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    题名 作者 年代 出处 被引量
1Prognostic value of systemic immune.inflammation index in patients with gastric cancer显示文摘Background:Inflammation-based indexes have been used to predict survival and recurrence in cancer patients.Systemic immune-inflammation index(Sll) was reported to be associated with prognosis in some malignant tumors.In the present study,we aimed to explore the association between Sll and the prognosis of patients with gastric cancer.Methods:We retrospectively analyzed data from 444 gastric cancer patients who underwent gastrectomy at the First Affiliated Hospital of Sun Yat-sen University between January 1994 and December 2005.Preoperative Sll was calculated.The Chi square test or Fisher's exact test was used to determine the relationship between preoperative Sll and clinicopathologic characteristics.Overall survival(OS) rates were estimated using the Kaplan-Meier method,and the effect of Sll on OS was analyzed using the Cox proportional hazards model.Receiver operating characteristic(ROC)curves were used to compare the predictive ability of Sll,NLR,and PLR.Results:Sll equal to or higher than 660 was significantly associated with old age,large tumor size,unfavorable Borrmann classification,advanced tumor invasion,lymph node metastasis,distant metastasis,advanced TNM stage,and high carcino-embryonic antigen level,high neutrophil-lymphocyte ratio,and high platelet-lymphocyte ratio(all P<0.05).High Sll was significantly associated with unfavorable prognosis(P<0.001) and Sll was an independent predictor for OS(P=0.015).Subgroups analysis further showed significant associations between high Sll and short OS in stage Ⅰ,Ⅱ,Ⅲ subgroups(all P<0.05).Sll was superior to NLR and PLR for predicting OS in patients with gastric cancer.Conclusion:Preoperative Sll level is an independent prognostic factor for OS in patients with gastric cancer.Kang Wang Feiyu Diao Zhijun Ye Xinhua Zhang Ertao Zhai Hui Ren Tong Li Hui Wu Yulong He Shirong Cai Jianhui Chen 2017Chinese Journal of Cancer2017,36,9:30
2Sleep and Cognitive Abnormalities in Acute Minor Thalamic Infarction显示文摘In order to characterize sleep and the cognitive patterns in patients with acute minor thalamic infarction(AMTI), we enrolled 27 patients with AMTI and 12 matched healthy individuals. Questionnaires about sleep and cognition as well as polysomnography(PSG) were performed on days 14 and 90 post-stroke. Compared to healthy controls, in patients with AMTI, hyposomnia was more prevalent; sleep architecture was disrupted as indicated by decreased sleep efficiency, increased sleep latency, and decreased non-rapid eye movement sleep stages 2 and 3;more sleep-related breathing disorders occurred; and cognitive functions were worse, especially memory. While sleep apnea and long-delay memory recovered to a large extent in the patients, other sleep and cognitive function deficit often persisted. Patients with AMTI are at an increased risk for hyposomnia, sleep structure disturbance,sleep apnea, and memory deficits. Although these abnormalities improved over time, the slow and incomplete improvement suggest that early management should be considered in these patients.Wei Wu Linyang Cui Ying Fu Qianqian Tian Lei Liu Xuan Zhang Ning Du Ying Chen Zhijun Qiu Yijun Song Fu-Dong Shi Rong Xue 2016Neuroscience Bulletin2016,32,4:28
3Identification of a Stable Quantitative Trait Locus for Percentage Grains with White Chalkiness in Rice (Oryza sativa)显示文摘High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice (Oryza sativa L.) in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness (QTLqPGWC-8) in the interval G1149-R727 on chromosome 8 using a chromosome segment substitution line (CSSL). Here, we selected the line-CSSL50 harboring the QTLqPGWC-8 allele from the CSSLs derived from a cross between Asominori (as a recurrent parent) and IR24 (as a donor parent), which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content (AAC) and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight (TGW). The BC4F2 and BC4F3 populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC-8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G-7 and 8G-9. QTLqPGWC-8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC-8 should facilitate cloning of the gene underlying this QTL and will be of value for marker-assisted selection in breeding rice varieties with better grain quality.Tao Guo Xiaolu Liu Xiangyuan Wan Jianfeng Weng Shijia Liu Xi Liu Mingjiang Chen Jingjing Li Ning Su Fuqing Wu Zhijun Cheng Xiuping Guo Cailin Lei Jiulin Wang Ling jiang Jianmin Wan 2011Journal of Integrative Plant Biology2011,53,8:25
4Exploring atmospheric free-radical chemistry in China:the self-cleansing capacity and the formation of secondary air pollution显示文摘Since 1971,it has been known that the atmospheric free radicals play a pivotal role in maintaining the oxidizing power of the troposphere.The existence of the oxidizing power is an important feature of the troposphere to remove primary air pollutants emitted from human beings as well as those from the biosphere.Nevertheless,serious secondary air-pollution incidents can take place due to fast oxidation of the primary pollutants.Elucidating the atmospheric free-radical chemistry is a demanding task in the field of atmospheric chemistry worldwide,which includes two kinds of work:first,the setup of reliable radical detection systems;second,integrated field studies that enable closure studies on the sources and sinks of targeted radicals such as OH and NO3.In this review,we try to review the Chinese efforts to explore the atmospheric free-radical chemistry in such chemical complex environments and the possible link of this fast gas-phase oxidation with the fast formation of secondary air pollution in the city-cluster areas in China.Keding Lu Song Guo Zhaofeng Tan Haichao Wang Dongjie Shang Yuhan Liu Xin Li Zhijun Wu Min Hu Yuanhang Zhang 2019National Science Review2019,6,3:26
5Recent advances in the precise control of isolated single-site catalysts by chemical methods显示文摘The search for constructing high-performance catalysts is an unfailing topic in chemical fields. Recently, we have witnessed many breakthroughs in the synthesis of single-atom catalysts(SACs) and their applications in catalytic systems. They have shown excellent activity, selectivity, stability, efficient atom utilization and can serve as an efficient bridge between homogeneous and heterogenous catalysis. Currently, most SACs are synthesized via a bottom-up strategy; however, drawbacks such as the difficulty in accessing high mass activity and controlling homogeneous coordination environments are inevitably encountered, restricting their potential use in the industrial area. In this regard, a novel top-down strategy has been recently developed to fabricate SACs to address these practical issues. The metal loading can be increased to 5% and the coordination environments can also be precisely controlled. This review highlights approaches to the chemical synthesis of SACs towards diverse chemical reactions, especially the recent advances in improving the mass activity and well-defined local structures of SACs. Also, challenges and opportunities for the SACs will be discussed in the later part.Zhijun Li Dehua Wang Yuen Wu Yadong Li 2018National Science Review2018,5,5:21
6Availability and social determinants of community health management service for patients with chronic diseases:An empirical analysis on elderly hypertensive and diabetic patients in an eastern metropolis of China显示文摘Objective:This study aimed to determine the availability of community health management services and the relevant social determinants for elderly patients with chronic diseases.Methods:All data were obtained from the 2013 random sampling household survey on an elderly population conducted by the School of Public Health of Peking University in an eastern metropolis in China.Information from the database of the above survey involving 1495 hypertensive or diabetic patients>60 years of age,as representatives of the city,were included.The study described the availability of follow-up services by community doctors among elderly hypertensive and diabetic patients during the 12 months before the survey.An ordinal multinomial logistic regression model was used to conduct the analysis on the influence of socio-economic background upon such availability.Results:Eighty-one percent of hypertensive patients and 84.7%of diabetic patients had not received any follow-up service from community doctors within 12 months prior to the survey.Among elderly hypertensive patients,those registered as non-agricultural household members,those with high and above-average income,as well as management personnel of government agencies,enterprises,and social programs have a greater chance of accepting follow-up service by community doctors because of their relatively higher socio-economic rankings.Among elderly diabetic patients,such socio-economic factors had no significant influence on the availability of the follow-up service for chronic diseases.Conclusion:The coverage of community health management services for elderly hypertensive and diabetic patients needs improvement.More effort should focus on promoting the availability of community health management services for elderly hypertensive patients,especially those with lower socio-economic status.Zhijun Wu Weiyan Jian 2015Family Medicine and Community Health2015,3,1:16
7A Novel Chloroplast-Localized Pentatricopeptide Repeat Protein Involved in Splicing Affects Chloroplast Development and Abiotic Stress Response in Rice显示文摘Pentatricopeptide 重复(PPR ) 蛋白质在更高的植物包括一个大家庭并且在 organellar RNA 新陈代谢的各种各样的方面调制 organellar 基因表示 byparticipating。在米饭,家庭包含他们的功能仍然是的 477 个成员,和 majorityof 不清楚。在这研究,我们孤立并且描绘米饭变异的、白条纹叶(wsl ) ,它在开发早的显示萎黄病有条纹或刻痕之状态。基于地图的克隆表明 WSL 编码指向叶绿体的最新识别的米饭 PPR 蛋白质。在 wsl 异种,锐气依赖者质体基因表示是显著地下面调整的,并且质体 rRNAs 和翻译 productsaccumulate 到很底层。一致地与观察, wsl 在叶绿体抄本 rpl2 拼接显示出一个强壮的缺点,在异种导致异常抄本累积和它的产品减小。wsl 显示出提高的敏感到骆驼毛的织物,咸度,和糖,并且它积累更多的 H 2 O 2 比野类型。这些结果建议减少的翻译效率可以影响异种的反应到 abioticstress.Key 词:Junjie Tan Zhenhua Tan Fuqing Wu Peike Sheng Yueqin Heng Xinhua Wang Yulong Ren Jiulin Wang Xiuping Guo Xin Zhang Zhijun Cheng Ling Jiang Xuanming Liu Haiyang Wang Jianmin Wan 2014Molecular Plant2014,7,8:15
8Chemical compositions of precipitation and scavenging of particles in Beijing显示文摘Totally 23 precipitation samples were collected in Beijing from May to November in 2003. In order to investigate the chemical composition of precipitation samples, pH, conductivity, concentrations of water-soluble ions and organic acids were analyzed. The average pH of pre-cipitations is 6.18, belonging to the neutral range; the average conductivity is 52.23 μS/cm, which indicates that precipitations in Beijing are obviously polluted; SO 24? , NO3 ? are the most abundant anions with the average concentrations of 521 and 174 μeq·L?1, respectively; the average 2SO 4? /NO3? equivalent ratio is 3.1, which decreases by about 15% compared with the result of 1994; NH+ 4 and Ca2+ are the most abundant cations with the average concentrations of 376 and 397 μeq·L?1, respectively; formic acid, acetic acid and oxalic acid are the main organic acids with the average concentrations of 4.62, 4.60 and 1.17 μeq·L?1, respectively, accounting for 2% of the overall anions. Obvious differences between concentrations before and after precipitation are also observed by SJAC (Steam Jet Aerosol Collector), which shows the removal of particles from the atmosphere by precipitation.HU Min ZHANG Jing WU Zhijun 2005Science China Chemistry2005,48,3:15
9A cyclic nucleotide-gated channel mediates cytoplasmic calcium elevation and disease resistance in rice显示文摘The transient elevation of cytoplasmic calcium is essential for pathogen-associated molecular pattern(PAMP)-triggered immunity(PTI).However,the calcium channels responsible for this process have remained unknown.Here,we show that rice CDSI(CELL DEATH and SUSCEPTIBLE to BLAST 1)encoding OsCNGC9;a cyclic nucleotide-gated channel protein,positively regulates the resistance to rice blast disease.We show that OsCNGC9 mediates PAMP-induced Ca2+influx and that this event is critical for PAMPs-triggered ROS burst and induction of PTI-related defense gene expression.We further show that a PTI related receptor-lih cytoplasmic kinase OsRLCK185 physically interacts with and phosphorylates OsCNGC9 to activate its channel activity.Our results suggest a signaling cascade linking pattern recognition to calcium channel activation,which is required for initiation of PTI and disease resistance in rice.Jiachang Wang Xi Liu An Zhang Yulong Ren Fuqing Wu Gang Wang Yang Xu Cailin Lei Shanshan Zhu Tian Pan Yongfei Wang Huan Zhang Fan Wang Yan-Qiu Tan Yupeng Wang Xin Jin Sheng Luo Chunlei Zhou Xiao Zhang Jinling Liu Shuai Wang Lingzhi Meng Yihua Wang Xi Chen Qibing Lin Xin Zhang Xiuping Guo Zhijun Cheng Jiulin Wang Yunlu Tian Shijia Liu Ling Jiang Chuanyin Wu Ertao Wang Jian-Min Zhou Yong-Fei Wang Haiyang Wang Jianmin Wan 2019Cell Research2019,29,10:13
10Glacier retreat and its effect on stream flow in the source region of the Yangtze River显示文摘在冰河上在气候变化的效果上正在种担心融化并且水文学。在这篇文章,我们在长江的来源区域使用了二自然的小规模的盆, Tuotuo 河和 Buqu 河,中国,到表演,冰河的影响融化在溪流流动上。在在 1970, 1992 和 2009 的冰河和冰体积的程度的变化用遥感图象被评估。在一样的时间间隔上的冰河表面区域的变化用 Landsat TM/ETM+ 形象通过冰河轮廓和位置的描述被估计。在 2009,冰河表面区域分别地在 Tuotuo 河和 Baqu 河盆由 1970 价值中的 20.83% 个和 34.81% 减少了。在每盆的全部的 meltwater 供应被估计是 2.56 ??WU Shanshan YAO Zhijun HUANG Heqing LIU Zhaofei CHEN Yuansheng 2013Journal of Geographical Sciences2013,23,5:13
11Original position statistic distribution analysis study of low alloy steel continuous casting billet显示文摘The homogeneity of low alloy steels continuous casting billet obtained under different technological conditions has been investigated by original position statistic distribution analysis technique. On the basis of systematic analysis of ten thousands primary optical signals at the corresponding original positions, the quantitative statistic distribution information of each element was obtained. The biggest degrees of segregation of low alloy steel continuous casting billet were calculated accurately according to the quantitative distribution maps of the contents. It was suggested that the weight ratio in a certain content range was used to judge the homogeneity of the materials, and the two models —— the total weight ratio of contents (the degree of statistic homogeneity, H) within the permissive content range (C0±R) and the median value confidence extension ratio (the degree of statistic segregation, S) at 95% of confidence limit of weight ratio —— were put forward. The two models reflect the composition and state distribution regularity of the metal materials in a large region. The difference between the sample with high columnar crystal and the sample with high equiaxed crystal has been studied by using the two models.WANG Haizhou ZHAO Pei CHEN Jiwen LI Meiling YANG Zhijun WU Chao 2005Science China(Technological Sciences)2005,48,1:13
12Spatial-temporal patterns of major ion chemistry and its controlling factors in the Manasarovar Basin, Tibet显示文摘因为它的唯一的地理环境,在南部的西藏的 Manasarovar 盆,在佛教被认为一块神圣陆地,引起了国际学术注意。在这研究,基于 43 水里的主要离子集中的实际大小,样品在年期间收集了 2005 和 2012,我们全身地在湖和 inflowing 河分析了水化学和它的控制因素的空间时间的模式。结果表明在 Manasarovar 盆的水是稍微碱的,与在 7.47.9 之间变化的 pH。分别地,在湖和河水的全部的溶解固体(TDS ) 的数量是约 325.4 和 88.7 mg/l 在西藏的高原在大多数表面水里比那降低。因为成为蒸气的结晶化的长期的效果,在湖, Na <啜class=“ a-plus-plus ”>+和 HCO <潜水艇class=“ a-plus-plus ”> 3 <啜class=“ a-plus-plus ”>有最高的集中,为全部的阳离子和阴离子内容中的46.8%个和86.8%的财务。在 inflowing 河里,然而,主导的离子是 Ca < 啜 class= “ a-plus-plus ” >2+ 和 HCO < 潜水艇 class= “ a-plus-plus ” > 3 < 啜 class= “ a-plus-plus ” > 为全部的阳离子和阴离子内容中的 59.6% 个和 75.4% 的 , 财务。水交换为如此的一个大湖是不够的,导致离子作文的一个显著空间变化。分别地湖,离子集中在湖的另外的方面上在比那显著地高的北方方面上有几条大 inflowing 河,与 468.9 和 254.9 mg/l 的 TDS。在复杂环境的影响下面,在水化学的空间变化在河里是甚至更重要的,与展出一个更高离子的内容的 upstreams。臼齿的比率在之间( Ca <啜class=“ a-plus-plus ”>2+ +Mg2+)并且( Na <啜class=“ a-plus-plus ”>+ +K+)比 1.0 高得多,表明水里的离子的主要来源是捱过的碳酸盐。尽管自然过程例如捱过的摇滚乐,是在盆控制主要离子化学的主要因素,在未来,我们需要对人为的影响给予更多的注意。YAO Zhijun WANG Rui LIU Zhaofei WU Shanshan JIANG Liguang 2015Journal of Geographical Sciences2015,25,6:11
13Spatial gradient distributions of thermal shock-induced damage to granite显示文摘In this study,we attempted to investigate the spatial gradient distributions of thermal shock-induced damage to granite with respect to associated deterioration mechanisms.First,thermal shock experiments were conducted on granite specimens by slowly preheating the specimens to high temperatures,followed by rapid cooling in tap water.Then,the spatial gradient distributions of thermal shock-induced damage were investigated by computed tomography(CT)and image analysis techniques.Finally,the influence of the preheating temperature on the spatial gradients of the damage was discussed.The results show that the thermal shock induced by rapid cooling can cause more damage to granite than that induced by slow cooling.The thermal shock induced by rapid cooling can cause spatial gradient distributions of the damage to granite.The damage near the specimen surface was at a maximum,while the damage inside the specimen was at a minimum.In addition,the preheating temperature can significantly influence the spatial gradient distributions of the thermal shock-induced damage.The spatial gradient distribution of damage increased as the preheating temperature increased and then decreased significantly over 600C.When the preheating temperature was sufficiently high(e.g.800C),the gradient can be ignored.Lifeng Fan Jingwei Gao Xiuli Du Zhijun Wu 2020Journal of Rock Mechanics and Geotechnical Engineering2020,12,5:11
14Transcriptional activation and phosphorylation of OsCNGC9 confer enhanced chilling tolerance in rice显示文摘Low temperature is a major environmental factor that limits plant growth and productivity.Although transient elevation of cytoplasmic calcium has long been recognized as a critical signal for plant cold tolerance,the calcium channels responsible for this process have remained largely elusive.Here we report that OsCNGC9,a cyclic nucleotide-gated channel,positively regulates chilling tolerance by mediating cytoplasmic calcium elevation in rice(Oryza sativa).We showed that the loss-of-function mutant of OsCNGC9 is defective in cold-induced calcium influx and more sensitive to prolonged cold treatment,whereas OsCNGC9 overexpression confers enhanced cold tolerance.Mechanistically,we demonstrated that in response to chilling stress,OsSAPK8,a homolog of Arabidopsis thaliana OST1,phosphorylates and activates OsCNGC9 to trigger Ca2+influx.Moreover,we found that the transcription of OsCNGC9 is activated by a rice dehydration-responsive element-binding transcription factor,OsDREB1A.Taken together,our results suggest that OsCNGC9 enhances chilling tolerance in rice through regulating cold-induced calcium influx and cytoplasmic calcium elevation.Jiachang Wang Yulong Ren Xi Liu Sheng Luo Xiao Zhang Xin Liu Qibing Lin Shanshan Zhu Hua Wan Yang Yang Yu Zhang Bin Lei Chunlei Zhou Tian Pan Yongfei Wang Mingming Wu Ruonan jing Yang Xu Meng Han Fuqing Wu Cailin Lei Xiuping Guo Zhijun Cheng Xiaoming Zheng Yihua Wang Zhigang Zhao Ling Jiang Xin Zhang Yong-Fei Wang Haiyang Wang Jianmin Wan 2021Molecular Plant2021,14,2:10
15Leakage performance of floating ring seal in cold/hot state for aero-engine显示文摘Rotating experimental investigations were carried out to study the oil sealing capability of two different floating ring seals in cold/hot state for aero-engine. High-speed Floating Ring Seal(HFRS) is a seal with the inner diameter of 83.72 mm and maximum speed of 38000 r/min, and Low-speed Floating Ring Seal(LFRS) is another seal with the inner diameter of 40.01 mm and maximum speed of 18000 r/min. In hot state, sealing air with the temperature of 371 K and oil with the temperature of 343 K was employed to model the working conditions of an aero-engine. Comparisons between floating ring seal and labyrinth seal were done to inspect the leakage performance.More attention was paid to the critical pressure ratio where the oil leakage began. Results show that the critical pressure ratio in cold state is obviously larger than that in hot state for both seals. An underlying sealing mechanism for floating ring seal is clarified by the fluid film, which closely associates with the dimensionless parameter of clearance over rotating diameter(2 c/Dr). Another fantastic phenomenon is that the leakage coefficient in hot state, not the leakage magnitude, is unexpectedly larger than that in cold state. Overall, the leakage performance of the floating ring seal is better than the labyrinth seal.Guoqing LI Qian ZHANG Enliang HUANG Zhijun LEI Hongwei WU Gang XU 2019Chinese Journal of Aeronautics2019,32,9:9
16An Approach of Steganography in G.729 Bitstream Based on Matrix Coding and Interleaving显示文摘This paper proposes an approach of secure communication through the Internet based on the technology of speech information hiding. In this approach,the algorithm of embedding a 2.4Kbps low-bit-rate Mixexcitation linear prediction(MELP) speech into G.729 coding speech is presented by adapting the techniques of covering code and the interleaving. The parameters in G.729 source codec are analyzed in the Capability of noise tolerance(CNT) and selected to carry secret speech data because these parameters have less impact on the quality of being reconstructed speech. Experiment results show that the proposed steganography algorithm not only gained a high data embedding rate up to 2.4Kbps but also achieved better imperceptibility, which indicates that the algorithm can be used for high data embedding capacity hiding and can achieve good effect.WU Zhijun CAO Haijuan LI Douzhe 2015Chinese Journal of Electronics2015,24,1:9
17Electroacupuncture at He-Mu points reduces P2X_4 receptor expression in visceral hypersensitivity显示文摘Electroacupuncture at Shangjuxu (ST37) and Tianshu (ST25) was reported to improve visceral hypersensitivity in rats.Colorectal distension was utilized to generate a rat model of chronic visceral hypersensitivity in irritable bowel syndrome.Results showed that abdominal withdrawal reflex scores noticeably increased after model establishment.Simultaneously,P2X 4 receptor immunoreactivity significantly increased in the colon and spinal cord.Electroacupuncture and pinaverium bromide therapy both markedly decreased abdominal withdrawal reflex scores in rats with visceral hypersensitivity,and significantly decreased P2X 4 receptor immunoreactivity in the colon and spinal cord.These data suggest that electroacupuncture treatment can improve visceral hypersensitivity in rats with irritable bowel syndrome by diminishing P2X 4 receptor immunoreactivity in the colon and spinal cord.Xinxin Guo Jifei Chen Yuan Lu Luyi Wu Zhijun Weng Ling Yang Yuhu Xin Xianming Lin Yi Liang Jianqiao Fang 2013Neural Regeneration Research2013,8,22:9
18Annual variations of black carbon over the Yangtze River Delta from 2015 to 2018显示文摘In this study,the black carbon (BC) measurements in the atmosphere of Nanjing,China were continuously conducted from 2015 to 2018 using a Model AE-33 aethalometer.By combining dataset of PM_(2.5),PM_(10),CO,NO_2,SO_2,O_3 and meteorological parameters,the temporal variations and the source apportionment of BC were given in this study.The results showed that the PM_(2.5) mass concentrations decreased in Nanjing,with an average annual rate of variation of 6.50μg/(m^3·year).Differently,the annual average concentrations of BC increased with an average annual variation rate of 214.71 ng/(m^3·year).The seasonal variations showed the pattern of BC mass concentrations in winter>autumn>spring>summer.The diurnal variations of BC mass concentrations showed a double-peak in all four seasons.The first peak occurred at approximately 7:00 in spring,summer and autumn and around 8:00 in winter.The second peak took place after 18:00.The average AAE (absorption ?ngstr?m exponent) was 1.26 with a maximum of 1.35 during wintertime and the lowest(1.12) during summertime.In addition,the AAE was smaller in the daytime than that at night,with a minimum occurring between 13:00 and 14:00.BC and visibility show a good power-function relationship at different humidity levels.The average values of the visibility thresholds of the BC mass concentrations in spring,summer,autumn and winter were 1.326,5.522,1.340 and 0.708μg/m^3,respectively.The greater the relative humidity,the smaller the visibility threshold for the BC mass concentrations was.Yue Tan Honglei Wang Shuangshuang Shi Lijuan Shen Chen Zhang Bin Zhu Song Guo zhijun Wu Ziyi Song Yan Yin Ankang Liu 2020Journal of Environmental Sciences2020,32,10:8
19Evolution of particle number size distribution in an urban atmosphere during episodes of heavy pollution and new particle formation显示文摘This study discusses the evolution of particle number size distribution during episodes of heavy pollution and new particle formation in the urban atmosphere of Beijing to quantify the effects of dynamic processes (coagulation and condensation) on the particle number size distribution.During a heavy-pollution event,an extremely low number concentration of 3-10 nm particles (on average 46 cm-3) was observed.This is because nucleation-mode particles were easily removed by strong coagulational scavenging of larger particles under this condition.In addition,a large condensation sink (on average 0.13 s-1) restrained nucleation,which is one of the major sources of nucleation-mode particles.Conversely,during a new-particle formation event,the small condensation sink (0.01 s-1) of precursor facilitated nucleation.At the same time,preexisting particles had little ability to scavenge newly formed particles (around 1 nm) and allowed them to grow to a detectable size (larger than 3 nm currently).We suggest that the effects of dynamic processes (coagulation and condensation) on particle size distribution should be stressed under some extreme conditions of the relatively polluted urban atmosphere in addition to traffic and meteorological factors.WU ZhiJun, HU Min YUE DingLi Birgit WEHNER Alfred WIEDENSOHLER 2011Science China Earth Sciences2011,54,11:8
20The scientific connotation of oil and gas formations under deep fluids and organic-inorganic interaction显示文摘As a relatively stable craton block in the earth system, the petroliferous basin is influenced by the evolution of the earth system from the early development environment of source rocks, hydrocarbon formation, and reservoir dissolution to hydrocarbon accumulation or destruction. As a link between the internal and external factors of the basin, deep fluids run through the whole process of hydrocarbon formation and accumulation through organic-inorganic interaction. The nutrients carried by deep fluids promote the bloom of hydrocarbon-generating organisms and extra addition of carbon and hydrogen source, which are beneficial to the development of high-quality source rock and enhancement of the hydrocarbon generation potential. The energy carried by the deep fluid promotes the early maturation of the source rock and facilitates the hydrocarbon generation by activation and hydrogenation in high-mature hydrocarbon sources. The dissolution alteration of carbonate rocks and clastic reservoirs by CO_2-rich deep fluids improves the deep reservoir space, thus extending the oil and gas reservoir space into greater depth. The extraction of deeply retained crude oil by deep supercritical CO_2 and the displacement of CH_4 in shale have both improved the hydrocarbon fluidity in deep and tight reservoirs. Simultaneously, the energy and material carried by deep fluids(C, H, and catalytic substances) not only induce inorganic CH_4 formation by Fischer-Tropsch(F-T) synthesis and 'hydrothermal petroleum' generation from organic matter by thermal activity but also cause the hydrothermal alteration of crude oil from organic sources. Therefore, from the perspective of the interaction of the earth's sphere, deep fluids not only input a significant amount of exogenous C and H into sedimentary basins but also improve the reservoir space for oil and gas, as well as their enrichment and accumulation efficiencies.Quanyou LIU Dongya ZHU Qingqiang MENG Jiayi LIU Xiaoqi WU Bing ZHOU Qi FU Zhijun JIN 2019Science China Earth Sciences2019,62,3:8
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