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Classification of Natural Types of Quercus variabilis
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作者 Jianyun ZHOU 《Plant Diseases and Pests》 CAS 2023年第2期23-26,共4页
[Objectives]The paper was to classify natural types of Quercus variabilis and to study its regularity of variation.[Methods]Through the analysis of correlation coefficient matrix of tree age,DBH,tree height,breast hei... [Objectives]The paper was to classify natural types of Quercus variabilis and to study its regularity of variation.[Methods]Through the analysis of correlation coefficient matrix of tree age,DBH,tree height,breast height and bark thickness,petiole length,leaf width and leaf length,the breast height and bark thickness and petiole length were chosen as the main indices for classifying natural types of Q.variabilis.[Results]There were 4 natural types of Q.variabilis in Shaanxi Province,including long-petiole-thick-bark type,short-petiole-thick-bark type,long-petiole-thin-bark type and short-petiole-thin-bark type.The short-petiole-thick-bark type accounted for the largest proportion in Q.variabilis population(34.44%).On the northern slope of Bashan Mountains and the Huanglong Mountains,the short-petiole-thick-bark type was the dominant type,while on the northern slope of Qinling Mountains the long-petiole-thick-bark type accounted for a larger proportion.[Conclusions]This study will provide a basic foundation for making full use of excellent types of Q.variabilis natural resources. 展开更多
关键词 Quercus variabilis natural type CLASSIFICATION Shaanxi Province
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Natural Gas Types,Distribution Controlling Factors,and Future Exploration in the Western Qaidam Basin 被引量:3
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作者 GUO Zeqing SUN Ping +5 位作者 LI Jian ZHANG Lin LIU Weihong TIAN Jixian ZHANG Shaosheng ZENG Xu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第4期1214-1226,共13页
The Paleogene and Neogene oil and gas in the western Qaidam basin have a regular distribution in three concentric zones from the edge to the center of the basin. Natural gas mainly occurs in the inner zone, and the ga... The Paleogene and Neogene oil and gas in the western Qaidam basin have a regular distribution in three concentric zones from the edge to the center of the basin. Natural gas mainly occurs in the inner zone, and the gas-oil ratio of the northern area of the basin is significantly higher than that of the southern area. Large amounts of carbon isotope data of natural gas, plotted in X- shaped and comprehensive identification diagrams for the southern area and northern area, respectively, were used to identify the types of natural gas. The large-scale distribution of natural gas is highly consistent with the Ro values of major source rocks, but is poorly correlated with the type of organic matter. This indicates that the main controlling factor of natural gas distribution is organic matter maturity, and the kerogen types act as the basis for the formation of different types of natural gas. Paleouplifts and squeezed anticlines near hydrocarbon generation depression centers, which are major natural gas-rich regions, control the migration directions of natural gas, while hydrocarbon migration pathways and fault systems connecting gas sources are the most important factors for natural gas reservoir formation in the inner basin. Therefore, favorable zones for natural gas distribution can be predicted on the basis of the distribution of thermal evolution and the gas generation intensity of major source rocks as well as the structural map. The Shizigou-Youshashan- Yingdong-Dawusi, Youquanzi -Kaitemilike - Youdunzi, and Xiaoliangshan - Nanyishan - Dafengshan structural belts are favorable zones for natural gas accumulation. This study has important theoretical and practical significance for future natural gas exploration. 展开更多
关键词 western Qaidam basin natural gas types distributional characteristics main controlling factors MATURITY favorable zones
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Extranodal natural killer/T-cell lymphoma,nasal type:epidemiology study 被引量:3
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作者 Yao Liao Xiaobo Du Qingfeng Zou 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第5期290-293,共4页
Extranodal natural killer (NK)IT-cell lymphoma, nasal type (ENKTCL) is a rarely kind of non-Hodgkin lymphoma (NHL). It is much more frequent in Asian and Latin American countries than other part of the world. It... Extranodal natural killer (NK)IT-cell lymphoma, nasal type (ENKTCL) is a rarely kind of non-Hodgkin lymphoma (NHL). It is much more frequent in Asian and Latin American countries than other part of the world. It typically affects nasal cavity. In China, one of its endemically places, ENKTCL accounts for 74%-96% of nasal NHL. Patients with ENKTCL usually show a highly aggressive clinical course, and its etiology is unclear. However, it is already proved that ENKTCL is associated with Epstein-Barr virus (EBV) infection, regardless patients', ethnicity and areas. Some studies show that the risk will increase among several occupations, such as farmer, who are frequently exposure to pesticides and chemical solvent and risk can be cut down if taking some protective measures. 展开更多
关键词 nasal lymphoma natural killer (NK)/T-cell type EPIDEMIOLOGY PESTICIDE Epstein-Barr virus (EBV)
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The First Total Synthesis of Five Elegan Type Natural Products
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作者 Jing LI Jiong LAN +1 位作者 Zuo Sheng LIU Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,Lanzhou Univerity, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第7期595-598,共4页
The first total synthesis of five linear diterpenes: eleganolone (1), eleganolone acetate (2), elegandiol (3), eleganonal (4) and epoxyeleganolone (5), was achieved from (E,E)-farnesol (6) via 4 to 6 steps. The key st... The first total synthesis of five linear diterpenes: eleganolone (1), eleganolone acetate (2), elegandiol (3), eleganonal (4) and epoxyeleganolone (5), was achieved from (E,E)-farnesol (6) via 4 to 6 steps. The key step was the alkylation reaction of silyl cyanide with allylic iodide. 展开更多
关键词 PPM HNMR CM IR EIMS The First Total Synthesis of Five Elegan type natural Products MHZ
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Application of butane geochemistry of natural gas in hydrocarbon exploration 被引量:4
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作者 Miao Zhongying Chen Jianfa +3 位作者 Wang Jing Wang Guannan ZhangChen Li Wei 《Petroleum Science》 SCIE CAS CSCD 2012年第4期455-462,共8页
In order to distinguish the source and migration direction of natural gas by geochemical characteristics of butane,the components and carbon isotopes of natural gas from major hydrocarbonbearing basins in China were a... In order to distinguish the source and migration direction of natural gas by geochemical characteristics of butane,the components and carbon isotopes of natural gas from major hydrocarbonbearing basins in China were analyzed.The results showed that:(1) Oil-type gas has i-C 4 /n-C 4 0.8,δ 13 C butane -28‰,δ 13 C i-butane -27‰,δ 13 C n-butane -28.5‰,whereas coal-type gas has i-C 4 /n-C 4 0.8,δ 13 C butane -25.5‰,δ 13 C i-butane -24‰,δ 13 C n-butane -26‰.(2) When δ 13 C i-butane-δ 13 C n-butane is greater than 0,the maturity of oil-type gas is generally more than 2.4% and that of coal-type gas is greater than 1.4%,whereas when the difference is less than 0,the maturity of oil-type gas is generally less than 1.1% and that of coal-type gas is less than 0.8%.(3) When natural gas migrates through dense cap rocks,the value of i-C 4 /n-C 4 increases,whereas when it migrates laterally along a reservoir,the value of i-C 4 /n-C 4 decreases.(4) Sapropelic transition zone gas with composition and carbon isotopic signatures similar to those of oil-type gas in the low thermal evolution stage is found to have a relatively high butane content.(5) The values of i-C 4 /n-C 4 and δ 13 C n-butane δ 13 C i-butane of gas which has suffered biological degradation are significantly higher than those obtained from thermogenic and bio-thermocatalytic transition zone gas.Thus,natural gas of different genetic types can be recognized through component analysis and carbon isotopic signatures of butane,the natural gas maturity can be estimated from the difference in carbon isotopic content between isobutane and n-butane,and the migration direction of natural gas can be determined from i-C 4 /n-C 4 ratios and transport conditions,which can also be used to thermogenic and bio-thermocatalytic transition zone gas. 展开更多
关键词 natural gas N-BUTANE ISOBUTANE carbon isotope genetic types of natural gas migration direction
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Lymphomatoidgastropathy mimicking extranodal NK/T cell lymphoma,nasal type:A case report 被引量:5
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作者 Tomohiro Terai Mitsushige Sugimoto +6 位作者 Hiroki Uozaki Tetsushi Kitagawa Mana Kinoshita Satoshi Baba Takanori Yamada Satoshi Osawa Ken Sugimoto 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第17期2140-2144,共5页
Extranodal natural killer(NK)/T-cell lymphoma,nasal type,exhibits aggressive tumor behavior and carries a poor prognosis.Recently,lymphomatoid gastropathy with NK/T cell infiltration into gastric mucosa has been recog... Extranodal natural killer(NK)/T-cell lymphoma,nasal type,exhibits aggressive tumor behavior and carries a poor prognosis.Recently,lymphomatoid gastropathy with NK/T cell infiltration into gastric mucosa has been recognized as a pseudo-malignant disease which regresses without treatment.Because the conventional immunohistochemical criteria of lymphomatoid gastropathy is similar to that of extranodal NK/T-cell lymphoma nasal type,it is difficult to distinguish between the two conditions by histopathological evaluation only.Here,we report a rare case of lymphomatoid gastropathy in a 57-year-old female.Gastroendoscopy on routine check-up revealed elevated reddish lesions < 1 cm in diameter in the gastric fornix and body.Although repeat endoscopies at 1 and 6 mo later revealed no gastric lesions at any locations without any treatments,at 12 mo later gastric lymphomatoid lesions recurred at gastric fornix and body.Histological examination of endoscopic biopsy specimens at 12 mo showed atypical NK cell infiltration with CD3+,CD4-,CD5-,CD7+,CD8-,CD20-,CD30-,CD56+,CD79a-and T-cell-restricted intracellular antigen-1+ into gastric mucosa.After treatment for Helicobacter pylori(H.pylori) eradication,the lesions disappeared in all locations of the gastric fornix and body over the subsequent 12 mo.Here,we report a case of H.pylori-positive lymphomatoid gastropathy with massive NK-cell proliferation,and also review the literature concerning newly identified lymphomatoid gastropathy based on comparison of extra nodal NK/T-cell lymphoma nasal type.In any case,these lesions are evaluated with biopsy specimens,the possibility of this benign entity should be considered,and excessive treatment should be carefully avoided.Close follow-up for this case of lymphomatoid gastropathy is necessary to exclude any underlying malignancy. 展开更多
关键词 Gastric lymphomatoid gastropathy Gastric natural killer/T-cell lymphoma nasal type Helicobacter pylori Eradication
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Developing phase of China's system of nature reserves in perspective
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作者 Xue-Jun OUYANG Wan-Hui YE +2 位作者 Marc HOCKINGS Chung-Lim LUK Zhong-Liang HUANG 《Forestry Studies in China》 CAS 2013年第4期340-348,共9页
Up until 2009, 2541 nature reserves had been established in China. However, the process of developing this system of nature reserves was not quite smooth. Various kinds of information related to nature reserves, such ... Up until 2009, 2541 nature reserves had been established in China. However, the process of developing this system of nature reserves was not quite smooth. Various kinds of information related to nature reserves, such as annual growth, the type of nature reserves established, motives behind building a nature reserve, legal instructions and the constitution of government sectors, were collected and analyzed in order to highlight the characteristics of the development of our nature reserve system. As a result, we identify three phases and their characteristics, i.e., the initial phase from 1956 to 1978, the establishment phase from 1979 to 1996 and the management standardization phase from 1997 to 2009, could be clearly identified. It is suggested that since the establishment of this comprehensive structural framework in China, the system should be entering a new developing phase. We recommend that more attentions should be paid on how to guarantee effective management and how nature reserves are able to maintain their value and fulfill their objectives in the future. 展开更多
关键词 system of nature reserves China developing phase nature conservation jurisprudence types of nature reSerVe
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