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滇西北山加铜矿区水文地质条件评述
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作者 王进进 《中国市场》 2016年第30期187-188,共2页
维西县位于云南的西北部,地处世界自然遗产"三江并流"之腹地,文章综合研究了维西山加铜矿区的地质、矿体产出特征和水文地质条件,铜矿体主要产于侏罗系上统(J_(2+3))和白垩系下统景星组(K_1j)地层中,区内断裂构造发育。矿区... 维西县位于云南的西北部,地处世界自然遗产"三江并流"之腹地,文章综合研究了维西山加铜矿区的地质、矿体产出特征和水文地质条件,铜矿体主要产于侏罗系上统(J_(2+3))和白垩系下统景星组(K_1j)地层中,区内断裂构造发育。矿区地下水为碎屑岩裂隙水型,富水性较弱,矿区地下水对铜矿的开采影响不大。 展开更多
关键词 山加铜矿 地质特征 水文条件 云南维西
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云南省维西县山加铜矿地质特征及找矿标志
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作者 宋学齐 尹焕菊 《云南地质》 2019年第1期69-75,共7页
云南维西县山加铜矿矿体呈脉状、层状、似层状、透镜状赋存于断层构造破碎带中,矿体近矿围岩为侏罗系中统花开左组(J_2h)和白垩系下统景星组第一段(K_1j^1),构造控矿明显,属构造破碎带控制的中-低温热液充填、交代富集型铜矿床。矿区内... 云南维西县山加铜矿矿体呈脉状、层状、似层状、透镜状赋存于断层构造破碎带中,矿体近矿围岩为侏罗系中统花开左组(J_2h)和白垩系下统景星组第一段(K_1j^1),构造控矿明显,属构造破碎带控制的中-低温热液充填、交代富集型铜矿床。矿区内物化探异常、构造破碎带的围岩蚀变、以及前人遗留下的采坑、废矿硐、炼铜炉渣等是本矿区重要的找矿标志。 展开更多
关键词 构造控矿 热液型矿床 找矿标志 云南维西 山加
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云南维西山加铜矿床地质特征及成因浅析 被引量:2
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作者 王进进 陈玉梁 +1 位作者 李映海 陈载林 《价值工程》 2016年第8期160-163,共4页
维西山加铜矿位于三江成矿带,Ⅴ—Ⅶ号矿体均赋存于花开左组碎屑岩夹碳酸盐岩中,位于近南北向张性断层F3破碎带中;Ⅷ号矿体赋存于景星组碎屑岩中,位于北西向张性断层F5破碎带中。矿体呈脉状、透镜状产出,严格受断裂构造的控制。矿床中... 维西山加铜矿位于三江成矿带,Ⅴ—Ⅶ号矿体均赋存于花开左组碎屑岩夹碳酸盐岩中,位于近南北向张性断层F3破碎带中;Ⅷ号矿体赋存于景星组碎屑岩中,位于北西向张性断层F5破碎带中。矿体呈脉状、透镜状产出,严格受断裂构造的控制。矿床中矿质在沉积成岩时已初步富集,后经地下热卤水对富含铜的沉积层进行溶滤和搬运,在有利的地层和构造薄弱部位进行充填、交代而形成矿床。此外,用爆裂法和均匀法对孔雀石、辉铜矿进行测温,其成矿温度在175~250℃之间,应属中低温热液矿床。 展开更多
关键词 中低温热液矿床 地质特征 矿床成因 构造控矿 山加铜矿 云南维西
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Sorbitol-Electrolyte-Additive Based Reversible Zinc Electrochemistry
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作者 Qiong Sun Hai-Hui Du +5 位作者 Tian-Jjiang Sun Dian-Tao Li Min Cheng Jing Liang Hai-Xia Li Zhan-Liang Tao 《电化学(中英文)》 CAS 北大核心 2024年第7期28-37,共10页
The unstable zinc(Zn)/electrolyte interfaces formed by undesired dendrites and parasitic side reactions greatly hinder the development of aqueous zinc ion batteries.Herein,the hydroxy-rich sorbitol was used as an addi... The unstable zinc(Zn)/electrolyte interfaces formed by undesired dendrites and parasitic side reactions greatly hinder the development of aqueous zinc ion batteries.Herein,the hydroxy-rich sorbitol was used as an additive to reshape the solvation structure and modulate the interface chemistry.The strong interactions among sorbitol and both water molecules and Zn electrode can reduce the free water activity,optimize the solvation shell of water and Zn^(2+)ions,and regulate the formation of local water(H_(2)O)-poor environment on the surface of Zn electrode,which effectively inhibit the decomposition of water molecules,and thus,achieve the thermodynamically stable and highly reversible Zn electrochemistry.As a result,the assembled Zn/Zn symmetric cells with the sorbitol additive realized an excellent cycling life of 2000 h at 1 mA·cm^(-2)and 1 mAh·cm^(-2),and over 250 h at 5 mA.cm^(-2)and 5 mAh.cm^(-2).Moreover,the Zn/Cu asymmetric cells with the sorbitol additive achieved a high Coulombic efficiency of 99.6%,obtaining a better performance than that with a pure 2 mol-L^(-1)ZnSO_(4)electrolyte.And the constructed Zn/poly1,5-naphthalenediamine(PNDA)batteries could be stably discharged for 2300 cycles at 1 A g^(-1)with an excellent capacity retention rate.This result indicates that the addition of 1 mol-L^(-1)non-toxic sorbitol into a conventional ZnSO_(4)electrolyte can successfully protect the Zn anode interface by improving the electrochemical properties of Zn reversible deposition/decomposition,which greatly promotes its cycle performance,providing a new approach in future development of high performance aqueous Zn ion batteries. 展开更多
关键词 Aqueous zinc ion batteries DENDRITE Sorbitol additive Solvation regulation Interface modulation
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RC beam strengthened with pre-stressed CFP under the secondary load 被引量:5
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作者 LONG Bang-yun YUAN Guang-lin ZHU Dan-yu 《Journal of China University of Mining and Technology》 EI 2008年第4期618-622,共5页
Feasibility of using pre-stressed carbon fiber plates to strengthen reinforced concrete beams was studied. Based on the characteristics of carbon fiber plates, we developed a pre-stress clamp and a device for applying... Feasibility of using pre-stressed carbon fiber plates to strengthen reinforced concrete beams was studied. Based on the characteristics of carbon fiber plates, we developed a pre-stress clamp and a device for applying the pre-stress. Contrast tests were conducted between ordinary carbon fiber plates and a pre-stressed carbon fiber plate and between secondary loaded carbon fiber plates and a concrete beam strengthened with a secondary loaded carbon fiber plate. On this basis, we analyzed the failure pattern, the width of cracks and their distribution, the cracking load, the yield load, the limit load and the relation between load and deflec- tion. The results indicate that using pre-stressed carbon fiber plates to strengthen concrete beams is feasible and effective. 展开更多
关键词 PRE-STRESS CFP secondary load strengthening RC beam
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泰山磐石散加减结合地屈孕酮对气血两虚型习惯性流产妊娠影响研究 被引量:12
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作者 廖泽兰 杨志玲 《中华中医药学刊》 CAS 北大核心 2022年第1期200-203,共4页
目的探究泰山磐石散加减结合地屈孕酮对气血两虚型习惯性流产患者妊娠影响。方法研究合计纳入92例气血两虚型习惯性流产患者,均由医院2017年1月—2020年2月收治,采取随机数字表法将其分为两组,予以对照组患者(46例)地屈孕酮治疗,予以观... 目的探究泰山磐石散加减结合地屈孕酮对气血两虚型习惯性流产患者妊娠影响。方法研究合计纳入92例气血两虚型习惯性流产患者,均由医院2017年1月—2020年2月收治,采取随机数字表法将其分为两组,予以对照组患者(46例)地屈孕酮治疗,予以观察组患者(46例)泰山磐石散加减结合地屈孕酮治疗,比较两组患者临床疗效、治疗前后中医症状(自然流产、月经异常、精神萎靡、头晕耳鸣、畏寒肢冷、夜尿频繁等)积分变化、妊娠结局、治疗前后患者孕酮(P)、雌二醇(E_(2))水平变化、治疗前后患者免疫功能指标变化以及患者治疗满意程度。结果观察组患者治疗总有效率(97.83%,45/46)高于对照组(84.78%,39/46)(P<0.05);观察组患者顺利分娩率(97.83%,45/46)高于对照组(82.61%,38/46)(P<0.05);治疗前,两组患者自然流产、月经异常、精神萎靡、头晕耳鸣、畏寒肢冷、夜尿频繁等中医症状积分、P及E_(2)水平、白介素-4(IL-4)、γ干扰素(IFN-γ)、IFN-γ/IL-4等免疫功能指标比较,P>0.05,治疗后各组患者自然流产、月经异常、精神萎靡、头晕耳鸣、畏寒肢冷、夜尿频繁等中医症状积分、P及E_(2)水平、IL-4、IFN-γ、IFN-γ/IL-4等免疫功能指标均改善,观察组患者治疗后自然流产、月经异常、精神萎靡、头晕耳鸣、畏寒肢冷、夜尿频繁等中医症状积分、P及E_(2)水平、IL-4、IFN-γ、IFN-γ/IL-4等免疫功能指标均优于对照组(P<0.05);观察组患者治疗后满意率(93.48%,43/46)显著高于对照组患者(78.26%,36/46)(P<0.05)。结论泰山磐石散加减结合地屈孕酮治疗气血两虚型习惯性流产效果良好,可提升患者顺利分娩率,患者恢复好,免疫力提升,患者十分满意,值得应用。 展开更多
关键词 气血两虚型习惯性流产 泰山磐石散加减 地屈孕酮 疗效 顺利分娩率 免疫功能
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Shifting cultivation effects on soil fungi and bacterial population in Chittagong Hill Tracts, Bangladesh 被引量:1
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作者 Sohag Miah Soma Dey S.M.Sirajul Haque 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期311-318,397,共9页
A study was conducted at two pair sites of Chittagong Hill Tracts in Bangladesh to find out the effects of shifting cultivation on soil fungi and bacterial population. The first pair of sites with shifting culti-vatio... A study was conducted at two pair sites of Chittagong Hill Tracts in Bangladesh to find out the effects of shifting cultivation on soil fungi and bacterial population. The first pair of sites with shifting culti-vation and village common forest-managed by indigenous community was at Madhya Para in Rangamati district and the second pair of sites with the shifting cultivated land and village common forest at Ampu Para in Bandarban district of Chittagong Hill Tracts. At both the locations with two different land uses, soil textures in surface (0?10 cm) and sub-surface (10?20 cm) soils varied from sandy loam to sandy clay loam. Soil pH and moisture content were lower in shifting cultivated land com-pared to village common forest. The results also showed that both fungal and bacterial population in surface and subsurface soils was significantly (p ≤ 0.05) lower, in most cases, in shifting cultivated land compared to village common forest at both Madhya Para and Ampu Para. At Ranga-mati and Bandarban in shifting cultivated lands, Colletrotrichum and Fusarium fungi were absent and all the bacterial genus viz. Coccus, Bacillus and Streptococcus common in two different locations with dif-ferent land uses. Common identified fungi at both the land uses and locations were Aspergillus, Rhizopus, Trichoderma and Penicillium. Further study can be done on the other soil biota to understand the extent of environmental deterioration due to shifting cultivation. 展开更多
关键词 shifting cultivation FUNGI BACTERIA soil biological properties village common forest Chittagong Hill Tracts BANGLADESH
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Sorbitol Hydrogenolysis to Glycols over Baisic Additive Promoted Ni-based Catalysts 被引量:2
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作者 Xiao-feng Cao Qi Zhang +4 位作者 Dong Jiang Qi-ying Liu Long-long Ma Tie-jun Wang De-bao Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第3期338-344,I0002,共8页
A series of Ni based catalysts with different supports and basic additives were prepared by sequential impregnation method. The catalysts were characterized by XRD, BET, H2-TPR and CO2-TPD techniques. It was found tha... A series of Ni based catalysts with different supports and basic additives were prepared by sequential impregnation method. The catalysts were characterized by XRD, BET, H2-TPR and CO2-TPD techniques. It was found that the introduction of basic additives enhanced the basicities of catalyats and promoted the dispersities of Ni particles by strong interaction between Ni2+ and basic additives. Among the Ni based catalysts, 10%Ni/10%La203/ZrO2 showed the superior performance in sorbitol hydrogenolysis. The synergistic effect of Ni and La203 was proven to play an essential role in selective synthesis of EG and 1,2-PG. In the optimal reaction condition, the catalyst presented 100% sorbitol conversion and over 48% glycols (EG and 1,2-PG) yield. The kinetics study of polyols (sorbitol, xylitol and glycerol) hydrogenolysis showed that polyols with more hydroxyl number have higher activity and products distribution was final results of kinetic balance, which could give us some inspiration abeut how to change the products selectivity. 展开更多
关键词 Sorbitol hydrogenolysis GLYCOLS Ni catalyst Support Base promoter
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Heating Stage Experimental Study of Melt Inclusions in Feldspars from Three Holocene Eruptions of Changbaishan Tianchi Volcano 被引量:1
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作者 Li Ni Nicole Metrich Fan Qicheng 《Earthquake Research in China》 2008年第2期153-163,共11页
There occurred several eruptions from Changbaishan Tianchi volcano in Holocene, and at least three of them were believed to be true according to the formal studies. The products of three eruptions were yellow comendit... There occurred several eruptions from Changbaishan Tianchi volcano in Holocene, and at least three of them were believed to be true according to the formal studies. The products of three eruptions were yellow comenditic pumice of - 5000a B.P. (Eruption Ⅰ ), gray comenditic pumice and pyroclastic flow of - 1000a B.P. ( Eruption II, i.e. the millennium explosive eruption), black trachy pumice and welded tuff of - 300a B.P. ( Eruption Ⅲ ) respectively. There were a large number of melt inclusions found in phenocrysts, which differ in size and color. The Leitz 1350 heating stage experiments for melt inclusions in host feldspars from three Holocene eruptions of Changbaishan Tianchi volcano imply that there were little differences between the homogenization temperatures of melt inclusions from Eruptions Ⅰ and Ⅲ, whereas it was rather complicated for Eruption H, i.e. there might be two kinds of melt with different homogenization temperature periods, which gave the evidence for the assumption that the explosive millennium eruption of Tianchi volcano was triggered by injection and mixing of two different magmas. The experimental results also indicate that ( 1 ) small melt inclusion is easy to be homogenized, while the large one, especially the one with lots of daughter crystals, is rather difficult to be homogenized; (2) homogenization temperature closely correlates with the size of melt inclusion within host crystal, with the temperature point switching from high heating rate to low heating rate, and correlates with whether it is the first time to obtain homogenization as well; and (3) a melt inclusion can get different homogenization temperatures when it is repeatedly heated. Even more, the next homogenization temperature is usually higher than the former one, which testifies the phenomenon that hydrogen migration occurs during repeated heating. 展开更多
关键词 Changbaishan Tianchi volcano Alkaline feldspar Melt inclusion Heating stage Homogenization temperature
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Traditional farming in the mountainous region of Bangladesh and its modifications 被引量:1
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作者 MISBAHUZZAMAN Khaled 《Journal of Mountain Science》 SCIE CSCD 2016年第8期1489-1502,共14页
Shifting cultivation is a traditional farming system practiced in the tropical mountainous areas. Although it has been widely perceived as an economically inefficient and environmentally harmful agricultural productio... Shifting cultivation is a traditional farming system practiced in the tropical mountainous areas. Although it has been widely perceived as an economically inefficient and environmentally harmful agricultural production system, recent science reviews, however, indicate that the deleterious impacts of shifting cultivation on environment may have been overestimated. Despite the pressures of agricultural intensification in areas where shifting cultivation occurs, farmers across the tropics still maintain this traditional farming system. The objective of this study was to explore existing traditional shifting cultivation practices and their various modifications including the innovative farming techniques developed by farmers in the Chittagong Hill Tracts(CHTs), the mountainous region of Bangladesh, and examine their importance with respect to recent socio-economic and environmental changes. The study revealed that shifting cultivation still exists as the most dominant farming method which supports livelihoods and culture of the hill ethnic people. However, demand for more food and household income to meet livelihood needs of an increasing population combined with a rapid deterioration of soil and water quality over decades contributed to development of innovative farming practices through fallow land farming, crop substitution, agroforestry and homestead gardening in the CHTs. Through these farming techniques farmers maintain a strong relationship with traditional knowledge system embedded in the ageold shifting cultivation practices. Today state policies and market forces act in favor of replacement of traditional farming with intensive cash crop agriculture. It seems that disappearance of traditional farming practices from the hills may threaten local biodiversity and food security. It may be recommended that shifting cultivation should be encouraged in areas where they have potential for contributing to preservation of native biodiversity and ecosystem services, and protection of local peoples' food security and cultural identity. 展开更多
关键词 Shifting cultivation Chittagong HillTracts AGROFORESTRY Food security
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Improving the Size and Market Value of an Underutilised Yam (Dioscorea esculenta) in Ghana: Implications for Crop Breeding and Production Choices 被引量:2
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作者 Kwamina Banson Kenneth Danso 《Journal of Life Sciences》 2013年第7期732-741,共10页
Yam, Dioscorea esculenta which is a high value commodity is a threatened species in Ghana, due to several factors including neglect on the part of science, technology, research and development. Different doses of radi... Yam, Dioscorea esculenta which is a high value commodity is a threatened species in Ghana, due to several factors including neglect on the part of science, technology, research and development. Different doses of radiation were use to improve the size and market value of D. esculenta to promote it effective use and enhance effective conservation. We observed through repeated experiments that irradiation of yam planting material at 40 Gy gave the best results producing a M1 generation with a decreased number of tubers but with an increased tuber size per vine. Some yam characteristics are valued more than others, and prices vary across species, time, and market sites. Tuber weight exhibits an increasing marginal value and price per kilogram increases above an optimum size; therefore, yam producers and dealers derive additional reward from extra-large tubers. We conclude that, to effectively access and benefit from urban markets, producers should focus on the improved size and conical shaped-tubers, which are easy to process and meet the aesthetic qualities preferred by urban consumers. The implications for research on improved variety development to reduce poverty and for crop and resource management practices are drawn. 展开更多
关键词 Dioscorea esculentus MARKET MUTATION PRODUCTIVITY threatened species.
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Carboniferous Alaskan-type complex along the Sino–Mongolian boundary,southern margin of the Central Asian Orogenic Belt 被引量:6
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作者 Yuruo Shi Linlin Li +4 位作者 Alfred Kroner Jing Ding Wei Zhang Zengbao Huang Ping Jian 《Acta Geochimica》 EI CAS CSCD 2017年第2期276-290,共15页
We present zircon ages and geochemical data for the Hongshishan Carboniferous Alaskan-type mafic–ultramafic complex exposed in the Beishan area along the Sino–Mongolian boundary, southern margin of the Central Asian... We present zircon ages and geochemical data for the Hongshishan Carboniferous Alaskan-type mafic–ultramafic complex exposed in the Beishan area along the Sino–Mongolian boundary, southern margin of the Central Asian Orogenic Belt. This complex mainly consists of dunite,harzburgite, lherzolite, wehrlite, and gabbro, which intrudes Early Carboniferous volcanic rocks and reveals a zoned structure. Zircons of a gabbro sample yielded a 206Pb/238 U age of 357 ± 4 Ma, reflecting the time of Early Carboniferous magmatism. Zircon ages were also obtained for an andesite(322 ± 3 Ma) and a basaltic andesite(304 ± 2 Ma).High initial Nd isotope whole-rock values suggest that the Hongshishan gabbro [e_(Nd(t))= +9.6-+10.2] and basalt[eNd(t)= +10.0-+10.8] were derived from a depleted mantle source. Slightly lower eNd(t)values for the ultramafic rocks [eNd(t)= +8.5-+8.7] suggest some interaction of the parental magma with the continental crust. In contrast, the Late Carboniferous Quershan samples in this area represent subduction-related arc volcanic rocks with Adakite-like compositions. The early Carboniferous Hongshishan Alaskan-type complex was interpreted to represent the remnants of a magma chamber that crystallized at the base of a mature island arc, whereas the Quershan island arc volcanic rockssuggest the resurrection of the subduction process after arccontinent collision and uplift of the roots of the arc. 展开更多
关键词 Alaskan-type complex CARBONIFEROUS Zircon age Sino-Mongolian boundary CAOB
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Solar Forcing on Makkah AI-Mukaramah Flash Floods
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作者 Shahinaz Yousef Yasser H.O. Algafari +1 位作者 Zaki AI-Mostafa Mutaz Kordi 《Journal of Earth Science and Engineering》 2012年第2期77-83,共7页
Severe solar events manifested by highly energetic X-Ray events accompanied by coronal mass ejections and proton flares caused flash floods in Makkah AI-Mukaramab, A1-Madinah AI-Munawarah and Jeddah. The responses can... Severe solar events manifested by highly energetic X-Ray events accompanied by coronal mass ejections and proton flares caused flash floods in Makkah AI-Mukaramab, A1-Madinah AI-Munawarah and Jeddah. The responses can be prompt, delayed or prompt-delayed, suggesting that the protons entered the troposphere either through the opening of a direct gate in the magnetosphere to the location concer.led due to magnetic reconnection, through the polar gates or through those two paths respectively. The authors suggest that there is a magnetic anomaly in Makkah AI-Mukaramah area which makes it liable to be subjected to flash floods. The width of the solar streams determines the width of the gate opened in the magnetosphere via magnetic reconnection and thus narrow streams affect only one location of the three cities while extended width streams can cause flash floods in all of Makkah AI-Mukaramah AI-Madinah AI Munawarah and Jeddah. In addition, the November 24-26 Jeddah flash flood could be attributed to a prompt event due to a moderately fast solar stream that arrived the earth on those days. 展开更多
关键词 Makkah AI-Mukaramah Al-Madinah AI-Munawarah Jeddah coronal mass ejections X-ray events flash floods.
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Comparison of Milan and UCSF criteria for liver transplantation to treat hepatocellular carcinoma 被引量:3
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作者 Tarkan Unek Sedat Karademir +5 位作者 Naciye Cigdem Arslan Tufan Egeli Gulsen Atasoy Ozgul Sagol Funda Obuz Ibrahim Astarcioglu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第37期4206-4212,共7页
AIM:To assess the validity of the Milan and University of California San Francisco(UCSF) criteria and examine the long-term outcome of orthotopic liver transplantation(OLT) in patients with hepatocellular carcinoma(HC... AIM:To assess the validity of the Milan and University of California San Francisco(UCSF) criteria and examine the long-term outcome of orthotopic liver transplantation(OLT) in patients with hepatocellular carcinoma(HCC) in a single-center study.METHODS:This study is a retrospective review of prospectively collected data.Between 1998 and 2009,56 of 356 OLTs were performed in patients with HCC.Based on pathological examination of liver explants,patients were retrospectively categorized into 3 groups:Milan +(n = 34),Milan-/UCSF +(n = 7) and UCSF-(n = 14).RESULTS:Median follow-up period was 39.5(1-124) mo.The 5-year overall survival rates in the Milan +,Milan-/UCSF + and UCSF-groups were 87.7%,53.6% and 33.3%,respectively(P < 0.000).Within these groups,tumor recurrence was determined in 5.8%,14.3% and 40% of patients,respectively(P < 0.011).Additionally,the presence of microvascular invasion within the explanted liver had a negative effect on the 5-year disease free survival(74.7% vs 46.7%,P < 0.044).CONCLUSION:The Milan criteria are reliable in the selection of suitable candidates for OLT for the treatment of HCC.For cases of OLT involving living donors,the UCSF criteria may be applied. 展开更多
关键词 Hepatobiliary radiology Hepatobiliary surgery Hepatobiliary pathology Hepatocellular carcinoma Liver malignancy Liver transplantation Living donor liver transplantation Living related liver transplantation Oncologic surgery Survival TRANSPLANT
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Natural Resources Depletion in Hill Areas of Bangladesh:A Review 被引量:3
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作者 Shampa BISWAS Mark E.SWANSON Harald VACIK 《Journal of Mountain Science》 SCIE CSCD 2012年第2期147-156,共10页
Hilly or mountainous terrain occupies around 12% of the area of Bangladesh.Natural resources associated with Bangladesh's hill are forest resources,biodiversity,minerals,and agricultural crops.Natural resources ha... Hilly or mountainous terrain occupies around 12% of the area of Bangladesh.Natural resources associated with Bangladesh's hill are forest resources,biodiversity,minerals,and agricultural crops.Natural resources have been exploited in the recent four decades due to excessive clearing of hill forest cover,resulting in loss of species richness, impacts related to increased water flow variability, increased hill slope erosion and flooding intensity, and a gradual decrease in the extent of hill area in Bangladesh.This review explores the major causes and effects of depletion of natural resources by linking drivers,pressures and the related impacts.A review has been conducted to structure the effects on the hilly areas and describe the responses to minimize them in the associated DPSIR framework.Population growth has been identified as a major driver contributing to high deforestation rates.This may negatively effect agricultural productivity and increase the frequency of serious flooding.Slash and burn cultivation also impacts the regeneration of evergreen forests,which may accelerate soil erosion. Due to this and other factors,local people are facing a deficits of natural resources(food,fodder,fuel wood and water),which exacerbates the effects of poverty. Future research should try to facilitate decision making for sustainable utilization of natural resources management in the hilly areas of Bangladesh. Additional conservation measures should be developed to increase the resilience of ecosystems at national and regional levels. 展开更多
关键词 Hill environment DEFORESTATION Land degradation Hill restoration and conservation DPSIR
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Study on mechanism of reinforcing sides to control floor heave of extraction opening
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作者 冯涛 《Journal of Coal Science & Engineering(China)》 2005年第1期1-3,共3页
Roadway surrounding rock is a compound structure consisted of roof, floor and sides. The sides of extraction opening is the weak coal mass, which affect immediately the stability of floor. It was simulated by numerica... Roadway surrounding rock is a compound structure consisted of roof, floor and sides. The sides of extraction opening is the weak coal mass, which affect immediately the stability of floor. It was simulated by numerical calculation for the strength of sides coal to affect the floor heave, the higher strength of sides coal is, the lower degree of floor heave was. So it was put forward reinforcing sides to control floor heave of extraction opening, and it was proved by engineering practice that the floor heave of deep extraction opening can be controlled to a certain degree by reinforcing sides of roadway. 展开更多
关键词 extraction opening floor heave reinforcing sides
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Comparative analysis of some selected macronutrients of soil in orange orchard and degraded forests in Chittagong Hill Tracts,Bangladesh 被引量:5
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作者 Mohammad Shaheed Hossain Chowdhury Shampa Biswas +3 位作者 Md. Abdul Halim S. M. Sirajul Haque Nur Muhammed Masao Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第1期27-30,共4页
Status of organic carbon (C), total nitrogen (N), available potassium (K), calcium (Ca) and phosphorus (P) in three different depths (0-5 cm, 5-15 cm and 15?30 cm) on two hill slopes of 35% and 55% in orange orchard c... Status of organic carbon (C), total nitrogen (N), available potassium (K), calcium (Ca) and phosphorus (P) in three different depths (0-5 cm, 5-15 cm and 15?30 cm) on two hill slopes of 35% and 55% in orange orchard cultivated by the Mro tribe of Chittagong Hill Tracts (CHTs) were evaluated and compared with those in degraded bush forests, through digging three profiles in each land use. The content of all the five nutrients was found to be higher in the soil of orange orchard than in the soil of forest. But the variation was not consistent for both the slopes. The content varied depth wise also, having the highest value in surface soil in case of both the land uses on both the slopes. A mean available K content was significantly higher in orange orchard than in forest on 55% slope, while it was lower on 35% slope. Surface soil contained the nutrients of K and Ca with the amount of 0.2905-mg·g^(-1) soil and 3.025-mg·g^(-1)soil respectively in the orchard, while 0.1934-mg·g^(-1) soil and 1.6083-mg·g^(-1) soil were respectively in the forest. Organic carbon and total nitrogen were found more or less similar in surface soil on both the land uses showing a slight difference. Available P was found only in orange orchard, and in forest it was too little in amount to detect by the spectrophotometer. The degraded forests were poor in nutrient content due to high rate of soil erosion, which would be possible to be improved by bringing it under tree cover as proved by the adaptation of orange orchard there. 展开更多
关键词 Orange orchard Degraded forests Soil depth SLOPE BANGLADESH
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Regeneration status of a sub-tropical Anogeissus latifolia forest in Garhwal Himalaya,India
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作者 Munesh Kumar Mukesh Joshi N.P.Todaria 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第4期439-444,522,共7页
The present study deals with the regeneration status of a sub- tropical forest located between 950-1100 m above sea level in Garhwal Himalaya. The vegetation was quantitatively analyzed on four different aspects i.e.,... The present study deals with the regeneration status of a sub- tropical forest located between 950-1100 m above sea level in Garhwal Himalaya. The vegetation was quantitatively analyzed on four different aspects i.e., east, west, north and south. Results of the study indicated that across the aspects, Anogeissus latifolia was dominant in tree, sapling and seedling layers in all the aspects, except north aspect where Pinus roxburghii and Terminalia tomentosa were dominant in tree and seedling layers, respectively. The highest tree layer density (380 plant.ha^-1) was recorded on south aspect and lowest (260 plant.ha^-1) on west aspect. In shrub layer, highest density was on east aspect (1790 plant.ha-1) and lowest on west aspect (970 plant.hal). Tree and shrub layer diversity ranged between 0.846 to 1.710 and 1.943 to 2.847, respectively. The relative lopping intensity (%) was higher in Anogeissus latifolia (45%- 57% as compared to 4%-33% in other species) which is the most important tree species on all aspects, except north aspect. The present study also reveals that if the current rate of exploitation continues, the species like Anogeissus latifolia may be replaced by other species and drastic changes may occur in species composition and regeneration of the forest. The anthropogenic pressure, aspect and soil nutrients have caused changes in regeneration status and species composition of forests. 展开更多
关键词 Anogeissus latifolia Garhwal Himalaya TROPICAL REGENERATION
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Study on Expansion of Steam Cracking Unit to 660 kt/a at Yanshan Petrochemical Company
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作者 Cao Xianghong(SINOPEC Corp., Beijing 100011) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2003年第3期9-22,共14页
Yanshan Petrochemical Company after having expanded its 300 kt/a steam cracking unit to 450 kt/a in 1994 is still experiencing such problems as low feedstock flexibility, high energy consumption and smaller scale of e... Yanshan Petrochemical Company after having expanded its 300 kt/a steam cracking unit to 450 kt/a in 1994 is still experiencing such problems as low feedstock flexibility, high energy consumption and smaller scale of ethylene unit.In order to fully improve technical capability of steam crackers, reduce energy consumption, improve feedstock flexibility and increase production capacity, a lot of technical revamp cases on steam cracking were studied and compared.Revamp of relevant facilities has expanded the ethylene capacity to the target of 660 kt/a with the actual capacity reaching 710 kt/a. This revamp project has remarkably reduced the energy consumption, which is capable of using naphtha, light diesel fuel, heavy diesel fuel and the hydrocracked tail oil as the steam cracking feedstock. This project is the first to apply refrigeration by means of a mixed cooling agent and has succeeded in using C, catalytic rectification/hydrogenation technology, which has given an impetus to the progress of steam cracking industry in the world. 展开更多
关键词 steam cracking ETHYLENE UNIT EXPANSION
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A comprehensive investigation of loading variance influence on fuel consumption and gas emissions in mine haulage operation 被引量:5
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作者 Soofastaei A. Aminossadati S.M. +1 位作者 Kizil M.S. Knights P. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期995-1001,共7页
The data collected from haul truck payload management systems at various surface mines show that the payload variance is significant and must be considered in analysing the mine productivity, diesel energy consumption... The data collected from haul truck payload management systems at various surface mines show that the payload variance is significant and must be considered in analysing the mine productivity, diesel energy consumption, greenhouse gas emissions and associated costs. The aim of this study is to determine the energy and cost saving opportunities for truck haulage operations associated with the payload variance in surface mines. The results indicate that there is a non-linear relationship between the payload variance and the fuel consumption, greenhouse gas emissions and associated costs. A correlation model, which is independent of haul road conditions, has been developed between the payload variance and the cost saving using the data from an Australian surface coal mine. The results of analysis for this particular mine show that a significant saving of fuel and greenhouse gas emissions costs is possible if the standard deviation of payload is reduced from the maximum to minimum value. 展开更多
关键词 Energy consumption Haul truck Surface mine Greenhouse gas emissions Cost
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