|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Millennial temperature reconstruction based on tree-ring widths of Qilian juniper from Wulan,Qinghai Province,China显示文摘The climate of the past 1000 years is an important context for evaluating the recent climate warming.However,there are few 1000-year-long climate reconstructions with annual resolution in the Qing-hai-Tibet Plateau.In this paper,a dendroclimatic analysis was conducted for the radial growth of Qilian juniper from the upper forest limit in Wulan,Qinghai Province.The results of correlation analysis between the tree-ring widths and the climate variables indicate that the growth of junipers at the upper forest limit is mainly limited by low temperatures of September,November and February of the pregrowth season,and July of the current growth season.There is no significant correlation between the tree-ring widths and precipitation.A mean temperature from the previous year's September to the current year's April was reconstructed for the Wulan area since A.D.1000.The reconstruction can explain 40.8% of the instrumental variance in the calibration period(1856―2002).The reconstruction shows that the 20th century is the warmest 100 years,and the 1990s is the warmest decade during the past 1000 years,while the coldest 100 years and decade occur at 1600―1699 and 1642―1651,respectively.The variations are verified well by the temperature reconstruction of the middle Qilian Mountain(QL) and the total organic carbon(TOC) in the Qinghai Lake sediments.The comparison of our reconstruction with the annual temperature reconstruction of extra-tropical Northern Hemisphere suggests that the climate of Wulan during the Medieval Warm Period is of obvious regional specialty,but there was a good response to the climate of hemispheric scales during the recent 400 years. | ZHU HaiFeng ZHENG YongHong SHAO XueMei LIU XiaoHong XU Yan LIANG ErYuan | 2008 | Chinese Science Bulletin2008，53，24： | 40 |
| 2 | One-step high-efficiency CRISPR/Cas9-mediated genome editing in Streptomyces显示文摘编辑技术 CRISPR 的指导 RNA 的 DNA 定期聚类 interspaced 短 palindromic repeats/Cas9 被用来介绍双 stranded 闯入染色体并且在细菌指导随后的地点特定的插入 / 删除或基因材料的代替例如 Escherichia coli,链球菌肺病,和乳杆菌 reuteri。在这研究,我们建立了在 Streptomyces 基因操作为使用编辑 plasmid pKCcas9dO 的一个高效率的 CRISPR/Cas9 染色体,它包括目标特定的指南 RNA,优化 codon 的 cas9,和二个指导相同的修理模板。由交付编辑 plasmids 进模型紧张 Streptomyces coelicolor M145 的 pKCcas9dO 系列,通过一步舞 intergeneric 转移,我们完成了与60%100%的高效率在不同层次编辑的染色体,包括单个基因删除,例如 actII-orf4 ,整顿,和 glnR ,并且单个大尺寸的基因簇删除,扮演 21.3 kb , undecylprodigiosin 红 31.6 kb ,和 Ca 2+-dependent 抗菌素例如 actinorhodin 的抗菌素 biosynthetic 簇 82.8 kb 。而且,我们也分别地与 54% 和 45% 的高效率认识到 actII-orf4 和整顿,并且 ACT 和红 biosynthetic 基因簇的同时的删除。最后,我们使用了这个系统介绍核苷酸点变化进 rpsL 基因,它与抵抗授与异种到链球菌。用这个系统,显著地,为一个轮染色体修正要求的时间被三分之一个减少或为常规方法的那些的一个一半。这些结果清楚地显示实质地编辑系统的确定的 CRISPR/Cas9 染色体改进与当前存在的方法相比编辑效率在的染色体 Streptomyces,和它在另外的放线菌种类为申请有诺言到染色体修正。 | He Huang Guosong Zheng Weihong Jiang Haifeng Hu Yinhua Lu | 2015 | Acta Biochimica et Biophysica Sinica2015，47，4： | 37 |
| 3 | China's Sponge City construction: A discussion on technical approaches显示文摘 | Haifeng Jia Zheng Wang Xiaoyue Zhen Mike Clar Shaw L. Yu | 2017 | Frontiers of Environmental Science & Engineering2017，11，4： | 15 |
| 4 | SWMM-based methodology for block-scale LID-BMPs planning based on site-scale multi-objective optimization: a case study in Tianjin显示文摘最好的管理惯例(LID-BMPs ) 的低影响发展类型试图减轻城市的 stormwater 流量并且以一个节俭、 eco 友好的方法减少污染物质负担并且在现代城市的 stormwater 管理成为了一颗全球担心。新方法论基于为块规模 LID-BMPs 计划的 stormwater 管理模型(SWMM ) 被开发。在地点规模的综合 LID-BMP 链布局优化在全部块规模与情形分析打包的这个方法城市的区域。非统治的排序的基因算法(NSGA-II ) 成功地通过大蟒被联合到 SWMM 完成地点规模优化过程。研究区域的不同的盖情形根据优化 LID-BMP 链布局被设计。认为流量是数量索引,污染物质负担,和构造费用的多索引评估同时帮助了作为计划计划的期末考试选择划算的情形。在天津的案例研究,中国,被进行表明建议方法论。结果显示出全部的流量体积, 22%-46% 山峰流动减小效率,和超过 32% 污染物质移动率的那超过 75% 控制率被完成。坚韧性分析显示选择最后的计划计划与改变的重量价值是更加柔韧的。 | Te Xu Haifeng Jia Zheng Wang Xuhui Mao Changqing Xu | 2017 | Frontiers of Environmental Science & Engineering2017，11，4： | 13 |
| 5 | Isolation and identification of stem cells from degenerated human intervertebral discs and their migration characteristics显示文摘间充质的干细胞(MSC ) 从 intervertebral 圆盘的三个部件独立被孤立并且识别,即体环 fibrosus (AF ) ,原子核 pulposus (NP ) ,和软骨终板(CEP ) 。然而,很少研究被执行了比较这些三种干细胞的性质,他们为他们的潜在的临床的应用程序必要的特别移植能力。在这研究,分别地, MSC 人的堕落磁盘从 AF, NP,和 CEP 被孤立并且在经过 3 点由表面标记和 multilineage 区别试金识别了。干细胞的这三种类型作为 AF-MSCs, NP-MSCs,和 CEP-MSCs 被说出。然后,他们的生物特征以增长,经过,殖民地形成,移植,和侵略能力被比较。结果证明房间的所有三种类型作为 MSC 被识别并且在增长,经过,和殖民地形成能力有类似的特征。当 NP-MSCs 显示出最低迁居能力时, CEP-MSCs 显示出最高的迁居和侵略力量,建议那 CEP-MSCs 并且几乎,没有侵略力量有移植和侵略的最强大的性质什么时候与 AF-MSCs 和 NP-MSCs 相比。比的, CXCR4 的表示才在 CEP-MSCs 是更高的在。 | Shuhao Liu Haifeng Liang Soo-min Lee Zheng Li Jian Zhang Qinming Fei | 2017 | Acta Biochimica et Biophysica Sinica2017，49，2： | 10 |
| 6 | Effects of Forest Type and Urbanization on Carbon Storage of Urban Forests in Changchun, Northeast China显示文摘Rapid urbanization has led to dramatic changes in urban forest structures and functions, and consequently affects carbon(C) storage in cities. In this study, field surveys were combined with high resolution images to investigate the variability of C storage of urban forests in Changchun, Northeast China. The main objectives of this study were to quantify the C storage of urban forests in Changchun City, Northeast China and understand the effects of forest type and urbanization on C storage of urban forests. The results showed that the mean C density and the total C storage of urban forests in Changchun were 4.41 kg/m2 and 4.74 × 108 kg, respectively. There were significant differences in C density among urban forest types. Landscape and relaxation forest(LF) had the highest C density with 5.41 kg/m2, while production and management forest(PF) had the lowest C density with 1.46 kg/m2. These differences demonstrate that urban forest type is an important factor needed to be considered when the C storage is accurately estimated. Further findings revealed significant differences in different gradients of urbanization, and the mean C density decreased from the first ring(6.99 kg/m2) to the fourth ring(2.87 kg/m2). The total C storage increased from the first ring to the third ring. These results indicate that C storage by urban forests will be significantly changed during the process of urbanization. The results can provide insights for decision-makers and urban planners to better understand the effects of forest type and urbanization on C storage of urban forests in Changchun, and make better management plans for urban forests. | ZHANG Dan ZHENG Haifeng REN Zhibin ZHAI Chang SHEN Guoqiang MAO Zhixia WANG Peijiang HE Xingyuan | 2015 | Chinese Geographical Science2015，25，2： | 9 |
| 7 | Effectiveness of Inactivated COVID-19 Vaccines Against Symptomatic,Pneumonia,and Severe Disease Caused by the Delta Variant:Real World Study and Evidence—China,2021显示文摘Summary What is already known about this topic?Effectiveness of China’s 2 inactivated vaccines(BBIBPCorV and CoronaVac)against pre-Delta severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)variants ranged from 47%to over 90%,depending on the clinical endpoint,and with greater effectiveness against more severe coronavirus disease 2019(COVID-19).During an outbreak in Guangdong,inactivated vaccine effectiveness(VE)against the Delta variant was 70%for symptomatic infection and 100%for severe COVID-19.However,separate or combined VE estimates for the two inactivated vaccines against Delta are not available.What is added by this report?In an outbreak that started in a hospital,VEs of completed primary vaccination with inactivated COVID-19 vaccines against symptomatic COVID-19,COVID-19 pneumonia,and severe COVID-19 caused by the Delta variant were 51%,61%,and 82%.Completed primary vaccination reduced the risk of progressing from mild to moderate or severe COVID-19 by 74%.VE estimates for BBIBP-CorV and CoronaVac or combined vaccination were similar,and partial vaccination was ineffective.What are the implications for public health practice?Completed primary vaccination with either of the 2 inactivated COVID-19 vaccines reduces risk of symptomatic COVID-19,COVID-19 pneumonia,and severe COVID-19 caused by the Delta variant.Completion of the completed primary vaccination with two doses is necessary for protection from Delta. | Dan Wu Yanyang Zhang Lin Tang Fuzhen Wang Ying Ye Chao Ma Hui Zheng Wenzhou Yu Lei Cao Yifan Song Abuduwaili Reyimu Xiaoxiao Zhang Haifeng Wang Yifei Nie Mingxia Lu Muge Qi Jun Li Ruolin Wang Kaichao Yang Changshuang Wang Lawrence Everett Rodewald Geroge Fu Gao Zhijie An Zundong Yin | 2022 | China CDC weekly2022，4，4： | 7 |
| 8 | Effects of Urbanization,Soil Property and Vegetation Configuration on Soil Infiltration of Urban Forest in Changchun,Northeast China显示文摘Urban forest soil infiltration, affected by various factors, is closely related with surface runoff. This paper studied the effect of urban forest types, vegetation configuration and soil properties on soil infiltration. In our study, 191 typical plots were sampled in Changchun City, China to investigate the soil infiltration characteristics of urban forest and its influencing factors. Our results showed that the steady infiltration rates of urban forest soil were highly variable. High variations in the final infiltration rates were observed for different vegetation patterns and compaction degrees. Trees with shrubs and grasses had the highest infiltration rate and trees with bare land had the lowest infiltration rate. In addition, our results showed that the soil infiltration rate decreased with an increase in the bulk density and with a reduction in the soil organic matter content and non-capillary porosity. The soil infiltration rate also had significantly positive relationships with the total porosity and saturated soil water content. Urban soil compaction contributed to low soil infiltration rates. To increase the infiltration rate and water storage volume of urban forest soil, proper techniques to minimize and mitigate soil compaction should be used. These findings can provide useful information for urban planners about how to maximize the water volume of urban forest soil and decrease urban instantaneous flooding. | WANG Peijiang ZHENG Haifeng REN Zhibin ZHANG Dan ZHAI Chang MAO Zhixia TANG Ze HE Xingyuan | 2018 | Chinese Geographical Science2018，28，3： | 7 |
| 9 | The mutational pattern of homologous recombination(HR)-associated genes and its relevance to the immunotherapeutic response in gastric cancer显示文摘Objective:Currently,there is an urgent need to identify immunotherapeutic biomarkers to increase the benefit of immune checkpoint inhibitors(ICIs)for patients with gastric cancer(GC).Homologous recombination deficiency(HRD)can modify the tumor immune microenvironment by increasing the presence of tumor-infiltrating lymphocytes and therefore might serve as a biomarker of immunotherapeutic response.We aimed to analyze the mutational pattern of HR-associated genes in Chinese patients with GC and its relevance to the tumor immune profile and clinical immunotherapeutic response.Methods:A panel of 543 cancer-associated genes was used to analyze genomic profiles in a cohort comprising 484 Chinese patients with GC.Correlations between HR gene mutations and tumor immunity or clinical outcomes were identified via bioinformatic analysis using 2 GC genomic datasets(TCGA and MSK-IMPACT).Results:Fifty-one of the 484(10.54%)patients carried at least one somatic mutation in an HR gene;ATM(16/484,3.31%)was among the most frequently mutated HR genes in the Chinese cohort.Mutations in HR genes were associated with elevated tumor mutational burden,enhanced immune activity,and microsatellite instability status.In the MSK-IMPACT cohort comprising 49 patients with stomach adenocarcinoma or gastroesophageal junction adenocarcinoma treated with ICIs,patients with HR-mut GC(n=12)had significantly better overall survival than those with HR-wt GC(n=37)(log-rank test,P<0.05).Conclusions:Our data suggest that detection of somatic mutations in HR genes might aid in identifying patients who might benefit from immune checkpoint blockade therapy. | Yue Fan Haifeng Ying Xueying Wu Huan Chen Ying Hu Henghui Zhang Lijia Wu Ying Yang Beibei Mao Lan Zheng | 2020 | Cancer Biology & Medicine2020，17，4： | 6 |
| 10 | Structural shifts in the intestinal microbiota of rats treated with cyclosporine A after orthotropic liver transplantation显示文摘Understanding the effect of immunosuppressive agents on intestinal microbiota is important to reduce the mortality and morbidity from orthotopic liver transplantation (OLT). We investigated the relationship between the commonly used immunosuppressive agent cyclosporine A (CSA) and the intestinal microbial variation in an OLT model. The rat samples were divided as follows:(1) N group (normal control);(2) I group (isograft LT, Brown Norway [BN] rat to BN);(3) R group (allograft LT, Lewis to BN rat);and (4) CSA group (R group treated with CSA). The intestinal microbiota was assayed by denaturing gradient gel electrophoresis profiles and by using real-time polymerase chain reaction. The liver histopathology and the alanine/aspartate aminotransferase ratio after LT were both ameliorated by CSA. In the CSA group, the numbers of rDNA gene copies of Clostridium cluster I, Clostridium cluster XIV, and Enterobacteriaceae decreased, whereas those of Faecalibacterium prausnitzii increased compared with the R group. Cluster analysis indicated that the samples from the N, I, and CSA groups were clustered, whereas the other clusters contained the samples from the R group. Hence, CSA ameliorates hepatic graft injury and partially restores gut microbiota following LT, and these may benefit hepatic graft rejection. | Junjun Jia Xinyao Tian Jianwen Jiang Zhigang Ren Haifeng Lu Ning He Haiyang Xie Lin Zhou Shusen Zheng | 2019 | Frontiers of Medicine2019，13，4： | 5 |
| 11 | Void fraction measurement of bubble and slug flow in a small channel using the multivision technique显示文摘 | Huajun Li Xiaohu Zheng Haifeng Ji Zhiyao Huang Baoliang Wang Haiqing Li | 2017 | Particuology2017，15，4： | 5 |
| 12 | Topographical changes of ground surface affected by the shelterbelt along the Tarim Desert Highway显示文摘To study the effects of sand protection project on modern aeolian landform, the types, distribution, and intensity of topographical changes of the ground surface affected by the shelterbelt along the Tarim Desert Highway were determined by measuring the deflation and deposition of sand surface in the Tazhong area located in the hinterland of the Taklimakan Desert. The results showed that (1) the newly-formed landform in sand protection systems is dominated by aeolian deposition including the small-scale Nabkha Dunes, the medium-scale sheet-like sand deposition and the large-scale ridge-like sand deposition. To some degree, aeolian deflation landform can also be formed in the open space in the shelterbelt. Furthermore, it is difficult for aeolian deflation landform to develop in a large scale in the interdunes. However, aeolian deflation landform can be developed in a large-scale on the windward slope of secondary dunes in longitudinal complex sand ridges; (2) on the windward side of the sand protection systems, both the morphology and strike of dwarf mobile dunes in the interdunes are changed by the sand-obstructing forest belts and the ridge-like sand deposition around it. The wind- ward slope of the ridge-like deposition around the sand-obstructing forest belt forms a stable ground surface. After being damaged by forward-moving dunes in a short period, the ground surface is re- covered gradually; (3) on the leeward side of the sand protection systems, aeolian deflations are formed widely. Particularly, the deflation depression is formed in the interdunes. In addition, the dunes in the region with highly topographic relief are cut flat by aeolian deflations; thereafter its relief of to- pography is reduced. The above analysis indicates that shelterbelts have obvious effects on the windward wind-sand flux in terms of dissipating energy and intercepting sand. With the recovery of wind velocity on the leeward side of the sand protection systems, the wind-sand flux gradually tends to be unsaturated; therefore the sand surface deflation is formed. | LI ShengYu LEI JiaQiang XU XinWen WANG HaiFeng FAN JingLong GU Feng QIU YongZhi XU Bo GONG Qing ZHENG Wei | 2008 | Chinese Science Bulletin2008，53，S2： | 4 |
| 13 | Spatiotemporal pattern of urban forest leaf area index in response to rapid urbanization and urban greening显示文摘Rapid urbanization and urban greening have caused great changes to urban forests in China. Understanding spatiotemporal patterns of urban forest leaf area index(LAI) under rapid urbanization and urban greening is important for urban forest planning and management. We evaluated the potential for estimating urban forest LAI spatiotemporally by using Landsat TM imagery. We collected three scenes of Landsat TM(thematic mapper)images acquired in 1997, 2004 and 2010 and conducted a field survey to collect urban forest LAI. Finally, spatiotemporal maps of the urban forest LAI were created using a NDVI-based urban forest LAI predictive model.Our results show that normalized differential vegetation index(NDVI) could be used as a predictor for urban forest LAI similar to natural forests. Both rapid urbanization and urban greening contribute to the changing process of urban forest LAI. The urban forest has changed considerably from 1997 to 2010. Urban vegetated pixels decreased gradually from 1997 to 2010 due to intensive urbanization.Leaf area for the study area was 216.4, 145.2 and173.7 km^2 in the years 1997, 2004 and 2010, respectively.Urban forest LAI decreased sharply from 1997 to 2004 and increased slightly from 2004 to 2010 because of numerous greening policies. The urban forest LAI class distributions were skewed toward low values in 1997 and 2004. Moreover, the LAI presented a decreasing trend from suburban to downtown areas. We demonstrate the usefulness of TM remote-sensing in understanding spatiotemporal changing patterns of urban forest LAI under rapid urbanization and urban greening. | Zhibin Ren Yunxia Du Xingyuan He Ruiliang Pu Haifeng Zheng Haide Hu | 2018 | Journal of Forestry Research2018，29，3： | 4 |
| 14 | Deformation Behavior of the Zr_(53.5)Cu_(26.5)Ni_5Al_(12)Ag_3 Bulk Metallic Glass Over a Wide Range of Strain Rate and Temperatures显示文摘The stress–strain relations for the Zr53.5Cu26.5Ni5Al12Ag3 bulk metallic glass(BMG) over a broad range of temperatures(room temperature to its supercooled liquid region) and strain rates(10-4to 10-1s-1) were established in uniaxial compression using a thermal-mechanical simulation system. The superplastic flow was seen above its glass transition temperature(Tg = 694 K) and strain rates of up to 10-1s-1from the variation of stress–strain curves. A deformation map of strain rate vs temperature of Zr53.5Cu26.5Ni5Al12Ag3 was obtained, which was mainly composed of homogeneous and inhomogeneous deformation regions,the former featuring either Newtonian or non-Newtonian flow while the latter characterizing linear elastic behavior followed by shear localization, respectively. A phenomenological constitutive equation used to describe a master curve of viscosity with respect to the strain rate was obtained by fitting the experimental results, which determines the viscosity of the present alloy at the temperature near and above Tg. The results show the Zr53.5Cu26.5Ni5Al12Ag3 BMG is the subject suitable for net shape forming process at the supercooled liquid region. | Guangcai Ma Zhengwang Zhu Zheng Wang Haifeng Zhang | 2015 | Journal of Materials Science & Technology2015，31，9： | 4 |
| 15 | Three dysregulated microRNAs in serum as novel biomarkers for gastric cancer screening显示文摘 | Hui Wang Lei Wang Zheng Wu Rong Sun Haifeng Jin Jifeng Ma Lili Liu Rui Ling Jun Yi Ling Wang Jiefang Bian Jianghao Chen Nanlin Li Shifang Yuan Jun Yun | 2014 | Medical Oncology2014，，12： | 4 |
| 16 | Creation of aromatic maize by CRISPR/Cas显示文摘Aroma is an important quality parameter for breeding in rice(Oryza sativa).For example,the aromatic rice varieties basmati and jasmine rice,with a popcorn-like scent,are popular worldwide and routinely command a price premium.2-acetyl-1-pyrroline(2AP)is a key flavor compound among over 200 volatiles identified in fragrant rice.A naturally fragrant germplasm exists in multiple plant species besides rice,which all exhibit lower activity of BETAINE ALDEHYDE DEHYDROGENASE 2(BADH2).However,no equivalent aromatic germplasm has been described in maize(Zea mays).Here,we characterized the two maize BADH2 homologs,ZmBADH2a and ZmBADH2b.We generated zmbadh2a and zmbadh2b single mutants and the zmbadh2a-zmbadh2b double mutant by CRISPR/Cas in four inbred lines.A popcorn-like scent was only noticeable in seeds from the double mutant,but not from either single mutant or in wild type.In agreement,we only detected 2AP in fresh kernels and dried mature seeds from the double mutant,which accumulated between 0.028 and 0.723 mg/kg 2AP.These results suggest that ZmBADH2a and ZmBADH2b redundantly participate in 2AP biosynthesis in maize,and represent the creation of the world's first aromatic maize by simultaneous genome editing of the two BADH2 genes. | Yanxiao Wang Xiaoqin Liu Xiuxiu Zheng Wenxia Wang Xunqing Yin Haifeng Liu Changle Ma Xiaomu Niu Jian-Kang Zhu Fei Wang | 2021 | Journal of Integrative Plant Biology2021，63，9： | 3 |
| 17 | In vivo degradation and endothelialization of an iron bioresorbable scaffold显示文摘Detection of in vivo biodegradation is critical for development of next-generation medical devices such as bioresorbable stents or scaffolds(BRSs).In particular,it is urgent to establish a nondestructive approach to examine in vivo degradation of a new-generation coronary stent for interventional treatment based on mammal experiments;otherwise it is not available to semi-quantitatively monitor biodegradation in any clinical trial.Herein,we put forward a semi-quantitative approach to measure degradation of a sirolimus-eluting iron bioresorbable scaffold(IBS)based on optical coherence tomography(OCT)images;this approach was confirmed to be consistent with the present weight-loss measurements,which is,however,a destructive approach.The IBS was fabricated by a metal-polymer composite technique with a polylactide coating on an iron stent.The efficacy as a coronary stent of this new bioresorbable scaffold was compared with that of a permanent metal stent with the name of trade mark Xience,which has been widely used in clinic.The endothelial coverage on IBS was found to be greater than on Xience after implantation in a rabbit model;and our well-designed ultrathin stent exhibited less individual variation.We further examined degradation of the IBSs in both minipig coronary artery and rabbit abdominal aorta models.The present result indicated much faster iron degradation of IBS in the rabbit model than in the porcine model.The semi-quantitative approach to detect biodegradation of IBS and the finding of the species difference might be stimulating for fundamental investigation of biodegradable implants and clinical translation of the next-generation coronary stents. | Wenjiao Lin Hongjie Zhang Wanqian Zhang Haiping Qi Gui Zhang Jie Qian Xin Li Li Qin Haifeng Li Xiang Wang Hong Qiu Xiaoli Shi Wei Zheng Deyuan Zhang Runlin Gao Jiandong Ding | 2021 | Bioactive Materials2021，6，4： | 3 |
| 18 | Thiol-stabilized atomically precise, superatomic silver nanoparticles for catalysing cycloisomerization of alkynyl amines显示文摘Both the electronic and surface structures of metal nanomaterials play critical roles in determining their chemical properties. However, the non-molecular nature of conventional nanoparticles makes it extremely challenging to understand the molecular mechanism behind many of their unique electronic and surface properties. In this work, we report the synthesis, molecular and electronic structures of an atomically precise nanoparticle, [Ag206 L72]~q(L = thiolate, halide; q = charge). With a four-shell Ag7@Ag32@Ag77@Ag90 Ino-decahedral structure having a nearly perfect D_(5h) symmetry, the metal core of the nanoparticle is co-stabilized by 68 thiolate and 4 halide ligands. Both electrochemistry and plasmonic absorption reveal the metallic nature of the nanoparticles, which is explained by density functional theory calculations.Electronically, the nanoparticle can be considered as a superatom, just short of a major electron shell closing of 138 electrons(q = –4). More importantly, many of ligands capping on the nanoparticle are labile due to their low-coordination modes, leading to high surface reactivity for catalysing the synthesis of indoles from 2-ethynylaniline derivatives. The results exemplify the power of the atomic-precision nanocluster approach to catalysis in probing reaction mechanisms and in revealing the interplay of heterogeneous reactivities,electronic and surface structural dynamics, thereby providing ways for optimization. | Juanzhu Yan Jun Zhang Xumao Chen Sami Malola Bo Zhou Elli Selenius Xiaomin Zhang Peng Yuan Guocheng Deng Kunlong Liu Haifeng Su Boon K.Teo Hannu Hakkinen Lansun Zheng Nanfeng Zheng | 2018 | National Science Review2018，5，5： | 3 |
| 19 | In-situ Synthesis and Characterization of Poly(vinyl alcohol)/Hydroxyapatite Composite Hydrogel by Freezing-thawing Method显示文摘Poly(vinyl alcohol)/hydroxyapatite(PVA/HA) composite hydrogel was successfully in-situ synthesized via three cycles of freezing-thawing. The composition and structure of products were investigated by X-ray diffraction( XRD), Fourier transformed infrared spectroscopy(FTIR) and scanning electron microscopy(SEM). The influence of different preparation methods and contents of material on the mechanical properties of PVA/HA composite hydrogel was discussed through tensile and compressive tests. The template of PVA could avoid the agglomeration of HA particles, which improves the mechanical properties of the composite hydrogel effectively. The tensile strength, modulus and compressive performances of the PVA/HA composite hydrogel prepared by the in-situ synthesis method were better than those of hydrogel obtained by the simple blend metliod. In addition, the effect of the content of PVA, HA, and the pH value on tlie properties of tlie PVA/HA composite hydrogel has been discussed in detail. | MENG Deyue ZHOU Xiuqing ZHENG Keyan MIAO Chong SHENG Ye ZOU Haifeng | 2019 | Chemical Research in Chinese Universities2019，35，3： | 3 |
| 20 | Progress and prospects of horizontal well fracturing technology for shale oil and gas reservoirs显示文摘By systematically summarizing horizontal well fracturing technology abroad for shale oil and gas reservoirs since the “13th Five-Year Plan”, this article elaborates new horizontal well fracturing features in 3D development of stacked shale reservoirs, small well spacing and dense well pattern, horizontal well re-fracturing, fracturing parameters optimization and cost control. In light of requirements on horizontal well fracturing technology in China, we have summarized the technological progress in simulation of multi-fracture propagation, horizontal well frac-design, electric-drive fracturing equipment, soluble tools and low-cost downhole materials and factory-like operation. On this basis, combined with the demand analysis of horizontal well fracturing technology in the “14th Five-Year Plan” for unconventional shale oil and gas, we suggest strengthening the research and development in the following 7 aspects:(1) geology-engineering integration;(2) basic theory and design optimization of fracturing for shale oil and gas reservoirs;(3) development of high-power electric-drive fracturing equipment;(4) fracturing tool and supporting equipment for long horizontal section;(5) horizontal well flexible-sidetracking drilling technology for tapping remaining oil;(6) post-frac workover technology for long horizontal well;(7) intelligent fracturing technology. | LEI Qun XU Yun CAI Bo GUAN Baoshan WANG Xin BI Guoqiang LI Hui LI Shuai DING Bin FU Haifeng TONG Zheng LI Tao ZHANG Haoyu | 2022 | Petroleum Exploration and Development2022，49，1： | 3 |
您所在的机构暂未开通此部分的功能，请联系管理员