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12018 Chinese Pediatric Cardiology Society(CPCS) guideline for diagnosis and treatment of syncope in children and adolescents显示文摘Syncope belongs to the transient loss of consciousness(TLOC), characterized by a rapid onset, short duration, and spontaneous complete recovery. It is common in children and adolescents, accounting for 1% to 2% of emergency department visits.Recurrent syncope can seriously affect children's physical and mental health, learning ability and quality of life and sometimes cardiac syncope even poses a risk of sudden death. The present guideline for the diagnosis and treatment of syncope in children and adolescents was developed for guiding a better clinical management of pediatric syncope. Based on the globally recent development and the evidence-based data in China, 2018 Chinese Pediatric Cardiology Society(CPCS) guideline for diagnosis and treatment of syncope in children and adolescents was jointly prepared by the Pediatric Cardiology Society, Chinese Pediatric Society, Chinese Medical Association(CMA)/Committee on Pediatric Syncope, Pediatricians Branch, Chinese Medical Doctor Association(CMDA)/Committee on Pediatric Cardiology, Chinese College of Cardiovascular Physicians, Chinese Medical Doctor Association(CMDA)/Pediatric Cardiology Society, Beijing Pediatric Society, Beijing Medical Association(BMA). The present guideline includes the underlying diseases of syncope in children and adolescents, the diagnostic procedures, methodology and clinical significance of standing test and headup tilt test, the clinical diagnosis vasovagal syncope, postural orthostatic tachycardia syndrome, orthostatic hypotension and orthostatic hypertension, and the treatment of syncope as well as follow-up.Cheng Wang Yaqi Li Ying Liao Hong Tian Min Huang Xiangyu Dong Lin Shi Jinghui Sun Hongfang Jin Junbao Du Jindou An Jie Chen Mingwu Chen Qi Chen Sun Chen Yonghong Chen Zhi Chen Adolphus Kai-tung Chau Junbao Du Zhongdong Du Junkai Duan Hongyu Duan Xiangyu Dong Lin Feng Lijun Fu Fangqi Gong Yonghao Gui Ling Han Zhenhui Han Bing He Zhixu He Xiufen Hu Yimin Hua Guoying Huang Min Huang Ping Huang Yujuan Huang Hongfang Jin Mei Jin Bo Li Fen Li Tao Li Xiaohui Li Xiaoyan Liu Yan Li Haitao Lv Tiewei Lv Zipu Li Luyi Ma Silin Pan Yusheng Pang Hua Peng Yuming Qin Jie Shen Lin Shi Kun Sun Jinghui Sun Hong Tian Jie Tian Cheng Wang Hong Wang Lei Wang Jinju Wang Wendi Wang Yuli Wang Rongzhou Wu Tianhe Xia Yanyan Xiao Chunhong Xie Yanlin Xing Zhenyu Xiong Baoyuan Xu Yi Xu Hui Yan Shiwei Yang Qijian Yi Xia Yu Xianyi Yu Yue Yuan Hongyan Zhang Huili Zhang Li Zhang Qingyou Zhang Xi Zhang Yanmin Zhang Zhiwei Zhang Cuifen Zhao Bin Zhou Hua Zhu 2018Science Bulletin2018,63,23:54
2Impacts and Utilization of Electric Vehicles Integration Into Power Systems显示文摘HUZechun SONG Yonghua XU Zhiwei LUO Zhuowei ZHAN Kaiqiao JIA Long 2012中国电机工程学报2012,32,4:49
3New omega vortex identification method显示文摘A new vortex identification criterion called W-method is proposed based on the ideas that vorticity overtakes deformation in vortex.The comparison with other vortex identification methods like Q-criterion and λ_2-method is conducted and the advantages of the new method can be summarized as follows:(1) the method is able to capture vortex well and very easy to perform;(2) the physical meaning of W is clear while the interpretations of iso-surface values of Q and λ_2 chosen to visualize vortices are obscure;(3)being different from Q and λ_2 iso-surface visualization which requires wildly various thresholds to capture the vortex structure properly, W is pretty universal and does not need much adjustment in different cases and the iso-surfaces of W=0.52 can always capture the vortices properly in all the cases at different time steps, which we investigated;(4) both strong and weak vortices can be captured well simultaneously while improper Q and λ_2 threshold may lead to strong vortex capture while weak vortices are lost or weak vortices are captured but strong vortices are smeared;(5) W=0.52 is a quantity to approximately define the vortex boundary. Note that, to calculate W, the length and velocity must be used in the non-dimensional form. From our direct numerical simulation, it is found that the vorticity direction is very different from the vortex rotation direction in general 3-D vortical flow,the Helmholtz velocity decomposition is reviewed and vorticity is proposed to be further decomposed to vortical vorticity and non-vortical vorticity.ChaoQun Liu YiQian Wang Yong Yang ZhiWei Duan 2016Science China(Physics,Mechanics & Astronomy)2016,59,8:49
4The bHLH Transcription Factor MYC3 Interacts with the Jasmonate ZIM-Domain Proteins to Mediate Jasmonate Response in Arabidopsis显示文摘Arabidopsis Jasmonate ZIM 域蛋白质(JAZ ) 充当复杂的 SCFCOI1 的底层镇压他们的下游地指向,它为调整 JA 的植物开发和防卫是必要的。bHLH 抄写因素 MYC2 被发现 JA 回答包括与 JAZ 交往并且调停 JA 禁止的根生长。这里,我们识别了直接由它的 N 终端区域的优点与 JAZ 交往了调整 JA 回答的另一 bHLH 抄写因素 MYC3。有 MYC3 的 overexpression 的转基因的植物在 JA 禁止的根延伸和幼苗开发展出了超敏性。交往 JAZ 模式和 MYC3 的导致 JA 的表示模式从 MYC2 的那些是可区分的。我们推测那 MYC3, MYC2 可以在 JA 回答的规定有冗余而且可区分的功能。Zhiwei Cheng Li Sun Tiancong Qi Bosen Zhang Wen Peng Yule Liu Daoxin Xie 2011Molecular Plant2011,4,2:35
5Chinese deserts and sand fields in Last Glacial Maximum and Holocene Optimum显示文摘The Last Glacial Maximum (LGM, c. 26-16 ka) and the Holocene Optimum (HO, c. 9-5 ka) were characterized by cold-dry and warm-wet climates respectively in the recently geological Earth. How Chinese deserts and sand fields responded to these distinctive climatic changes is still not clear, however. To reconstruct environments of the deserts and sand fields during the LGM and HO is helpful to understand the forcing mechanisms of environment change in this arid region, and to test paleoclimatic modeling results. Through our long-term field and laboratory investigations, 400 optically stimulated luminescence (OSL) ages and more than 100 depositional records in the Chinese deserts and sand fields were obtained; on the basis of these data, we reconstruct spatial distributions of the deserts and sand fields during the LGM and HO. Our results show that the sand fields of Mu Us, Hunshandake, Horqin and Hulun Buir in northern and northeastern China had expanded 25%, 37%, 38% and 270%, respectively, during the LGM; the sand fields of Gonghe in the northeastern Qinghai-Tibetan Plateau had expanded 20%, and the deserts of Badain Jaran, Tengger in central northern China had expanded 39% and 29% separately during the LGM; the deserts of Taklimakan, Gurbantünggüt and Kumtag in northwestern China had expanded 10%-20% respectively, compared to their modern areas. On the other hand, all of the sand fields were nearly completely covered by vegetation during the HO; the deserts in northwestern and central northern China were reduced by around 5%-20% in area during this time. Lakes in this arid region were probably expanded during the HO but this conclusion needs more investigation. Compared with the geological distributions of deserts and sand fields, human activity has clearly changed (expanded) the area of active sand dunes at the present time. Our observations show that environmental conditions of Chinese deserts and sand fields are controlled by regional climate together with human activity.LU HuaYu YI ShuangWen XU ZhiWei ZHOU YaLi ZENG Lin ZHU FangYing FENG Han DONG LiNa ZHUO HaiXin YU KaiFeng MASON Joseph WANG XiaoYong CHEN YingYong LU Qi WU Bo DONG ZhiBao QU JianJun WANG XunMing GUO ZhengTang 2013Chinese Science Bulletin2013,58,23:40
642,573 cases of hepatectomy in China: a multicenter retrospective investigation显示文摘Hepatectomy is currently routinely performed in most hospitals in China. China owns the largest population of liver diseases and the biggest number of liver resection cases. A nationwide multicenter retrospective investigation involving 112 hospitals was performed, and focused on liver resection for patients with hepatocellular carcinoma(HCC). 42,573 cases of hepatectomy were enrolled, and 18,275 valid cases of liver resection for HCC patients were selected for statistical analysis. The epidemiology of HCC, distribution of hepatectomy, postoperative complications and prognosis were finally analyzed. In the 18,275 HCC patients,81% had hepatitis B virus infection and 10% had hepatitis C virus infection. 38% of the HCC patients had normal Alphafetoprotein(AFP) level, and other 35% had an AFP level lower than 400 ng mL^(-1). In the study period, 97% of the hepatectomy for HCC were treated with open surgery, and 23.81% had vascular exclusion techniques. The operation time was(191.7±105.6) min,the blood loss was(546.0±562.8) m L, and blood transfusion was(543.0±1,035.2) m L. The median survival for HCC patients was 631 days, with 1-, 3-, and 5-year overall survival of 73.2%, 28.8% and 19.6%, respectively. Liver cirrhosis, multiple nodules,tumor thrombosis and high AFP level were risk factors that affect postoperative survival.Binhao Zhang Bixiang Zhang Zhiwei Zhang Zhiyong Huang Yifa Chen Minshan Chen Ping Bie Baogang Peng Liqun Wu Zhiming Wang Bo Li Jia Fan Lunxiu Qin Ping Chen Jingfeng Liu Zhe Tang Jun Niu Xinmin Yin Deyu Li Songqing He Bin Jiang Yilei Mao Weiping Zhou Xiaoping Chen 2018Science China(Life Sciences)2018,61,6:39
7Klf7 modulates the differentiation and proliferation of chicken preadipocyte显示文摘Kr?Zhiwei Zhang 2013Acta Biochimica et Biophysica Sinica2013,45,4:34
8Large-scale atmospheric singularities and summer long-cycle droughts-floods abrupt alternation in the middle and lower reaches of the Yangtze River显示文摘The daily precipitation data at 720 sta- tions over China for the 1957―2003 period during summer (May―August) are used to investigate the summer subseasonal long-cycle droughts-floods abrupt alternation (LDFA) phenomenon and a long-cycle droughts-floods abrupt alternation index (LDFAI) in the middle and lower reaches of the Yangtze River (MLYRV) is defined to quantify this phenomenon. The large-scale atmospheric circula- tion features in the anomalous LDFA years are ex- amined statistically. Results demonstrate that the summer droughts-to-floods (DTF) in the MLYRV usually accompany with the more southward western Pacific subtropical high (WPSH), negative vorticity, strong divergence, descending movements develop- ing and the weak moisture transport in the low level, the more southward position of the South Asia high (SAH) and the westerly jets in the high level during May―June, but during July―August it is in the other way, northward shift of the WPSH, positive vorticity, strong convergence, ascending movements and strong moisture transport in the low level, and the northward shift of the SAH and the westerly jets in the high level. While for the summer floods-to-droughts (FTD) in the MLYRV it often goes with the active coldair mass from the high latitude, positive vorticity, strong convergence, ascending movement develop- ing and the strong moisture transport in the low level, and the SAH over the Tibetan Plateau in the high level, but during July―August it is often connected with the negative vorticity, strong divergence, de- scending movements developing and the weak moisture transport in the low level, the remarkable northward shift of the WPSH, the SAH extending northeastward to North China and the easterly jets prevailing in the high level over the MLYRV. In addi- tion, the summer LDFA in the MLYRV is of significant relationship with the Southern Hemisphere annual mode and the Northern Hemisphere annual mode in the preceding February, which offers some predictive signals for the summer LDFA forecasting in the MLYRV.WU Zhiwei LI Jianping HE Jinhai JIANG Zhihong 2006Chinese Science Bulletin2006,51,16:30
9Therapeutic potential of siRNA-mediated combined knockdown of the lAP genes (Livin, XIAP, and Survivin) on human bladder cancer T24 cells显示文摘Livin, apoptosis (XIAP ) 的 X 连接禁止者,和 Survivin 几乎是 apoptosis 的三个著名禁止者在癌症房间只过去表示并且为癌症治疗被认为有势力目标。在现在的学习,我们发现 Livin, XIAP,和 Survivin 同时在膀胱癌症房间被表示。我们推测了那 Livin, XIAP,和 Survivin 可能在房间生长和 apoptosis 上有 synergistic 效果。我们的结果证实了联合那所有这三基因击倒能 synergistically 禁止增长和高级膀胱癌症 T24 房间的转变能力并且把房间 apoptotic 敏感提升到化疗。而且,联合了 Livin, XIAP,和 Survivin 罐头击倒显著地增加许多活跃 caspase-3,活跃 caspase-7,活跃 caspase-9,和 cytosolic Smac。我们的调查结果暗示 Livin, XIAP,和 Survivin 的那联合 silencing 可以是一个有势力为膀胱癌症的多指向的基因治疗。Deyong Yang Xishuang Song Jianing Zhang Lin Ye Shujing Wang Xiangyu Che Jianbo Wang Zhiwei Zhang Lina Wang Wei Shi 2010Acta Biochimica et Biophysica Sinica2010,42,2:29
10OUT-OF-PLANE COMPRESSIVE PROPERTIES OF HEXAGONAL PAPER HONEYCOMBS显示文摘The compressive behaviour of paper honeycombs is studied by means of an experimental analysis. Experiment results show how geometry aspects of hexagonal paper honeycombs,e.g. the height of paper honeycomb,the thickness and length of honeycomb cell-wall,the drawing ratio of hexagonal honeycomb,affect the compressive properties of the paper honeycombs. It is in good agreement with the theory model. The constraint factor K of the critical buckling stress is mainly determined by the length of honeycomb cell-wall. It can be described as K=1.54 for B type paper honeycombs and K=3.32 for D type paper honeycombs. The plateau stress is the power exponent function of the thickness to length ratio of honeycomb cell-wall,and the experiment results show that the constant is 13.2 and the power exponent is 1.77. The research results can be used to characterize and improve efficiently the compressive properties of paper honeycombs.WANG Dongmei WANG Zhiwei 2007Chinese Journal of Mechanical Engineering2007,20,2:28
11Type V CRISPR-Cas Cpfl endonuclease employs a unique mechanism for crRNA-mediated target DNA recognition显示文摘Pu Gao Hui Yang Kanagalaghatta R Rajashankar Zhiwei Huang Dinshaw J Patel 2016Cell Research2016,26,8:28
12Validation of clinical significance of examined lymph node count for accurate prognostic evaluation of gastric cancer for the eighth edition of the American Joint Committee on Cancer(AJCC) TNM staging system显示文摘Objective: To validate the necessity of increasing the examined lymph node(ELN) count for enhancing the accuracy of prognostic evaluation of gastric cancer(GC) patients after curative gastrectomy in multiple medical centers of China.Methods: The clinicopathological data of 7,620 patients who underwent the curative resection for GC between2001 and 2011 were included to demonstrate whether the ELN count is indispensable for enhancing the accuracy of prognostic evaluation of GC patients after surgery. After a meticulous stratification by using the cut-point survival analysis, all included 7,620 patients were allocated into three groups as: less than 16(<16), between 16 and30(16-30), and more than 30(>30) ELNs. Survival differences among various subgroups of GC patients were analyzed to assess the impact of the ELN count on the stage migration in accordance with the overall survival(OS)of GC patients.Results: Survival analyses revealed that the ELN count was positively correlated with the OS(P=0.001) and was an independent prognostic predictor(P<0.01) of 7,620 GC patients. Stratum analysis showed that the accuracy of prognostic evaluation could be enhanced when the ELN count was no less than 16(≥16) for node-negative patients and >30 for node-positive patients. Stage migrations were mainly detected in the various subgroups of patients with specific pN stages as follows: pN0 with 16-30 ELNs(pN0_(16-30)) and pN0 with >30 ELNs(pN0_(>30)), pN0 with <16 ELNs(pN0_(<16)) and pN1_(>30), pN1_(<16) and pN2_(16-30), pN1_(16-30) and pN2_(>30), pN3a_(<16) and pN3b_(16-30), and pN3a_(<16) and pN3b_(>30). These findings indicate that increasing the ELN count is a prerequisite to guarantee precisely prognostic evaluation of GC patients.Conclusions: The ELN count should be proposed to be >30 for acquiring the accurate prognostic evaluation for GC patients, especially for node-positive patients.Jingyu Deng Jinyuan Liu Wei Wang Zhe Sun Zhenning Wang Zhiwei Zhou Huimian Xu Han Liang 2018Chinese Journal of Cancer Research2018,30,5:27
13Growing seismicity in the Sichuan Basin and its association with industrial activities显示文摘In the Sichuan Basin,seismic activity has been low historically,but in the past few decades,a series of moderate to strong earthquakes have occurred.Especially since 2015,earthquake activity has seen an unprecedented continuous growth trend,and the magnitude of events is increasing.Following the M5.7 Xingwen earthquake on 18 Dec.2018,which was suggested to be induced by shale gas hydraulic fracturing,a swarm of earthquakes with a maximum magnitude up to M6.0 struck Changning and the surrounding counties.Questions arose about the possible involvement of industrial actions in these destructive events.In fact,underground fluid injection in salt mine fields has been occurring in the Sichuan Basin for more than70 years.Disposal of wastewater in natural gas fields has also continued for about 40 years.Since 2008,injection for shale gas development in the southern Sichuan Basin has increased rapidly.The possible link between the increasing seismicity and increasing injection activity is an important issue.Although surrounded by seismically active zones to the southwest and northwest,the Sichuan Basin is a rather stable region with a wide range of geological settings.First,we present a brief review of earthquakes of magnitude 5 or higher since 1600 to obtain the long-term event rate and explore the possible link between the rapidly increasing trend of seismic activity and industrial injection activities in recent decades.Second,based on a review of previous research results,combined with the latest data,we describe a comprehensive analysis of the characteristics and occurrence conditions of natural and injection-induced major seismic clusters in the Sichuan Basin since 1700.Finally,we list some conclusions and insights,which provide a better understanding of why damaging events occur so that they can either be avoided or mitigated,point out scientific questions that need urgent research,and propose a general framework based on geomechanics for assessment and management of earthquake-related risks.Xinglin LEI Jinrong SU Zhiwei WANG 2020Science China Earth Sciences2020,63,11:27
14Adakite-type sodium-rich rocks in Awulale Mountain of west Tianshan:Significance for the vertical growth of continental crust显示文摘The sodium-rich dacites and albite porphyries of Permian in the Awulale Mountain of west Tianshan have unique chemical and trace element signatures identical to adakite. These intermediate-acidic igneous rocks are characterized by high Na2O, Al2O3 and Sr contents and high Sr/Y and La/Y ratios (>40 and >20, respectively), and low Y and Yb contents, and strong depletion in HREE, and positive Eu anomaly. The (143Nd/144Nd)i is in the range from0.51236 to 0.51248 and the εNd(t) is positive value (+0.79-+3.11); the (87Sr/86Sr)i is in the range from 0.7052 to 0.7054. These Nd and Sr isotopic composition features indicate that the source rocks of these adakite-type rocks are from a weakly depleted mantle, or a depleted mantle, but was contaminated by the crustal materials. These adakite-type rocks were most likely derived from the partial melting of new underplated basaltic rocks under the conditions of amphibo-lite to eclogite transition in the postcollisional environment of North Xinjiang during the PermianXIONG Xiaolin ZHAO Zhenhua BAI Zhenghua MEI Houjun WANG Yixian WANG Qiang XU Jifeng Niu Hecai BAO Zhiwei 2001Chinese Science Bulletin2001,46,10:25
15Second harmonic generation in a high-Q lithium niobate microresonator fabricated by femtosecond laser micromachining显示文摘We report on second harmonic generation(SHG) in on-chip high-Q(>105) lithium niobate(Li Nb O3, LN) microresonators fabricated by femtosecond laser micromachining. We examine the efficiency of SHG with either a continuous-wave(CW) or an ultrashort pulsed pump laser. The normalized conversion efficiencies of SHG obtained with the CW and pulsed pump lasers are measured to be 1.35×10?5 m W?1 and 2.30×10?6 m W?1, respectively.LIN JinTian XU YingXin FANG ZhiWei WANG Min WANG NengWen QIAO LingLing FANG Wei CHENG Ya 2015Science China(Physics,Mechanics & Astronomy)2015,58,11:25
16Preoperative neutrophil-to-lymphocyte ratio plus platelet-to-lymphocyte ratioin predicting survival for patients with stage Ⅰ-Ⅱgastric cancer显示文摘Background:The preoperative neutrophil-to-lymphocyte ratio(NLR) and the platelet-to-lymphocyte ratio(PLR) are associated with poor prognosis of gastric cancer.We aimed to determine whether the combination of NLR and PLR(NLR-PLR) could better predict survival of patients after curative resection for stage Ⅰ-Ⅱ gastric cancer.Methods:We collected data from the medical records of patients with stage Ⅰ-Ⅱ gastric cancer undergoing curative resection between December 2000 and November 2012 at the Sun Yat-sen Cancer Center.The preoperative NLRPLR was calculated as follows:patients with both elevated NLR(≥2.1) and PLR(≥ 120) were given a score of 2,and patients with only one or neither were given a score of 1 or 0,respectively.Results:Kaplan-Meier analysis and log-rank tests revealed significant differences in overall survival(OS) among patients with NLR-PLR scores of 0,1 and 2(P < 0.001).Multivariate analysis showed that OS was independently associated with the NLR-PLR score[hazard ratio(HR) = 1.51,95%confidence interval(CI) 1.02-2.24,P = 0.039]and TNM stage(HR = 1.36,95%CI 1.01-1.83,P= 0.041).However,other systemic inflammation-based prognostic scores,including the modified Glasgow prognostic score,the prognostic nutritional index,and the combination of platelet count and NLR,were not.In TNM stage-stratified analysis,the prognostic significance of NLR-PLR was maintained in patients with stage Ⅰ(P < 0.001) and stage Ⅱ cancers(P= 0.022).In addition,the area under the receiver operating characteristic curve for the NLR-PLR score was higher than those of other systemic inflammation-based prognostic scores(P = 0.001).Conclusion:The preoperative NLR-PLR score is a useful predictor of postoperative survival in the patients with stage l-ll gastric cancer and may help identify high-risk patients for rational therapy and timely follow-up.Xiaowei Sun Xuechao Liu Jianjun Liu Shangxiang Chen Dazhi Xu Wei Li Youqing Zhan Yuanfang Li Yingbo Chen Zhiwei Zhou 2016Chinese Journal of Cancer2016,35,7:25
17Possible link between long-term and short-term water injections and earthquakes in salt mine and shale gas site in Changning,south Sichuan Basin, China显示文摘Late at night on 17 June 2019,a magnitude 6.0 earthquake struck Shuanghe Town and its surrounding area in Changning County,Sichuan,China,becoming the largest earthquake recorded within the southern Sichuan Basin.A series of earthquakes with magnitudes up to 5.6 occurred during a short period after the mainshock,and we thus refer to these earthquakes as the Changning M6 earthquake sequence(or swarm).The mainshock was located very close to a salt mine,into which for^3 decades fresh water had been extensively injected through several wells at a depth of 2.7–3 km.It was also near(within^15 km)the epicenter of the 18 December 2018 M5.7 Xingwen earthquake,which is thought to have been induced by shale gas hydraulic fracturing(HF),prompting questions about the possible involvement of industrial activities in the M6 sequence.Following previous studies,this paper focuses on the relationship between injection and seismicity in the Shuanghe salt field and its adjacent Shangluo shale gas block.Except for a period of serious water loss after the start of cross-well injection in 2005–2006,the frequency of earthquakes shows a slightly increasing tendency.Overall,there is a good correlation between the event rate in the Shuanghe area and the loss of injected water.More than 400 M≥3 earthquakes,including 40 M≥4 and 5 M≥5 events,had been observed by the end of August 2019.Meanwhile,in the Shangluo area,seismicity has increased during drilling and HF operations(mostly in vertical wells)since about 2009,and dramatically since the end of 2014,coincident with the start of systematic HF in the area.The event rate shows a progressively increasing background with some fluctuations,paralleling the increase in HF operations.More than 700 M≥3 earthquakes,including 10 M≥4 and 3 M≥5 in spatially and temporally clustered seismic events,are correlated closely with active fracturing platforms.Well-resolved centroid moment tensor results for M≥4 earthquakes were shown to occur at very shallow depths around shale formations with active HF,in agreement with some of the clusters,which occurred within the coverage area of temporary or new permanent monitoring stations and thus have been precisely located.After the Xingwen M5.7 earthquake,seismic activity in the salt well area increased significantly.The Xingwen earthquake may have created a unidirectional rupture to the NNW,with an end point close to the NW-trending fault of the Shuanghe earthquake.Thus,a fault in the Changning anticline might have terminated the fault rupture of the Xingwen earthquake,possibly giving the Xingwen earthquake a role in promoting the Changning M6 event.XingLin Lei ZhiWei Wang JinRong Su 2019Earth and Planetary Physics2019,3,6:24
18Inorganic chemical composition and source signature of PM2.5 in Beijing during ACE-Asia period显示文摘Aerosol samples for PM2.5 were collected in Beijing for 38 consecutive days from March to April 2001 using an IMPROVE Sampler. Concentrations of 20 elements in PM2.5 were determined using a PIXE method. Results show that the average mineral dust concentration of PM2.5 was 14.6 mg/m3 during the observation period. On the sand-dust event days of March 21 and April 10, dust PM2.5 mass concentrations were 62.4 and 54.1 mg/m3, respectively. These demonstrate that fine particle pollution by dust event in Beijing was very severe. The enrichment factors of S and Cu reached minimums on the dusty days and were high on the non-dusty days. It is considered that enrichment factors of elements in PM2.5, which are associated with human activities, can probably provide an effective method to distinguish local sources from external sources of dust. Factor analysis on the chemical composition in PM2.5 shows that sources of crustal matters, anthropogenic emission, and oil combustion contributed to PM2.5 levels in air in the springtime of 2001 in Beijing.ZHANG Renjian, XU Yongfu & HAN Zhiwei LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 2003Chinese Science Bulletin2003,48,10:24
19Geochronology and geochemistry of the Fangcheng Neoproterozoic alkali-syenites in East Qinling orogen and its geodynamic implications显示文摘Finding of Neoproterozoic syenites at Fangcheng in the northern Qinling region of the East Qinling orogen provides an important constraint on timing of tectonic transformation to extensional regime. The alkaline pluton consists mainly of nepheline syenite,aegirine syenite,and alkali-feldspar syenite. The syenites are of intermediate (SiO2=54%―62%),rich in alkali (K2O+Na2O=12%―15%),aluminum (Al2O3=16.81%―23.26%) and large ion lithophile elements (LILE),without any obvious Nb,Ta,Zr,and Hf anoma-lies. The Fangcheng syenites are geochemically characterized by relative enrichment of LREE,minor differentiation of HREE,significant negative Eu anomalies (Eu=0.13―0.23),less negative εNd(t) values of -1.37 to -3.90,young Nd model ages of 1364 to 1569 Ma,and high zircon saturation temperatures of 915 to 1044℃. The syenitic magmas probably originated from small proportion melting of upper mantle in an extensional regime of intraplate-anorogenic tectonic setting,and have been slightly contaminated by crustal materials during ascending and/or emplacement. LA-ICP-MS zircon U-Pb dating yields ages of 844.3±1.6 Ma (MSWD=0.86),suggesting that the Fangcheng alkaline syenites formed in the early Neo-proterozoic. They are the oldest Neoproterozoic alkaline rocks ever recognized in the Qinling orogen as well as in South China. This implies that the tectonic regime of the Qinling region would have transformed from post-collisional stretch to intraplate-anorogenic extension no later than 844 Ma.BAO ZhiWei WANG Qiang BAI GuoDian ZHAO ZhenHua SONG YaoWu LIU XiaoMing 2008Chinese Science Bulletin2008,53,13:22
20Study on the flow field and concentration characteristics of the multiple tandem jets in crossflow显示文摘The characteristics of single and multiple tandem jets(n=2,3,4) in crossflow have been investigated using the realizable k-ε model.The results of this model agree well with experimental measurements using PIV(Particle Image Velocimetry) or LIF(Laser Induced Fluorescence).We analyzed the calculated results and obtained detailed properties of velocity and concentration of the multiple jets in the pre-merging and post-merging regions.When the velocity ratio is identical,the bending degree of the leading jet is greater than that of the rear jets.The last jet penetrates deeper as the jet number increases,and the shielding effect of the front jet declines with jet spacing increase.Interaction of the jet and crossflow induces formation and development of a counter-rotating vortex pair(CVP).CVP makes the distribution of concentration appear kidney-shaped(except in the merging region),and maximum concentration is at the center of the counter-rotating vortex.Concentration at the CVP center is 1.03-1.4 times that of the local jet trajectory.Post-merging velocity and concentration characteristics differ from those of the single jet because of the shielding effect and mixing of all jets.This paper presents a unified formula of trajectory,concentration half-width and trajectory dilution,by introducing a reduction factor.LI ZhiWei HUAI WenXin QIAN ZhongDong 2012Science China(Technological Sciences)2012,55,10:22
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