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高原地区如何进行生态保护——从藏族的鱼意识到现代放生鱼的思考 被引量:1
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作者 宋晓霞 《和田师范专科学校学报》 2015年第2期111-114,共4页
放生在藏族的传统文化中形成了积淀,成为适应高原环境的一种法则,社会的不断进步,及佛教传入藏族有了"放生"的习俗而延续至今。社会在不断向前发展,高原的生态保护不能仅仅依靠传统的生态意识来维持,这需要科学的手段介入,在... 放生在藏族的传统文化中形成了积淀,成为适应高原环境的一种法则,社会的不断进步,及佛教传入藏族有了"放生"的习俗而延续至今。社会在不断向前发展,高原的生态保护不能仅仅依靠传统的生态意识来维持,这需要科学的手段介入,在保护当地物种的前提下,来满足其生态平衡的需求。 展开更多
关键词 “放生”的习俗 生存环境 耐性定律 温度 生态平衡
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Study on the Nitrogen Release Law of Bamboo Charcoal-coated Urea and Its Biological Utilization Effects
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作者 纪锐琳 朱义年 +1 位作者 张爱莉 张学洪 《Agricultural Science & Technology》 CAS 2007年第3期53-58,67,共7页
[Objective] The study about the nitrogen releasing law of bamboo-charcoal coated urea and the biologic utilization effect was to find the coated urea with high efficiency,low price and simple production technology.[Me... [Objective] The study about the nitrogen releasing law of bamboo-charcoal coated urea and the biologic utilization effect was to find the coated urea with high efficiency,low price and simple production technology.[Method]Two kinds of bamboo-charcoal coated urea(BCCU)with different coating thickness were made by using bamboo-charcoal and macromolecule polymer as coating material.The experiments of soil eluviate,ammonia volatilization in corn field and potted plant of corn were conducted to study the nitrogen releasing law and the biologic utilization effect of self-made BCCU.[Result]The BCCU showed some slow-release capability and their accumulated nitrogen releasing rates in 29 d were 9.93%-16.27% lower than that of normal urea.Compared with the normal urea,the volatilization rate of ammonia in BCCU reduced to 16.66%-31.8%,the biomass of corn and nitrogen utilization rate increased by 12.8%-24.1% and 10.5%-16.99%,respectively.[Conclusion]Bamboo-charcoal in coated urea not only had some slow-release capability,but also had some adsorbability,which would reduce the eluviation and volatilization of nitrogen and protect environment from N pollution. 展开更多
关键词 Bamboo-charcoal Coated urea Utilization rate Eluviation loss Ammonia volatilization
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Effects of Bacillus amyloliquefaciens Biofertilizer on Brassica juncea var. multiceps Growth and N_2O Emission from Soil 被引量:2
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作者 白志辉 王璠 +3 位作者 曹建喜 吴尚华 徐圣君 马双龙 《Agricultural Science & Technology》 CAS 2015年第4期727-732,749,共7页
In this study, Bacil us amyloliquefaciens A3 was continual y incubated in shake fIasks contalning wastewater from sweet potato starch production as an ef-fective biofertiIizer for cuItivation of Brassica juncea var. m... In this study, Bacil us amyloliquefaciens A3 was continual y incubated in shake fIasks contalning wastewater from sweet potato starch production as an ef-fective biofertiIizer for cuItivation of Brassica juncea var. multiceps(XueIihong). Based on pot experiments in the greenhouse, the effects of chemical fertiIizers (CN), biofertiIizer (BF), inactivated broth (BI), starch wastewater (SW) and the combination of biofertiIizer and chemical fertiIizer (BC) on the yield, NO3- content and NO2- con-tent of XueIihong, soiI physicochemical properties and N2O emission were investi-gated. The resuIts showed that the yield of XueIihong in BC and CN treatments was improved by five times compared with CK; BF and SW treatments had insignifi-cant impact on the yield of XueIihong. Compared with CN treatment, BCL treatment exhibited simiIar improving effects on the yield of XueIihong, in which NO3- content of XueIihong and soiI was reduced by 16.4%-73.6% and 22%-29%, which reduced the risk of nitrogen eIuviations in soiI; average N2O fIux (FPV30) in BCL treatment was reduced by 58.3%-73.1% compared with CN treatment. In concIusion, B. amy-loliquefaciens is a feasibIe Iow-cost biofertiIizer for sustalnabIe vegetabIe farming with a great potential for starch wastewater utiIization. 展开更多
关键词 Bacil us amyloliquefaclens Wastewater from sweet potato starch pro-ductlon Brassica juncea var. multiceps Blofertliizer N2O emisslon
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Combustion behavior and NO emission characteristic of biomass in O_2/CO_2 atmosphere
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作者 段锋 孙肖茹 +2 位作者 张友松 胡爱凤 钱建嵩 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期200-203,共4页
The thermogravimetric analyzer and horizontal tube furnace are used to study the effects of operation parameters such as temperature, fuel type, and oxygen concentration on the combustion and NO emission characteristi... The thermogravimetric analyzer and horizontal tube furnace are used to study the effects of operation parameters such as temperature, fuel type, and oxygen concentration on the combustion and NO emission characteristics of the rice husk, rice straw, and peanut shell in the O2/CO2 atmosphere. The results show that the combustion performances of volatile matter and fixed carbon of the three biomasses increase with the increase in the 02 content. The mean NO emission increases sharply when the reaction temperature increases from 700 to 800℃. However, it increases slightly when the temperature exceeds 800 ℃. Meanwhile, the mean NO emission and nitrogen conversion decrease with the increase in the nitrogen content in biomass. The mean NO emission changes little with different oxygen concentrations, and the NO emissions of the three biomasses are all lower than the requirement for the minimum NO emission. Increasing the oxygen concentration favors the biomass combustion in the O2/CO2 atmosphere, and oxygen concentration has little effect on the NO emission. 展开更多
关键词 BIOMASS COMBUSTION THERMOGRAVIMETRIC NOemission O2/CO2
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pH Stability of Defibrase_ in Aqueous Solution Determined by En-zyme-linked Immunosorbent Assay
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作者 赵会英 郑俊民 +2 位作者 徐晖 魏刚 赵怀清 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期144-147,共4页
Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respect... Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respectively. The change of antigenic activities and coagulating activities of Defibrase in the same buffer solutions (pH 6, 7 and 8, with the exception of pH 3.6) showed similar tendency to decline with the time. Concentrated Defi-brase was relatively stable at neutral pH 6~7, more than 95% of its initial activities (100BUmL-1) was kept after a 10-day storage at 40 oC, whereas in pH 3.6 and pH 9 buffer solutions, diluted Defibrase was very labile. Addition of Triton X-100 or bovine serum albumin could effectively prevent loss of Defibrase by minimizing adsorption of De-fibrase to plastic surface (P<0.005). Concentration of Defibrase could also affect its stability in aqueous solutions. 展开更多
关键词 STABILITY DEFIBRASE ELISA
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A dynamic analysis of environmental losses from anthropogenic lead flow and their accumulation in China 被引量:1
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作者 梁静 毛建素 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1125-1133,共9页
Substance flow analysis was applied to analyzing the lead emissions in 2010. It turns out that in 2010, for every 1 kg of lead consumed, 0.48 kg lead is lost into the environment. The emissions in 2010 were estimated ... Substance flow analysis was applied to analyzing the lead emissions in 2010. It turns out that in 2010, for every 1 kg of lead consumed, 0.48 kg lead is lost into the environment. The emissions in 2010 were estimated to be 1.89×10^6 t, which were mainly from use (39.20%) and waste management&recycling (33.13%). The accumulative lead in 1960-2010 from the anthropogenic flow was estimated and the results show that the total accumulative lead in this period amounted to 19.54×10^6 t, which was equivalent to 14.26 kg and 2.04 g/m^2 at the present population and territory. 展开更多
关键词 substance flow analysis EMISSION historical accumulation dissipative uses life cycle
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Effects of Reduced Nitrogen Fertilization and Biochar Application on CO_2 and N_2O Emissions from a Summer Maize-Winter Wheat Rotation Field in North China 被引量:1
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作者 韩雪 范靖尉 +4 位作者 白晋华 任寰宇 李迎春 刁田田 郭李萍 《Agricultural Science & Technology》 CAS 2016年第12期2800-2808,共9页
This experiment was conducted in Xinxiang, Henan from June 2013 to June 2014. Total four treatments were designed including farmers ’ common practice (F, 250 kg/hm^2), 80% F (LF, 200 kg/hm^2), 80% F+biochar (LF... This experiment was conducted in Xinxiang, Henan from June 2013 to June 2014. Total four treatments were designed including farmers ’ common practice (F, 250 kg/hm^2), 80% F (LF, 200 kg/hm^2), 80% F+biochar (LFC) and no fertilizer (CK) to measure the dynamic emissions of CO2 and N2O from a summer maize-winter wheat field by static chamber-gas chromatography method. The results showed that the soil CO2 emission was 21.8-1 022.7 mg/(m^2·h), and was mainly influenced by soil temperature and moisture content. During the growth of summer maize, the soil CO2 emission was more significantly affected by soil moisture con-tent; and in winter wheat growing season, it was more significantly affected by soil temperature in the top 5 cm. The LF and LFC treatments significantly reduced the soil cumulative CO2 emission, especial y during the growth of winter wheat. Fertiliza-tion and irrigation were the main factors influencing the soil N2O emission. The soil N2O emission during the fertilization period accounted for 73.9%-74.5% and 40.5%-43.6% of the soil cumulative N2O emission during the summer maize-and winter wheat-growing season, respectively. The peak of emission fluxes was determined by fertilization amount, while the occurrence time of emission peak and emission re-duction effect were influenced by irrigation. The LF treatment reduced the soil cu-mulative N2O emission by 15.7%-16.8% and 18.1%-18.5% during the growth period of summer maize and winter wheat, respectively. Reduced nitrogen fertilization is an effective way for reducing N2O emission in intensive high-yielding farmland. Under a suitable nitrogen level (200 kg/hm^2), the application of biochar showed no significant effect on the soil N2O emission in a short term. The N2O emission factors of the L and LF treatments were 0.60% and 0.56%, respectively. ln the intensive high-yield-ing farmland of North China, reducing the nitrogen application amount is an appro-priate measure to mitigate greenhouse gas emissions without crop yield loss. 展开更多
关键词 Reduced nitrogen fertilization BIOCHAR Greenhouse gas emissions N2O emission Winter wheat-summer maize
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Prediction and control of rock burst of coal seam contacting gas in deep mining 被引量:5
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作者 WANG En-yuan LIU Xiao-fei ZHAO Ein-lai LIU Zhen-tang 《Journal of Coal Science & Engineering(China)》 2009年第2期152-156,共5页
By analyzing the characteristics and the production mechanism of rock burstthat goes with abnormal gas emission in deep coal seams,the essential method of eliminatingabnormal gas emission by eliminating the occurrence... By analyzing the characteristics and the production mechanism of rock burstthat goes with abnormal gas emission in deep coal seams,the essential method of eliminatingabnormal gas emission by eliminating the occurrence of rock burst or depressingthe magnitude of rock burst was considered.The No.237 working face was selected asthe typical working face contacting gas in deep mining;aimed at this working face,a systemof rock burst prediction and control for coal seam contacting gas in deep mining wasestablished.This system includes three parts:① regional prediction of rock burst hazardbefore mining,② local prediction of rock burst hazard during mining,and ③ rock burstcontrol. 展开更多
关键词 deep mining coal seam contacting gas rock burst gas abnormal emission rock burst prediction and control system
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Gastric motor effects of ghrelin and growth hormone releasing peptide 6 in diabetic mice with gastroparesis 被引量:13
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作者 Wen-Cai Qiu Zhi-Gang Wang Wei-Gang Wang Jun Yan Qi Zheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第9期1419-1424,共6页
AIM:To investigate the potential therapeutic significance of ghrelin and growth hormone releasing peptide 6 (GHRP-6) in diabetic mice with gastric motility disorders. METHODS: A diabetic mouse model was established by... AIM:To investigate the potential therapeutic significance of ghrelin and growth hormone releasing peptide 6 (GHRP-6) in diabetic mice with gastric motility disorders. METHODS: A diabetic mouse model was established by intraperitoneal (ip) injection of alloxan. Diabetic mice were injected ip with ghrelin or GHRP-6 (20-200 μg/kg), and the effects on gastric emptying were measured after intragastric application of phenol red. The effect of atropine, NG-nitro-L-arginine methyl ester hydrochloride (L-NAME) or D-Lys3-GHRP-6 (a growth hormone secretagogue receptor (GHS-R) antagonist) on the gastroprokinetic effect of ghrelin or GHRP-6 (100 μg/kg) was also investigated. The effects of ghrelin or GHRP-6 (0.01-10 μmol/L) on spontaneous or carbachol-induced contractile amplitude were also investigated in vitro, in gastric fundic circular strips taken from diabetic mice. The presence of growth hormone secretagogue receptor 1a transcripts in the fundic strips of diabetic mice was detected by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: We established a diabetic mouse model with delayed gastric emptying. Ghrelin and GHRP-6 accelerated gastric emptying in diabetic mice with gastroparesis. In the presence of atropine or L-NAME, which delayed gastric emptying, ghrelin and GHRP-6 (100 μg/kg) failed to accelerate gastric emptying. D-Lys3-GHRP-6 also delayed gastric emptying induced by the GHS-R agonist. Ghrelin and GHRP-6 increased the carbachol-induced contractile amplitude in gastric fundicstrips taken from diabetic mice. RT-PCR confirmed the presence of GHS-R mRNA in the strip preparations. CONCLUSION: Ghrelin and GHRP-6 increase gastric emptying in diabetic mice with gastroparesis, perhaps by activating peripheral cholinergic pathways in the enteric nervous system. 展开更多
关键词 Gastric emptying GHRELIN Growth hormone releasing peptide 6 Growth hormone secretagogue receptor Diabetic mice
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Biological Characteristies of Methane Emission of Oryzasativa,Panicumcrus-galliand Cyperusdif for misGrown on PaddySoil 被引量:2
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作者 MINHANG CHENMEI-CI 《Pedosphere》 SCIE CAS CSCD 1994年第2期165-172,共8页
Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativ... Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativa >C. difformis, with the former two 11 and 8 times as much as that of the latter, respectively. And it was just opposite tothat of the methane-forming activities of roots of the three plants. The diurnal changes of methane emission of thethree plants were relatively consistent with valleys during 11:00-14:00 and midnight and peaks during 8:00-11: 00,14:00- 20:00 and about 5:00 early morning. The methanogenic activites in rhizospheric soils were higher than those innonrhizospheric soils with P. crus-galli and O. sativa, but not with C. difformis. The pathways of methane release ofP. crus-galli and O . sativa were probably through the top gaps near the junctions of nodal plate and leaf sheath, how-ever in C. difformistopgaps from which methane could escape into atmosphere were not found. 展开更多
关键词 activity of methane formation Cyperus difformis methane emission Oryza sativa Panicum crus-galli
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Emerging Challenges in ESD Protection for RF ICs in CMOS 被引量:2
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作者 王自惠 林琳 +2 位作者 王昕 刘海南 周玉梅 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期628-636,共9页
On-chip electrostatic discharge (ESD) protection design has become an emerging challenge for radio-frequency (RF) integrated circuits (IC) design as IC technologies migrate into the very-deep-sub-micron (VDSM)... On-chip electrostatic discharge (ESD) protection design has become an emerging challenge for radio-frequency (RF) integrated circuits (IC) design as IC technologies migrate into the very-deep-sub-micron (VDSM) regime and RF ICs move into multi-GHz operations. The key problem originates from the complex interaction between the ESD protection circuitry and the core RF IC circuit under protection. This paper discusses the recent development in RF ESD protection research and design,outlining emerging challenges, new design methods,and novel RF ESD protection solutions. 展开更多
关键词 electrostatic discharge ESD protection RF ESD PARASITIC
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Stocking density affects the growth performance and metabolism of Amur sturgeon by regulating expression of genes in the GH/IGF axis 被引量:2
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作者 REN Yuanyuan WEN Haishen +1 位作者 LI Yun LI Jifang 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期956-972,共17页
The effects of stocking density on the growth and metabolism of Amur sturgeon were assessed. Amur sturgeon were grown for 70 days at three dif ferent stocking densities(low stocking density, LSD: 5.5 kg/m^3; medium st... The effects of stocking density on the growth and metabolism of Amur sturgeon were assessed. Amur sturgeon were grown for 70 days at three dif ferent stocking densities(low stocking density, LSD: 5.5 kg/m^3; medium stocking density, MSD: 8.0 kg/m^3; and high stocking density, HSD: 11.0 kg/m^3), and the biometric index, muscle composition, and serum biochemical parameters were evaluated. In addition, pituitary, liver, and muscle samples were collected for gene cloning and expression analyses. After 70 days of growth, the fish maintained at HSD had significantly lower fi nal body weight and specifi c growth rate, and a higher feed conversion ratio than those of the fish in the MSD and LSD groups. The HSD group had the lowest lipid and protein concentrations in serum and muscle. The serum cortisol concentration increased significantly in the HSD group, indicating that the stress-response system was activated in these fish. There was no change in the concentration of serum insulin-like growth factor 2(IGF-2), while the concentrations of serum growth hormone(GH) and insulin-like growth factor 1(IGF-1) decreased in the HSD group. The full-length cDNAs of G H and IGF-2 genes(995-bp and 1 207-bp long, respectively), were cloned and analyzed. In the HSD group, the expressions of GH in the pituitary and growth hormone receptor( GHR) and IGF-1 in the liver were down-regulated at the end of the 70-day experiment. In the HSD group, the transcript level of IGF-2 significantly decreased in the liver, but did not change in muscle. Overall, our results indicated that a HSD negatively af fects the growth performance and leads to changes in lipid and protein metabolism in Amur sturgeon. The down-regulated expression of genes related to the GH/IGF axis may be responsible for the poor growth performance of Amur sturgeon under crowding stress. 展开更多
关键词 Amur sturgeon stocking density growth metabolism growth hormone (GH) insulin-like growth factor(IGF) AXIS
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Animal Radioecology in the Exclusion Zone Since the Chernobyl Catastrophe 被引量:1
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作者 Leonid Frantsevich 《Zoological Research》 CAS CSCD 北大核心 2006年第6期647-655,共9页
We review 20 year long investigations by the Schmalhausen Institute of Zoology on radioecological and ecological consequences of the Chernobyl catastrophe for wild animals in the Exclusion Zone (EZ) around the nucle... We review 20 year long investigations by the Schmalhausen Institute of Zoology on radioecological and ecological consequences of the Chernobyl catastrophe for wild animals in the Exclusion Zone (EZ) around the nuclear plant. Using previous observations on bird migrations through Ukraine, we assessed the 137^Cs and 90^Sr carry-out with migrants from the EZ. In addition, we selected animal species as standard indicators of the state of the environment to map : 1 ) contamination of vertebrates with 137^Cs in the EZ and 2) beta-activity of mollusc shells indicating 90^Sr, in the whole Dnieper drainage area, in the Kiev Administrative Region, and in the EZ. We revealed regular seasonal and long-term trends, relative radionuclide accumulation by different species, transfer and accumulation factors, and used these measurements to diminish the enormous variation and complexity of the data. Secondary ecological changes in forest, devastated by direct irradiation, were caused by the crash of trophic chains and an outbreak of insect pests on dead or sick trees. Ninety-nine percent of the EZ area was not affected directly by irradiation. Ecological changes in this area have been caused by evacuation of the public, cessation of agriculture and forest management, and decontamination on a large scale. After initial changes, animal density and distribution have been stabilized at a limit restricted by natural resources, predators and poachers. A herd of Przewalski horses was successfully introduced into the EZ years ago. We renewed the protected state of nature reserved sites, which existed before, and proposed to expand the area of nature reservation. 展开更多
关键词 Chernobyl catastrophe RADIOECOLOGY BIOINDICATION
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Expressions and their significance of PTTG and PC proteins in glioma 被引量:2
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作者 Rufei Dai Shiming Zhang 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第2期110-113,共4页
Objective: To investigate the expressions and their relationship of pituitary tumor transforming gene (PTTG) and proliferating cell nuclear antigen (PCNA) in glioma. Methods: The protein expressions of PTTG and ... Objective: To investigate the expressions and their relationship of pituitary tumor transforming gene (PTTG) and proliferating cell nuclear antigen (PCNA) in glioma. Methods: The protein expressions of PTTG and PCNA were detected by immunostaining assay using streptavidin-peroxidase (SP) method in 80 cases of glioma. Results: The positive rates of PTTG in grades Ⅰ-Ⅳ gliomas were 56.3%, 68.2%, 80.8%, and 100.0% respectively, and the protein expression of PTTG increased with the increasing of the pathological grade (X^2= 9.602, P 〈 0.05); The positive rates of PCNA protein were 37.5%, 54.5%, 69.2%, and 93.8% respectively, and the protein expression of PCNA increased with the increasing of the pathological grade (X2 = 12.147, P 〈 0.01). The expression of PTTG had positive correlation with the expression of PCNA protein (~s = 0.557, P 〈 0.01). Conclusion: The expressions of PTTG and PCNA proteins were related to malignant degree of glioma, and may cooperate with each other in the tumorigenesis and progression and can be considered as the indicators of the biological behaviors in glioma. 展开更多
关键词 pituitary tumor transforming gene (PTTG) proliferating cell nuclear antigen (PCNA) GLIOMA IMMUNOHISTOCHEMISTRY
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Greenhouse Gas Emissions from Sewage Treatment in China during 2000-2009 被引量:1
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作者 ZHOU Xing ZHENG You-Fei +2 位作者 KANG Na ZHOU Wei YIN Ji-Fu 《Advances in Climate Change Research》 SCIE 2012年第4期205-211,共7页
Based on the statistics from the China Statistical Yearbook (2000-2009) on environment and methods recommended by the IPCC, the amounts of greenhouse gas (GHG) emissions from domestic and industrial sewage treatme... Based on the statistics from the China Statistical Yearbook (2000-2009) on environment and methods recommended by the IPCC, the amounts of greenhouse gas (GHG) emissions from domestic and industrial sewage treatment in China are estimated for the period of 2003-2009. CO2 emissions per capita from sewage treatment plants are also analyzed. The results show that the GHG emissions from sewage treatment plants increased steadily from 2003 to 2009; N20 emissions from domestic sewage are the major source of the total GHG emissions from domestic sewage; CH4 emissions from domestic sewage increase with the greatest speed; CH4 emissions from paper and pulp industry are the major source of industrial sewage emissions; CO2 emissions per capita increase constantly from 2003 to 2009. 展开更多
关键词 sewage treatment CH4 N20 EMISSIONS
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Principal Component Analysis of Major Pollutants Discharge Amount in Major Cities 被引量:1
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作者 于淼 金童 《Agricultural Science & Technology》 CAS 2017年第7期1260-1262,共3页
With the development of industry in China, the emission issues of indus- trial wastewater has got more and more attention. Excessive levels of pollutants in wastewater are urgent problem to be solved. Together with th... With the development of industry in China, the emission issues of indus- trial wastewater has got more and more attention. Excessive levels of pollutants in wastewater are urgent problem to be solved. Together with the emissions of do- mestic wastewater, the discharge amount of pollutants has exceeded standard in many cities, which not only pollutes the water resources, but also greatly threatens the environment, and does great harm to people's health. The principal component analysis was conducted based on the principal components extracted from the data of major pollutants emission conditions in the wastewater of major cities from the China Statistical Yearbook 2014. 展开更多
关键词 Principal component analysis Pollutant discharge amount Industrial wastewater: Domestic wastewater
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The correlation between nitrogen species in coke and NO_x formation during regeneration 被引量:6
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作者 Teng Li Chaohe Yang +3 位作者 Xiaobo Chen Libo Yao Wei Liang Xuemei Ding 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第5期606-611,共6页
Nitrogen oxides (NOx) emission during the regeneration ofcoked fluid catalytic cracking (FCC) catalysts is an en- vironmental issue. In order to identify the correlations between nitrogen species in coke and diffe... Nitrogen oxides (NOx) emission during the regeneration ofcoked fluid catalytic cracking (FCC) catalysts is an en- vironmental issue. In order to identify the correlations between nitrogen species in coke and different nitrogen- containing products in tail gas, three coked catalysts with multilayer structural coke molecules were prepared in a fixed bed with model compounds (o-xylene and quinoline) at first. A series of characterization methods were used to analyze coke, including elemental analysis, FT-IR, XPS, and TG-MS. XPS characterization indicates all coked catalysts present two types of nitrogen species and the type with a higher binding energy is related with the inner part nitrogen atoms interacting with acid sites. Due to the stronger adsorption ability on acid sites for basic nitrogen compounds, the multilayer structural coke has unbalanced distribution of carbon and ni- trogen atoms between the inner part and the outer edge, which strongly affects gas product formation. At the early stage of regeneration, oxidation starts from the outer edge and the product NO can be reduced to N2 in high CO concentration. At the later stage, the inner part rich in nitrogen begins to be exposed to 02. At this period, the formation of CO decreases due to lack of carbon atoms, which is not beneficial to the reduction of NO. There- fore, nitrogen species in the inner part of multilayer structural coke contributes more to NOx formation. Based on the multilayer structure model of coke molecule and its oxidation behavior, a possible strategy to control NOx emission was discussed merely from concept. 展开更多
关键词 NOx Basic nitrogen compounds FCC catalyst COKING REACTION MULTILAYER
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Response of N_2O Emissions of Farmland Ecosystem on Temperature Rising
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作者 刘柳松 施建成 《Agricultural Science & Technology》 CAS 2012年第9期1962-1966,共5页
[Objective] The aim was to study on response of N2O emissions of farm- land ecosystem on temperature rising. [Methed] In farmland ecosystem in Huaibei City in Anhui Province, N2O emission by twelve varieties of crop o... [Objective] The aim was to study on response of N2O emissions of farm- land ecosystem on temperature rising. [Methed] In farmland ecosystem in Huaibei City in Anhui Province, N2O emission by twelve varieties of crop on temperature was researched with DeNitrification-DeComposition (NDC). [Result] Response of dry- land crop on temperature rising can be divided into three categories, as follows: The first category, N2O emission of crop changed little during the temperature increasing, for example, from 0 to 3 %;, the emissions by potatoes, cotton, maize and rapeseed increased little and decreased little when temperature changed from 1.5 to 3 ℃. Crops of the second category declined with temperature increasing in N2O emission, for example, N2O emission decreased by 8.1% with temperature increasing from 0 to 3 ℃, including sugar cane, tobacco, wheat, soybean and pea. In third category, N2O emission of crop grew with temperature increasing, for example, the emission of rice, vegetables and fruit trees increased by 22.8% when the temperature grew from 0 to 3 ℃. [Conclusion] The research indicated that N2O emission in ecosystem of drv farmland increased little with temoerature risina. 展开更多
关键词 Arid land Farmland ecosystem N20 emission Temperature rising
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Environmental life cycle assessment of Indian coal-fired power plants 被引量:6
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作者 Udayan Singh Naushita Sharma Siba Sankar Mahapatra 《International Journal of Coal Science & Technology》 EI 2016年第2期215-225,共11页
Coal is the backbone of the Indian power sector. The coal-fired power plants remain the largest emitters of carbon dioxide, sulfur dioxide and substantial amounts of nitrogen oxides, which are associated with climate ... Coal is the backbone of the Indian power sector. The coal-fired power plants remain the largest emitters of carbon dioxide, sulfur dioxide and substantial amounts of nitrogen oxides, which are associated with climate and health impacts. Various CO2 mitigation technologies (carbon capture and storage--CCS) and SO2/NOx mitigation technologies (flue gas desulfurization and selective catalytic reduction) have been employed to reduce the environmental impacts of the coal-fired power plants. Therefore, it is imperative to understand the feasibility of various mitigation technologies employed. This paper attempts to perform environmental life cycle assessment (LCA) of Indian coal-fired power plant with and without CO2, SO2 and NOx mitigation controls. The study develops new normalization factors for India in various damage categories, using the Indian emissions and energy consumption data, coupled with the emissions and particulate emission to come up with a final environmental impact of coal-fired electricity. The results show a large degree of dependence on the perspective of assessment used. The impact of sensitivities of individual substances and the effect of plant efficiency on the final LCA results is also studied. 展开更多
关键词 Lifeinventory Fluecycle assessment Coal-fired power plants - Carbon capture and storage Environmental impact Plantgas desulfurization
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The cardiovascular action of hexarelin 被引量:3
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作者 Yuanjie MAO Takeshi Tokudome Ichiro Kishimoto 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2014年第3期253-258,共6页
Hexarelin, a synthetic growth hormone-releasing peptide, can bind to and activate the growth hormone secretagogue receptor (GHSR) in the brain similar to its natural analog ghrelin. However, the peripheral distribut... Hexarelin, a synthetic growth hormone-releasing peptide, can bind to and activate the growth hormone secretagogue receptor (GHSR) in the brain similar to its natural analog ghrelin. However, the peripheral distribution of GHSR in the heart and blood vessels suggests that hexarelin might have direct cardiovascular actions beyond growth hormone release and neuroendocrine effects. Furthermore, the non-GHSR CD36 had been demonstrated to be a specific cardiac receptor for hexarelin and to mediate its cardioprotective effects. When compared with ghrelin, hexarelin is chemically more stable and functionally more potent. Therefore, it may be a promising therapeutic agent for some car-diovascular conditions. In this concise review, we discuss the current evidence for the cardiovascular action of hexarelin. 展开更多
关键词 Hexarelin Cardiovascular disease Growth hormone secretagogue receptor CD36
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