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1RECTANGLE: a bit-slice lightweight block cipher suitable for multiple platforms显示文摘In this paper, we propose a new lightweight block cipher named RECTANGLE. The main idea of the design of RECTANGLE is to allow lightweight and fast implementations using bit-slice techniques. RECTANGLE uses an SP-network. The substitution layer consists of 16 4 × 4 S-boxes in parallel. The permutation layer is composed of 3 rotations. As shown in this paper, RECTANGLE offers great performance in both hardware and software environment, which provides enough flexibility for different application scenario. The following are3 main advantages of RECTANGLE. First, RECTANGLE is extremely hardware-friendly. For the 80-bit key version, a one-cycle-per-round parallel implementation only needs 1600 gates for a throughput of 246 Kbits/s at100 k Hz clock and an energy efficiency of 3.0 p J/bit. Second, RECTANGLE achieves a very competitive software speed among the existing lightweight block ciphers due to its bit-slice style. Using 128-bit SSE instructions,a bit-slice implementation of RECTANGLE reaches an average encryption speed of about 3.9 cycles/byte for messages around 3000 bytes. Last but not least, we propose new design criteria for the RECTANGLE S-box.Due to our careful selection of the S-box and the asymmetric design of the permutation layer, RECTANGLE achieves a very good security-performance tradeoff. Our extensive and deep security analysis shows that the highest number of rounds that we can attack, is 18(out of 25).ZHANG WenTao BAO ZhenZhen LIN DongDai Vincent RIJMEN YANG Bo Han Ingrid VERBAUWHEDE 2015Science China Chemistry2015,58,12:22
2Self-monitoring of blood glucose in type 2 diabetic patients in China:current status and influential factors显示文摘Yuan Li Guo Xiaohui Xiong Zhenzhen Lou Qingqing Shen Li Zhao Fang Sun Zilin Li Jianwei 2014Chinese Medical Journal2014,,2:21
3Macrophagic CD146 promotes foam cell formation and retention during atherosclerosis显示文摘Yongting Luo Hongxia Duan Yining Qian Liqun Feng Zhenzhen Wu Fei Wang Jing Feng Dongling Yang Zhihai Qin Xiyun Yan 2017Cell Research2017,27,3:18
4Characteristics and origin of abnormally high porosity zones in buried Paleogene clastic reservoirs in the Shengtuo area, Dongying Sag, East China显示文摘There are three abnormally high porosity zones developed in buried Paleogene nearshore subaqueous fan and sublacustrine fan clastic reservoirs at 2,800-3,200 m, 3,250-3,700 m and 3,900-4,400 m, respectively, within the Shengtuo area of the Dongying Sag. Here the porosity of reservoirs buried deeper than 4,000 m can still be greater than 20%. Investigation of these three abnormally high porosity(AHP) zones in the 3rd to 4th member of the Paleogene Shahejie Formation in the Shengtuo area was carried out with utilization of core observation, thin section identification, SEM observation, image analysis, core physical property testing and other technical methods. The results show that, the AHP zones in 2,800-3,200 m and 3,250-3,700 m are visible pores primary AHP zones dominated by significant primary intergranular pores(more than 50% of the total porosity), while secondary pores and micropores in authigenic clays may develop in some reservoirs. AHP reservoirs in the AHP zone of 3,900-4,400 m are dominated by micropores in matrix, visible pores are mainly grain dissolution pores but with low absolute content(< 1%), so this zone belongs to the micropores primary AHP zone. The genesis of the three AHP zones was studied to distinguish between porosity enhancement and porosity preservation. Our research shows that, in deeply buried clastic reservoirs in the Shengtuo area, mineral dissolution occurred in a relatively closed diagenetic system with high temperature and high salinity. Reservoir rocks underwent extensive feldspar dissolution, while detrital carbonate grains and carbonate cements show no evidence of extensive dissolution. Although significant feldspar dissolution pores developed, feldspar dissolution enhanced porosity only a little due to the precipitation of almost isovolumetric dissolution products in the nearby primary intergranular pores in forms of authigenic clays and quartz cements. Net enhanced porosity originating from feldspar dissolution is generally less than 0.25%. Thus, the subsurface dissolution has little impact on the mid-deep buried high porosity reservoirs. Reservoirs in braided channels of middle fans in sublacustrine fans and reservoirs in the middle-front of fan bodies of nearshore subaqueous fans provide the basis for the development of AHP zones. The shallow development of fluid overpressure and early hydrocarbon emplacement have effectively retarded compaction and carbonate cementation, so that the high porosity in the superficial layers is preserved in the mid-deep layers. These are the main controlling factors in the development of AHP zones.Cao Yingchang Yuan Guanghui Li Xiaoyan Wang Yanzhong Xi Kelai Wang Xiaoming Jia Zhenzhen Yang Tian 2014Petroleum Science2014,11,3:18
5Modulating macrophage activities to promote endogenous bone regeneration: Biological mechanisms and engineering approaches显示文摘A coordinated interaction between osteogenesis and osteoimmune microenvironment is essential for successful bone healing.In particular,macrophages play a central regulatory role in all stages of bone repair.Depending on the signals they sense,these highly plastic cells can mediate the host immune response against the exterior signals of molecular stimuli and implanted scaffolds,to exert regenerative potency to a varying extent.In this article,we first encapsulate the immunomodulatory functions of macrophages during bone regeneration into three aspects,as sweeper,mediator and instructor.We introduce the phagocytic role of macrophages in different bone healing periods(‘sweeper’)and overview a variety of paracrine cytokines released by macrophages either mediating cell mobilisation,vascularisation and matrix remodelling(‘mediator’),or directly driving the osteogenic differentiation of bone progenitors and bone repair(‘instructor’).Then,we systematically classify and discuss the emerging engineering strategies to recruit,activate and modulate the phenotype transition of macrophages,to exploit the power of endogenous macrophages to enhance the performance of engineered bone tissue.Yiming Niu Zhenzhen Wang Yuchen Shi Lei Dong Chunming Wang 2021Bioactive Materials2021,6,1:14
6Palaeogeomorphology and its control on the development of sequence stratigraphy and depositional systems of the Early Silurian in the Tarim Basin显示文摘The Silurian in the Tarim Basin was deposited on the basement deformed by the Caledonian tectonic movements at the end of the Late Ordovician. The development and distribution of sedimentary sequences of the Early Silurian have been clearly controlled by the palaeogeomorphology of the Late Ordovician. Based on unconformity characteristics and distribution of erosion, several zones can be differentiated including a high uplifted erosion zone, a transitional slope zone and a depression zone. The central and west Tabei Uplift zones show high angular unconformity and intense erosion. The Tarim Basin in the late Ordovician shows characteristics of higher in the west, lower in the east while higher in the south, lower in the north. The Early Silurian mainly developed transgressive and highstand systems tracts on the whole, while the lowstand systems tract only developed partly below the slope break. The palaeogeomorphology controlled the clastic source supply and deposit distribution. Braided delta system and tidal flat–estuary system were deposited. The duration of uplifting of the Tazhong paleouplift was longer than that of the Tabei paleo-uplift, and deposition was later. This led to the lower and middle members of the Kepingtage Formation missing in that area. As a large-scale transgression occurred during the deposition period of the upper member of the Kepingtage Formation, sediment from the west of the basin was transported and deposited by tides and waves, forming tidal–marine debris systems above the uplift. Proximal alluvial fan and fan delta coarse clastic deposits developed in proximal uplift zone in the east and southeast of the basin, and braided delta put forward to the transitional zone between the edge of uplift and the sea. Large-scale tidal channel, sub-distributary channel and mouth bar of the delta front can form favorable reservoirs, and they are primary targets for oil and gas exploration. This research on sequence–depositional systems development and distribution controlled by palaeogeomorphology is significant in guiding the prediction of reservoir sandstones.Liu Jingyan Lin Changsong Cai Zhenzhong Zhu Yongfeng Yang Yongheng Peng Li Si Baoling Huang Zhen Li Huanpu Xu Yingcai Su Zhenzhen 2010Petroleum Science2010,7,3:13
7Piglets cloned from induced pluripotent stem cells显示文摘Nana Fan Jijun Chen Zhouchun Shang Hongwei Dou Guangzhen Ji Qingjian Zou Lu Wu Lixiazi He Fang Wang Kai Liu Na Liu Jianyong Han Qi Zhou Dengke Pan Dongshan Yang Bentian Zhao Zhen Ouyang Zhaoming Liu Yu Zhao Lin Lin Chongming Zhong Quanlei Wang Shouqi Wang Ying Xu Jing Luan Yu Liang Zhenzhen Yang Jing Li Chunxia Lu Gabor Vajta Ziyi Li Hongsheng Ouyang Huayan Wang Yong Wang Yang Yang Zhonghua Liu Hong Wei Zhidong Luan Miguel A Esteban Hongkui Deng Huanming Yang Duanqing Pei Ning Li Gang Pei Lin Liu Yutao Du Lei Xiao Liangxue Lai 2013Cell Research2013,23,1:12
8Chemical Compositions and Distribution Characteristics of Cements in Longmaxi Formation Shales, Southwest China显示文摘Shale gas resources have been regarded as a viable energy source, and it is of great significance to characterize the shale composition of different cements, such as quartz and dolomite. In this research, chemical analysis and the multifractal method have been used to study the mineral compositions and petrophysical structures of cements in shale samples from the Longmaxi Formation, China. X-ray diffraction, electron microprobe, field emission scanning electron microscopy, cathodoluminescence microscopy and C-O isotope analyses confirmed that cements in the Longmaxi Formation shales are mainly composed of Fe-bearing dolomite and quartz. Fe-bearing dolomite cements concentrate around dolomite as annuli, filling micron-sized inorganic primary pores. Quartz cements in the form of nanoparicles fill primary inter-crystalline pores among clay minerals. Theoretical calculation shows that the Fe-bearing dolomite cements formed slightly earlier than the quartz cements, but both were related to diagenetic illitization of smectite. Moreover, multifractal analysis reveals that the quartz cements are more irregularly distributed in pores than the Fe-bearing dolomite cements. These results suggest that the plugging effect of the quartz cements on the primary inoraganic pore structures is the dominant factor resulting in low interconnected porosity of shales, which are unfavorable for the enrichment of shale gas.Wenda Zhou Shuyun Xie Zhengyu Bao Emmanuel John M. Carranza Lei Lei Zhenzhen Ma 2019Journal of Earth Science2019,30,5:12
9Dynamic membrane bioreactor performance enhancement by powdered activated carbon addition:Evaluation of sludge morphological,aggregative and microbial properties显示文摘The effects of powdered activated carbon(PAC) addition on sludge morphological, aggregative and microbial properties in a dynamic membrane bioreactor(DMBR) were investigated to explore the enhancement mechanism of pollutants removal and filtration performance. Sludge properties were analyzed through various analytical measurements. The results showed that the improved sludge aggregation ability and the evolution of microbial communities affected sludge morphology in PAC-DMBR, as evidenced by the formation of large, regularly shaped and strengthened sludge flocs. The modifications of sludge characteristics promoted the formation process and filtration flux of the dynamic membrane(DM) layer. Additionally, PAC addition did not exert very significant influence on the propagation of eukaryotes(protists and metazoans)and microbial metabolic activity. High-throughput pyrosequencing results indicated that adding PAC improved the bacterial diversity in activated sludge, as PAC addition brought about additional microenvironment in the form of biological PAC(BPAC), which promoted the enrichment of Acinetobacter(13.9%), Comamonas(2.9%), Flavobacterium(0.31%) and Pseudomonas(0.62%), all contributing to sludge flocs formation and several(such as Acinetobacter) capable of biodegrading relatively complex organics. Therefore, PAC addition could favorably modify sludge properties from various aspects and thus enhance the DMBR performance.Zhenzhen Yu Yisong Hu Mawuli Dzakpasu Xiaochang C.Wang Huu Hao Ngo 2019Journal of Environmental Sciences2019,31,1:9
10Grhl3 induces human epithelial tumor cell migration and invasion via downregulation of E-cadherin显示文摘Grainyhead 基因涉及愈合弯屈和发展神经试管闭合。转移在细胞从主要肿瘤的地点传播哪个癌症并且在远器官建立第二等的肿瘤期间是一个 multistep 过程。粘附蛋白质 E-cadherin 在转移起一个必要作用。考虑到在在皮或乳癌发生在侵略的获得期间的愈合创伤的过程和 EMT 发生的 epithelialmesenchymal 转变(EMT ) 的类似的高度,我们在癌症侵略调查了 Grainyhead 基因的角色。这里,我们证明在象 Grainyhead 一样之间有一种反的关系 3 (Grhl3 ) 并且在某上皮的肿瘤房间的 E-cadherin 表示排队。在 E-cadherin-positive 上皮的肿瘤房间线的 Grhl3 的 Overexpression,由更少的侵略描绘了,产生了 E-cadherin 基因的 transcriptional 阻塞并且支持了房间移植和房间侵略。相反地, Grhl3 弄空禁止了房间移植和房间侵略并且与 E-cadherin 表示的获得被联系。为了推进,探索 Grhl3 由调整了 E-cadherin 表示的机制, E-cadherin 倡导者报告分析被表现,结果出现了那 Grhl3 镇压 E-cadherin 基因表示由对在近似 E-cadherin 倡导者在场的电子盒子直接或间接地有约束力。一起拿,我们的调查结果在癌症房间由 E-cadherin 的 downregulation 在移植和侵略的正式就职为 Grhl3 定义一个主要角色。Pan Zhao Sijia Guo Zhenzhen Tu Lijun Di Xiaoiun Zha Haisheng Zhou Xuejun Zhang 2016Acta Biochimica et Biophysica Sinica2016,0,3:9
11Observations of atmospheric pollutants at Lhasa during 2014-2015:Pollution status and the influence of meteorological factors显示文摘Atmospheric pollutants including SO_2, NO_2, CO, O_3 and inhalable particulate matter(PM2.5 and PM10) were monitored continuously from March 2014 to February 2015 to investigate characteristics of air pollution at Lhasa, Tibetan Plateau. Species exhibited similar seasonal variations except O_3, with the peaks in winter but low valleys in summer. The maximum O_3 concentration was observed in spring, followed by summer, autumn, and winter. The positive correlation between O_3 and PM10 in spring indicated similar sources of them, and was assumed to be turbulent transport. Temperature was the dominant meteorological factor for most species in spring. High temperature accelerates O_3 photochemistry, and favors air disturbance which is conductive to dust resuspension in spring. Relative humidity(RH) and atmospheric pressure were the main meteorological factors in summer. RH showed negative correlations with species, while atmospheric pressure posed opposite situation. Wind speed(WS) was the dominant meteorological factor in autumn, the negative correlations between WS and species indicated diffusion by wind. Most species showed non-significant correlations with meteorological factors in winter, indicating the dependence of pollution on source emission rather than restriction by meteorology. Pollution weather character indicated that emissions were from biomass burning and dust suspension, and meteorological factors also played an important role. Air stream injection from the stratosphere was observed during O_3 pollution period. Air parcels from Southwest Asia were observed during air pollution period in winter. An enhancement in air pollutants such as O_3 would be expected in the future, more attention should be given to countermeasures for prevention of air pollution in the future.Bu Duo Lulu Cui Zhenzhen Wang Rui Li Liwu Zhang Hongbo Fu Jianmin Chen Huifang Zhang A.Qiong 2018Journal of Environmental Sciences2018,30,1:9
12A 2-kb Mycovirus Converts a Pathogenic Fungus into a Beneficial Endophyte for Brassica Protection and Yield Enhancement显示文摘Mycoviruses are viruses that infect fungi,and hypovirulence-associated mycoviruses have the potential to control fungal diseases.However,it is unclear how mycovirus-mediated hypovirulent strains live and survive in the field,and no mycovirus has been applied for field crop protection.In this study,we found that a previously identified small DNA mycovirus(SsHADV-1)can convert its host,Sclerotinia sclerotiorum,from a typical necrotrophic pathogen to a beneficial endophytic fungus.SsHADV-1 downregulates the expression of key pathogenicity factor genes in S.sclerotiorum during infection.When growing in rapeseed,the SsHADV-1-infected strain DT-8 significantly regulates the expression of rapeseed genes involved in defense,hormone signaling,and circadian rhythm pathways.As a result,plant growth is promoted and disease resistance is enhanced.Field experiments showed that spraying DT-8 at the early flowering stage can reduce the disease severity of rapeseed stem rot by 67.6%and improve yield by 14.9%.Moreover,we discovered that SsHADV-1 could also infect other S.sclerotiorum strains on DT-8-inoculated plants and that DT-8 could be recovered from dead plants.These findings suggest that the mycoviruses may have the ability to shape the origin of endophytism.Our discoveries suggest that mycoviruses may influence the origin of endophytism and may also offer a novel strategy for disease control in which mycovirus-infected strains are used to improve crop health and release mycoviruses into the field.Hongxiang Zhang Jiatao Xie Yanping Fu Jiasen Cheng Zheng Qu Zhenzhen Zhao Shufen Cheng Tao Chen Bo Li Qianqian Wang Xinqiang Liu Binnian Tian David B.Collinge Daohong Jiang 2020Molecular Plant2020,13,10:9
13Spectral element analysis on the characteristics of seismic wave propagation triggered by Wenchuan M_s8.0 earthquake显示文摘The 2008 Wenchuan earthquake occurred in an active earthquake zone, i.e., Longmenshan tectonic zone. Seismic waves triggered by this earthquake can be used to explore the characteristics of the fault rupture process and the hierarchical structure of the Earth's interior. We employ spectral element method incorporated with large-scale parallel computing technology, to investigate the characteristics of seismic wave propagation excited by Wenchuan earthquake. We calculate synthetic seismograms with one-point source model and three-point source model respectively. The AK135 model is employed as a prototype of our numerical global Earth model. The Earth's ellipticity, Earth’s medium attenuation, and topography data are taken into consideration. These wave propagation processes are simulated by solving three-dimensional elastic wave governing equations. Three-dimensional visualization of our numerical results displays the profile of the seismic wave propagation. The three-point source, which is proposed from the latest investigations through field observation and reverse estimation, can better demonstrate the spatial and temporal characteristics of the source rupture process than the one-point source. We take comparison of synthetic seismograms with observational data recorded at 16 observatory stations. Primary results show that the synthetic seismograms calculated from three-point source agree well with the observations. This can further reveal that the source rupture process of Wenchuan earthquake is a multi-rupture process, which is composed by at least three or more stages of rupture processes.YAN ZhenZhen ZHANG Huai YANG ChangChun SHI YaoLin 2009Science China Earth Sciences2009,52,6:9
14Expression and significance of fat mass and obesity associated gene and forkhead transcription factor O1 in non-alcoholic fatty liver disease显示文摘Zhang Jielei Li Shan Li Jingyi Han Chao Wang Zhifang Li Chong Wang Xiaoman Liu Zhenzhen Wen Jianguo Zheng Lili 2014Chinese Medical Journal2014,,21:9
15Study on patterns and chemical features of NO effect on marine phytoplankton growth显示文摘This article discusses the patterns of NO effect on marine phytoplankton growth from chemical perspective.The experimental results of four algae,which are Platymonas hal-golandica var.tsingtaoensis,Platymonas subcordiformis,Skeletonema costatum and Nitzschia closterium farma minutissima,are as follows:(i) In f/2 medium or f/50 medium,the growth of these four algae was obviously promoted or inhibited when nitric oxide of different concentrations was added once or twice each day during the cultivation;(ii) The NO effects on the growth of marine phytoplankton are in normal distribution.Different phytoplankton has different optimum NO concentration,which is consistent with the influence of NO on the growth of high plants;(iii) The effect of NO on Platymonas halgolandica var.tsingtaoensi,which is a food alga,is different from that on the red tide algae Skeletonema costatum and Nitzschia closterium farma minutis-sima.The authors put forward a new opinion that every alga has its own NO threshold concen-tration.All the above results may provide new clues to understand the formation of red tide.ZHANG Zhengbin LIN Cai LIU Chunying XING Lei WU Zhenzhen SUN Feng 2005Science China Chemistry2005,48,4:9
16Separation and Precise Measurement of Lithium Isotopes in Three Reference Materials Using Multi Collector-Inductively Coupled Plasma Mass Spectrometry显示文摘Lithium separation technique for three reference materials has been established together with precise determination of lithium isotope using a Neptune multi collector-inductively coupled plasma mass spectrometry (MC-ICP-MS). The solutions of lithium element standard reference materials, potassium, calcium, sodium, magnesium and iron single element, were used to evaluate analytical methods applied. Three separate stages of ion-exchange chromatography were carried out using organic cation-exchange resin (AG 50W-X8). Lithium was enriched for the three stages using different eluants, which are 2.8 M HCl, 0.15 M HCl and 0.5 M HCl in 30% ethanol, respectively. The columns for the first and second stages are made of polypropylene, and those for the third stage are made of quartz. Total reagent volume for the entire chemical process was 35 mL for three reference materials. The recovery yielded for the three stages is 98.9-101.2% with an average of 100.0%, 97.6- 101.9% with an average of 99.9%, and 99.8-103.3% with an average of 100.6%, respectively. The precision of this technique is conservatively estimated to be ±0.72-1.04‰ (2σ population), which is similar to the precision obtained by different authors in different laboratories with MC-ICP-MS. The δ 7 Li values ( 7 Li/ 6 Li relative to the IRMM-016 standard) determined for andesite (AGV-2) and basalt (BHVO-2) are 5.68‰ (n=18), 4.33‰ (n=18), respectively. The δ 7 Li value ( 7 Li/ 6 Li relative to the L-SVEC standard) determined for IRMM-016 is -0.01‰ (n=15). All these analytical results are in good agreement with those previously reported. In addition, the results for the same kinds of samples analyzed at the MLR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, are consistent with those obtained at the Plasma Laboratory, University of Maryland, within analytical uncertainty. According to these experiment results, it is concluded that this proposed procedure is a suitable method for determining the lithium isotopic composition of natural samples.TIAN Shihong HOU Zengqian SU Aina HOU Kejun HU Wenjie LI Zhenzhen ZHAO Yue GAO Yanguang LI Yanhe YANG Dan YANG Zhusen 2012Acta Geologica Sinica(English Edition)2012,86,5:9
17Synergistic effects of elevated homocysteine level and abnormal blood lipids on the onset of stroke显示文摘Hyperhomocysteinemia and abnormal blood lipids are independent risk factors for stroke.However,whether both factors exert a synergistic effect in the onset of stroke remains unclear.The present study is a retrospective analysis of 2 089 cases of stroke and 2 089 control cases of simple intervertebral disk protrusion using a paired multivariate logistic regression method.Adjusting for known confounding variables including the patients’age,gender,smoking status,alcohol consumption status,patient and family medical history,and clinical biochemical indices,elevated homocysteine level was related to the onset of stroke.Patients with elevated homocysteine levels and abnormal blood lipids showed a 40.9%increase in the risk for stroke compared to patients with normal homocysteine levels and blood lipids(odds ratio 1.409;95%confidence interval1.127–1.761).These results indicate that elevated homocysteine and abnormal blood lipids exert synergistic effects in the onset of stroke.Patients with elevated homocysteine levels and abnormal blood lipids are predisposed to stroke.Lu Hao Liming Chen Xiaoyong Sai Zhefeng Liu Guang Yang Rongzeng Yan Lili Wang Caiyun Fu Xuan Xu Zhenzhen Cheng Qiang Wu Shuzhang Li 2013Neural Regeneration Research2013,8,31:9
18Heavy Oil and Oil Sands:Global Distribution and Resource Assessment显示文摘Global recoverable resources of heavy oil and oil sands have been assessed by CNPC using a geology-based assessment method combined with the traditional volumetric method, spatial interpolation method, parametric-probability method etc. The most favourable areas for exploration have been selected in accordance with a comprehensive scoring system. The results show:(1) For geological resources, CNPC estimate 991.18 billion tonnes of heavy oil and 501.26 billion tonnes of oil sands globally, of which technically recoverable resources of heavy oil and oil sands comprise 126.74 billion tonnes and 64.13 billion tonnes respectively. More than 80% of the resources occur within Tertiary and Cretaceous reservoirs distributed across 69 heavy oil basins and 32 oil sands basins. 99% of recoverable resources of heavy oil and oil sands occur within foreland basins, passive continental-margin basins and cratonic basins.(2) Since residual hydrocarbon resources remain following large-scale hydrocarbon migration and destruction, heavy oil and oil sands are characterized most commonly by late hydrocarbon accumulation, the same basin types and source-reservoir conditions as for conventional hydrocarbon resources, shallow burial depth and stratabound reservoirs.(3) Three accumulation models are recognised, depending on basin type: degradation along slope; destruction by uplift; and migration along faults.(4) In addition to mature exploration regions such as Canada and Venezuela, the Volga-Ural Basin and the Pre-Caspian Basin are less well-explored and have good potential for oil-sand discoveries, and it is predicted that the Middle East will be an important region for heavy oil development.LIU Zuodong WANG Hongjun Graham BLACKBOURN MA Feng HE Zhengjun WEN Zhixing WANG Zhaoming YANG Zi LUAN Tiansi WU Zhenzhen 2019Acta Geologica Sinica(English Edition)2019,93,1:9
19Laser Ablation ICP-MS U-Pb Zircon Geochronology of Granitoids and Quartz Veins in the Shihu Gold Mine, Taihang Orogen, North China: Timing of Gold-mineralization and Tectonic Implications显示文摘The Shihu gold deposit, situated in the Taihang Mesozoic orogen of the North China Craton (NCC), is hosted by ductile-brittle faults within Archean metamorphic core complex. The deposit is characterized by gold-bearing quartz-polymetallic sulfides veins. The Mapeng granitoids stock and intermediate-basic dikes intruded the metamorphic basement rocks, and are spatially related to gold mineralization. Detailed laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) U- Pb zircon ages of the granitic rocks, dykes and mineralized quartz veins in the studied area reveal its magmatic and mineralized history. The mineralized quartz veins contain inherited zircons with ages of about 2.55 Ga and 1.84 Ga, probably coming from the basement. These two Precambrian events are coeval with those in other parts of the NCC. The Mapeng granitoid stock, the largest intrusion in the area, was emplaced at ca. 130 Ma, and is coeval with magmatic zircon populations from diorites and quartz diorite pophyrites in the same region. The ca. 130 Ma magmatism and gold mineralization were most likely related to an underplating event that took place in the Taihang orogen at Late Mesozoic. The timing of gold mineralization with respect to felsic magmatism in the area is similar to those observed in other major gold-producing provinces in the NCC. This episode is simultaneous with those in the eastern margin of NCC, indicative of a widespread late Yanshanian metallogenic event that was a response to the Early Cretaceous lithosphere in the eastern NCC, in which the mesothermal gold deposits were formed from similar tectono-magmatic environments.CAO Ye LI Shengrong XIONG Xianxiao LI Zhenzhen LIU Xiaobin YAO Meijuan ZHANG Huafeng 2012Acta Geologica Sinica(English Edition)2012,86,5:8
20Characteristics of entropy generation and heat transfer in a microchannel with fan-shaped reentrant cavities and internal ribs显示文摘Three-dimensional laminar fluid flow and heat transfer in a micro heat sink with cavities and internal ribs are investigated us-ing numerical methods. Moreover, according to the second law of thermodynamics, the model of entropy generation is also established for variable cross section of the microchannel. The simulation encompasses Reynolds number of 198-600, relative cavity height e1/Dhvalues of 0-0.65, relative rib height e2/Dhrange of 0-0.2167. The results show that the effect of relative rib height on entropy generation is significant, while the relative cavity height has little effect on it. The combined effect of cavities and ribs in the microchannel has better performance of heat transfer than the smooth microchannel under similar conditions. Extensive simulations are conducted to collect data on the characteristics of heat transfer and fluid flow in a micro heat sink with cavities and internal ribs. Using these data, correlations for Nusselt number and friction factor in terms of Reynolds number and the geometry of cavity and rib have been developed.XIA GuoDong ZHAI YuLing CUI ZhenZhen 2013Science China(Technological Sciences)2013,56,7:8
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