first 20 days and then reaches its maximum of 1500mg/m2·d about 2 months later after the spring bloom.

Palaeorunoff estimations achieved from palaeoclimatic information for the southwest part of the North China Plain: an attempt to apply a climatological approach to palaeohydrology

Palaeoclimatic scenario projecting annual temperature and annual precipitation is firstly formalized with data available and speculations for the southwest part of the North China Plain (35— 37°N, 115—119°E) during the last 25000 years. Then, with three regression equations relating annual runoff to annual precipitation and derived with data of modern hydrological and meteorological records, values of annual runoff are calculated in terms of the corresponding values of annual precipitation from this palaeoclimatic scenario for this region during this temporal interval. These results indicate that runoff is the most during 8000—3000 a B.P. and the least during 25000—12000 a B.P.; runoff occurring during 12000—8000 a B.P. and during 3000—0 a B.P. is less than the one occurring during 8000—3000 a B.P. and more than the one occurring during 25000—12000 a B.P.; and the runoff occurring during 25000—12000 a B.P., 12000—8000 a B.P., and 3000—0 a B.P. is respectively 43, 46 and 66 percent of the one occurring during 8000—3000 a B.P. Values of bankfull discharge for palaeochannels of the Yellow River flowing in this region during the same interval are calculated from available estimates of slope of stream bed of these palaeochannels with a regression equation relating bankfull discharge to slope of stream bed and ratios of bankfull discharge are further calculated from these values for different groups of palaeochannel formed during different time spans embraced in this interval. To conduct a cross check, these values and ratios of bankfull discharge are compared to the corresponding values and ratios of runoff occurring during roughly the same time spans. The same direction and similar relative magnitude of changes of the surface water occurring in this region during the last 25000 years are indicated by these comparisons.

Numerical simulation of the crustal stress field by using data of deep geophysical exploration in the northern part of North China

DSS data of the last twenty years and more in the northern part of North China are further interpreted, and combined with other geological and geophysical data, the crustal model for the 3 D finite element method is built after straticulate crustal structure and elastic mechanics parameters are obtained. Referring to regional tectonic stress field and taking the effect of gravity into account, the paper constrains properly the model boundary and then computes the displacement of each nodal point and the strain and stress of each element by using the program from the 3 D linear elastic finite method. The relationship between the distribution feature of the crustal stress field and seismicity is discussed on the basis of analyzing contour maps of maximum principal compressive stress in the upper, middle and lower crusts.

Rb-Sr Isotopic Chronology of the Au-Bearing Quartz Veins in Gold Deposits in the Eastern Part of North China Platform

In the eastern part of China there had occurred large\|scale gold mineralization during the Mesozoic, resulting in a large number of important gold ore\|concentrated areas. In this paper we have selected some isotope data (including four gold deposits previously studied and two gold deposits in this work) of Au\|bearing quartz veins of the representative gold deposits in six important gold ore\|concentrated areas in the periphery of the North China Platform and calculated their metallogenic ages using the method of Ludwig (2.90 version). The results show that the representative gold deposits in the six gold ore\|concentrated areas were formed during the Mesozoic.

Upper mantle P wave velocity structure of the northern part of China and Mongolia

The average upper mantle P wave velocity structure and lateral heterogeneity in the northern part of China and Mongolia are investigated by waveform inversion of broadband body waveform data recorded by CDSN and digital stations around China. The average model has a low P wave velocity lid (about 7.8～8.0 km·s -1 ) with thickness about 60 km, and two discontinuities with velocity jumps of 0.29 km·s -1 and 0.55 km·s -1 at depth of 410 km and 665 km respectively. In the Jungger basin, the P wave velocity of uppermost mantle is about 7.7 km·s -1 . The lid thickness (90～100 km) and velocity gradient (average gradient is greater than 0.005 5/s) are large. At the depth of 140 km the P wave velocity reaches to 8.2 km·s -1 . Near in Baikal, the lid is about 30 km thick with average P wave velocity of 8.00～8.05 km·s -1 .

Characteristics of a Short-Term and Imminent Earthquake Precursor Field in the Northern Part of North China and Numerical Simulation of Source Process

According to studies of more than 20 earthquakes with MS≥5.0 in North China, seven features of the short-term and imminent earthquake precursors have been summarized in this paper. At the same time, taking the short-term and imminent earthquake stage as the physical process of a source’s medium softening and fault creep, we calculated temporal variation of mean stress, maximum shear stress, body strain, and pore pressure in some certain points (supposed stations) in the source area and its adjacent area by using an anisotropic and nonlinear source model and a finite element method. According to an analysis of these theoretical curves, we conclude that the short-term and imminent earthquake precursors have such characteristics as complex shapes, exponential growth of the precursor number with tune, and precursors’ migration from the outside area to the source area, which to a certain extent reveal the cause of the characteristics of the short-term and imminent earthquake precursor field.

RCEP对中日汽车及零部件产出和贸易的影响——基于动态递归GTAP的模拟分析

《区域全面经济伙伴关系协定》(RCEP)首次达成了中、日两国之间双边关税的减让安排协议。中国是全球最大的汽车生产和消费市场,日本是中国汽车的第一大进口来源国。本文通过分析中、日两国汽车及零部件产品贸易的现状及特征,总结RCEP协定下中日汽车及零部件的具体降税安排,并采用GTAP模型模拟分析了RCEP对中日汽车及零部件产出和贸易的影响。研究发现:近二十年来,中、日两国汽车及零部件双边贸易大幅增长;日本的汽车产品具有较强的国际竞争力,且对中国贸易互补性较强。RCEP关税减免和消除技术性贸易壁垒等措施将显著促进中、日两国汽车及零部件产出和贸易的增长。中国企业要充分利用RCEP原产地累积规则,增加对日本汽车零部件产品的出口额,并积极扩大新能源汽车出口。

中西部地区老年人社会参与、自我管理、社会凝聚力与健康的关系

目的:探讨中西部地区老年人社会参与、自我管理、社会凝聚力与健康的关系。方法:基于2017年中国综合社会调查数据,运用Ordinal Logit嵌套模型和KHB分解法检验非正式参与和正式参与对中西部地区老年人健康的影响效应和作用机制。结果:非正式参与和正式参与对中西部地区老年人健康有显著正向影响,这一影响在男性以及已婚老年人中更明显。自我管理和社会凝聚力是社会参与作用机制的中介变量,但其作用机制存在维度和结构差异。自我管理的中介效应在男性中显著,社会凝聚力的中介效应在女性中显著。自我管理的中介效应在已婚和未婚老年人中均显著,社会凝聚力的中介效应仅在已婚老年人中显著。结论:应通过落实政策、动员政府部门和医护力量等引导中西部老年人进行社会参与,进而提升其健康水平。

基于印度洋海温信号的我国西北地区东部夏季降水组合降尺度预测方法研究

利用国家气候中心第二代气候模式预测业务系统(BCC-CPSv2)预测产品,引入印度洋海温信号,采用组合降尺度方法建立了西北地区东部汛期降水预测模型。该预测模型对1991—2017年西北地区东部夏季降水的回报技巧较BCC-CPSv2预测技巧显著提高,空间相关系数由0.42提高到0.75,均方根误差明显减小,最多下降达80%。预测模型对降水空间分布型的预测能力较好,很好地回报了典型年份(1987年和2010年)夏季的降水距平百分率分布。通过抓住气象变量的空间分布特征,组合降尺度方法可以修正动力模式产品的预测误差,为西北地区东部夏季降水预测提供科学依据和技术支持,具有较好的应用前景。

历史主动精神推进中国式现代化:价值耦合、现实图景、践行路径

实现现代化是各国人民的普遍追求,亦是人类文明发展的普遍趋势。经过长期探索,中国共产党带领中国人民实现了中国式现代化从“世界失我”到“世界有我”再到“世界向我”的跃迁。这一跃迁离不开历史主动精神的支撑。历史主动精神内含的价值要义与推进中国式现代化具有高度的价值耦合性。其中,把握历史规律的科学精神是推动中国式现代化的题中之义,尊重人民的主体精神是推动中国式现代化的必然诉求,未雨绸缪的预见精神是推进中国式现代化的战略导向,勇毅前行的担当精神是推进中国式现代化的现实保障。百余年来,中国共产党带领中国人民以强烈的历史主动精神书写了中国式现代化从探索现代化之路到开创中国式现代化新局面的恢弘叙事。如今,站在新征程上,需要继续发扬历史主动精神,加强和改进党的建设,推进马克思主义的守正创新,坚持和发展中国特色社会主义,推进中国式现代化实现新突破。

Purchase-oriented Classification Model of the Spare Parts of Agricultural Machinery

Based on the classification of spare parts and the research results of the demand of spare parts,a three-dimensional classification model of spare parts of agricultural machinery is established,which includes the application axis sorted by technical characteristics,the cost axis classified by ABC method,and the demand axis classified by the demand of the spare parts of agricultural machinery.These dimension axes represent different factors,and the application of factors in purchase is analyzed.Guiding value of each dimension axis is summarized in the field of the spare parts purchase;and corresponding strategy instruction is put forward.Integrated application of these strategies by model makes the purchase have more realistic operational meaning.Application field of the three-dimensional model of spare parts is discussed;and the direction for further research is pointed out.

Sedimentary Features of Shallow Ancient River Channels on the Northern Shelf of the South China Sea

Quaternary buried ancient river channels are widespread in the shallow-level sediments of the northern shelf of the South China Sea. The sedimentary sequence mainly of fluvial deposits comprise an important component part of the low-stand system tract and transgressive system tract in the study region. The plannar variation and spatial association of the sedimentary features such as incised valley fillings, deltaic foreset wedges and block slides of shelf-marginal fans reflect the palaeogeographic environment during the fall of the regional sea level in the northern part of the South China Sea. Based on the high-resolution seismic reflection data and gelogical data from boreholes, the present paper makes an integrated interpretation of the Quaternary ancient river channels in the shallow sediments of the study area, studies the sedimentary features of the ancient channels such as their spatial distribution, seismic facies reflection indicators, sedimentary facies and sand -body types, and discusses their formational setting and evolutionary model, with the main purpose to render a service to the hydrocarbon resources exploration and development and marine engineering in the northern shelf of the South China Sea.

TECTONIC EVOLUTION OF THE GARZE—LITANG PLATE JUNCTION, WITH PARTICULAR REFERENCE TO THE GOLD DEPOSITS

Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to Muli ,Sichuan ,with a width of 5～35km .The junction is located in the arcuate turning part of the Alpine—Himalayan—Indosinian Tethyan tectonic domain ,which lies in the structural transition position between the Yangtze plate and the Yidun area . The plate junction represents an important tectonic belt ,which is a composed of a gold mineralization belt in the east Tethyan tectonic domain.(1) Garze—Litang plate junction may be divided into the following structural units:ductile shear zone and fracture system, Paleozoic nappes ,ophiolite \|tectonic blocks,flysch formation in passive continental margin (Triassic Xikang group ),forearc sedimentary formation in active margin (Triassic Yidun group),and such boundary geological bodies as granitoids ,faulted basins and Tertiary nappes.

西北中东部ECMWF-HR云量预报产品与FY-2G云量产品的对比

为了了解ECMWF-HR模式云量预报产品在西北中东部地区的精度,利用2019年10月至2020年9月共计12个月的FY-2G卫星总云量反演产品,对西北地区中东部同时段的ECMWF-HR总云量预报产品进行对比分析,并选取3个典型区分析ECMWF-HR总云量预报偏差的日变化特征。结果表明,ECMWF-HR模式对西北地区中东部总云量的预报偏差白天较小,夜间偏差增大约10%~20%。总云量预报偏差具有明显的季节特征,夏半年ECMWF-HR模式云量预报整体偏多且偏差空间分布均匀;冬半年总云量预报有区域性特征,祁连山区西段明显偏低,甘肃和陕西南部明显偏多,其他大部地区的预报偏差低于夏半年。总体来说,ECMWF-HR模式总云量预报稳定可信,但在祁连山西段和甘肃与陕西南部2个明显异常区域需进行偏差订正。前者需要在模式预报基础上调高10%~30%,后者需要降低20%~30%;订正后的总云量预报与卫星反演结果较为接近,平均绝对偏差约4.5%,且与卫星反演结果具有相似的日变化特征。

高碳气置换高烃气实验及机理评价

中国南海西部某气田深层气组为高碳气藏,浅层气组为高烃气藏。为有效提高高烃气藏采收率,增大经济效益,开展高碳气置换高烃气机理室内实验,研究高碳气置换高烃气后气体组分及溶解度变化情况,以及置换后高烃气藏提高采收率的效果及影响因素结果表明:使用高碳气替换高烃气后,高碳气能够置换地层束缚水中的高烃气,游离CH_(4)增加,在低注高采、倾角较大和岩心高渗透率等储层条件下进行长岩心驱替,CH_(4)累计采出程度更高,采出程度可提高4.5%。该研究可对中国高烃气藏高效开发、高碳气藏中CO_(2)埋存方式评价提供理论参考。

RCEP对中国汽车及零部件产出和贸易的影响——基于动态递归GTAP的模拟分析

中国是全球汽车产量最大的国家,RCEP的生效实施将对中国汽车及零部件的产出和贸易产生重要影响。通过分析中国与RCEP各成员国汽车及零部件的贸易现状及竞争与互补关系,运用动态递归GTAP模型模拟分析了RCEP对中国汽车及零部件产出和贸易的影响。研究发现,中国汽车及零部件贸易呈逐年上升态势,中国在部分汽车零部件产品上具有比较优势,且与RCEP成员国的贸易互补性较强。RCEP的关税减免将使中国汽车的产出与进出口额显著增加,但减少技术性贸易壁垒和提升互联互通、投资和劳动力等因素对中国汽车及零部件贸易的影响更为显著。中国企业要充分利用RCEP的降税安排,提升汽车产品的国际竞争力,积极扩大汽车零部件产品及电动车的出口,并做好应对贸易摩擦的准备。

后全球化时代消费电子全球供应链分布变化及对我国的启示——基于苹果零部件供应商考察

后全球化时代,消费电子全球供应链在发生新变化,并被不断重塑。基于2018和2021年苹果零部件供应商数据,运用赫芬达尔指数、区位熵以及分布数量占比等方法,在分析苹果零部件全球供应链分布特征基础上,对比疫情前后苹果零部件全球供应链分布变化、重点领域供应链分布变化以及供应链在中国各省市分布变化等,综合透视后全球化时代消费电子全球供应链的变化特征与新近趋势。研究发现:首先,苹果零部件全球供应链集中分布于中国、日本、美国、韩国和中国台湾等少数国家和地区。对比疫情前后,发现核心零部件环节回归中国台湾和韩国的趋势明显,同时增加了向东南亚的布局,大规模退出中国和回归美国的趋势并不显著。其次,芯片设计与制造环节呈现进一步向美国、中国、中国台湾、韩国、新加坡、马来西亚等地集中趋势;液晶显示及触控环节的分布尽管以中国和日本为双核,但因在韩国、越南和美国分布数量增加导致呈现一定分散势头;尽管中国在组装代工及包装印刷环节独具分布数量优势,但越南表现出较强分流趋势;再次,苹果零部件全球供应链在中国分布呈现“核心-外围”格局;疫情后,广东和江苏的“双核”地位有所下降,上海地位上升明显,且内蒙古和云南开始切入苹果零部件全球供应链;第四,外资供应商在中国分布数量总体下降,主要是因非核心环节分布数量减少导致,核心环节分布较为稳定。最后,从提升在供应链体系中的控制力、构建自主可控的供应链体系以及构建新型合作关系三方面提出中国应对变化策略。