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结合数据挖掘分析《备急千金要方》痼冷积热篇方药特点 被引量:3
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作者 姜雯婕 杨勇 《中医药学报》 CAS 2020年第7期27-31,共5页
《备急千金要方》开创了脏腑辨证论治理论体系,是研究孙思邈组方思路和方药配伍特色的重要文献。本文以《备急千金要方》痼冷积热篇病症方药作为研究对象,采用数据挖掘技术结合文献分析的研究方法,总结了痼冷积热篇方剂的总体特点,探讨... 《备急千金要方》开创了脏腑辨证论治理论体系,是研究孙思邈组方思路和方药配伍特色的重要文献。本文以《备急千金要方》痼冷积热篇病症方药作为研究对象,采用数据挖掘技术结合文献分析的研究方法,总结了痼冷积热篇方剂的总体特点,探讨了痼冷积热的病机及组方用药配伍特色。痼冷以肠胃久寒冷积,积热以热邪积聚胃腑,波及上下,治疗痼冷以温里散寒,善用桂枝、附子、生姜、乌头、干姜等药物,积热以清泻热积为主,常用黄芩、天花粉、大黄、石膏等药物,组方重视前人经验,审因创新药法,随症配伍泻下攻积、蠲饮止呕、补益气血等药物,注重特殊的制服方法,以驱邪护正为要,达到邪正兼顾,对临床诊疗有积极的指导意义。 展开更多
关键词 备急千金要方 冷积 组方思路 用药特点
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Cold/Warm Change Characteristics in Crop Growing Season in Heilongjiang Province During 1961-2009 被引量:3
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作者 那济海 国世友 侯绪明 《Agricultural Science & Technology》 CAS 2011年第6期914-919,共6页
[Objective] The aim of the study was to find out the cold/warm change characteristics in crop growing season and their relationship with food production in Heilongjiang Province.[Method] The temporal and spatial varia... [Objective] The aim of the study was to find out the cold/warm change characteristics in crop growing season and their relationship with food production in Heilongjiang Province.[Method] The temporal and spatial variation on the accumulated temperature steadily above 10 ℃ and its lasting days,the beginning date,the ending dates were investigated,and the relationship between food production and cold/warm climate in Heilongjiang Province during 1961-2009 was further analyzed.[Result] The results showed that the provincial average accumulated temperature steadily above 10 ℃ has increased by 355.4 ℃,the lasting days of accumulated temperature steadily above 10 ℃ has extended by 13d,and the beginning date has advanced by 8 d,while the ending date has delayed by 5 d in Heilongjiang Province during 49 years.Climate warming began from the 1980s,and the most significant period of climate warming was after the 1990s.The food production is closely related to cold/warm climate in Heilongjiang Province.[Conclusion] The climate warming was significant in crop growing season of Heilongjiang Province in the past 49 years,providing more favorable climatic conditions for the agricultural production. 展开更多
关键词 Cold/warm change Accumulated temperature Food production
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浅论影响中药疗效的药物因素
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作者 周学东 《临床医药实践》 2010年第9X期1250-1251,共2页
祖国医学博大精深,影响很大,疗效显著,在中国五千年漫长的历史长河中,对中华民族的繁衍生息,发展壮大,都发挥了深远影响。然而,尽管中医辩证准确,处方精当,疗效有时候却不尽如人意,这是为什么呢?就让我们来讨论一下影响中药疗效的诸多... 祖国医学博大精深,影响很大,疗效显著,在中国五千年漫长的历史长河中,对中华民族的繁衍生息,发展壮大,都发挥了深远影响。然而,尽管中医辩证准确,处方精当,疗效有时候却不尽如人意,这是为什么呢?就让我们来讨论一下影响中药疗效的诸多因素吧! 展开更多
关键词 中药疗效 药物因素 中医辩证 泻下作用 酒炙丹参 炮制方法 辛凉解表 毒性成分 阳明腑实 攻下冷积
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巴豆霜
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《光明中医》 2016年第7期1013-1013,共1页
性味:辛,热;有大毒。归经:归胃、大肠经。功能:峻下冷积,逐水退肿,豁痰利咽;外用蚀疮。主治:用于寒积便秘,乳食停滞,腹水臌胀,二便不通,喉风,喉痹;外治痈肿脓成不溃,疥癣恶疮,疣痣。用法与用量:0.1~0.3g。多入丸散用。外用适量。... 性味:辛,热;有大毒。归经:归胃、大肠经。功能:峻下冷积,逐水退肿,豁痰利咽;外用蚀疮。主治:用于寒积便秘,乳食停滞,腹水臌胀,二便不通,喉风,喉痹;外治痈肿脓成不溃,疥癣恶疮,疣痣。用法与用量:0.1~0.3g。多入丸散用。外用适量。注意:孕妇禁用;不宜与牵牛子同用。贮藏:置阴凉干燥处。 展开更多
关键词 蚀疮 喉痹 二便不通 峻下 疣痣 退肿 利咽 冷积 豁痰 寒积
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巧用大蒜治肠胃炎
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作者 代金刚 《家庭医药(快乐养生)》 2015年第7期17-17,共1页
夏季是肠胃炎的高发季节,病人一般会以腹痛、呕吐、腹泻为主,腹泻一日数次或十数次。多是由于食用生冷食物造成的。需要注意腹泻后应多补充水分,喝冷饮也要节制。《随息居饮食谱》中记载,大蒜'生者辛热,熟者甘温,除寒湿,辟阴邪,下... 夏季是肠胃炎的高发季节,病人一般会以腹痛、呕吐、腹泻为主,腹泻一日数次或十数次。多是由于食用生冷食物造成的。需要注意腹泻后应多补充水分,喝冷饮也要节制。《随息居饮食谱》中记载,大蒜'生者辛热,熟者甘温,除寒湿,辟阴邪,下气暖中,消谷化肉,破恶血,攻冷积。治暴泻腹痛, 展开更多
关键词 肠胃炎 随息居饮食谱 补充水 冷积 甘温 阴邪 寒湿 生者 消谷 消痞
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Preliminary Study on the Accumulation Characteristics of Mineral Elements in Potted Poa crymophila under Drought and Water Stress
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作者 李天才 曹广民 +2 位作者 林丽 李以康 柯浔 《Agricultural Science & Technology》 CAS 2017年第12期2216-2218,共3页
[Objective] This study was conducted to explain the mechanism of the accumulation characteristics of mineral elements in alpine grassland plants. [Method] Cultivated alpine grassland plant, Poa crymophila, was treated... [Objective] This study was conducted to explain the mechanism of the accumulation characteristics of mineral elements in alpine grassland plants. [Method] Cultivated alpine grassland plant, Poa crymophila, was treated with drought and wa- ter stress, and then the samples were collected and analyzed. [Result] Compared with the control group, under drought and water stress, multiple mineral elements tended to accumulate and increase, and there were significant differences in the contents of Cu, Mn, Ni and P (P〈0.05). [Conclusion] Under drought and water stress, mineral elements in potted Poa crymophila tended to accumulate and in- crease, which is the adaption and response of Poa crymophila to drought and water stress, as well as the re-verification of the starvation effect hypothesis of mineral effects. The starvation effect of mineral elements is one of the endogenic forces for the accumulation and differentiation of mineral elements in grassland plants. 展开更多
关键词 Potted Poa crymophila Mineral elements Accumulation characteristic Drouaht: Water stress
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Fabrication of ultrafine-grained AA1060 sheets via accumulative roll bonding with subsequent cryorolling 被引量:7
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作者 Qing-lin DU Chang LI +2 位作者 Xiao-hui CUI Charlie KONG Hai-liang YU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第11期3370-3379,共10页
Ultrafine-grained(UFG)AA1060 sheets were fabricated via five-cycle accumulative roll bonding(ARB)and subsequent three-pass cold rolling(298 K),or cryorolling(83 K and 173 K).Microstructures of the aluminum samples wer... Ultrafine-grained(UFG)AA1060 sheets were fabricated via five-cycle accumulative roll bonding(ARB)and subsequent three-pass cold rolling(298 K),or cryorolling(83 K and 173 K).Microstructures of the aluminum samples were examined via transmission electron microscopy,and their mechanical properties were measured via tensile and microhardness testing.Results indicate that ultrafine grains in ARB-processed sheets were further refined by subsequent rolling,and the grain size became finer with reducing rolling temperature.The mean grain size of 666 nm in the sheets subjected to ARB was refined to 346 or 266 nm,respectively,via subsequent cold rolling or cryorolling(83 K).Subsequent cryorolling resulted in ultrafine-grained sheets of higher strength and ductility than those of the sheets subjected to cold rolling. 展开更多
关键词 microstructure AA1060 sheet ultrafine-grained materials CRYOROLLING accumulative roll bonding
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Effect of deposition rate on microstructure and mechanical properties of wire arc additive manufacturing of Ti-6Al-4V components 被引量:6
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作者 ZHANG Pei-lei JIA Zhi-yuan +7 位作者 YAN Hua YU Zhi-shui WU Di SHI Hai-chuan WANG Fu-xin TIAN Ying-tao MA Song-yun LEI Wei-sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第4期1100-1110,共11页
Wire arc additive manufacturing(WAAM)is a novel manufacturing technique by which high strength metal components can be fabricated layer by layer using an electric arc as the heat source and metal wire as feedstock,and... Wire arc additive manufacturing(WAAM)is a novel manufacturing technique by which high strength metal components can be fabricated layer by layer using an electric arc as the heat source and metal wire as feedstock,and offers the potential to produce large dimensional structures at much higher build rate and minimum waste of raw material.In the present work,a cold metal transfer(CMT)based additive manufacturing was carried out and the effect of deposition rate on the microstructure and mechanical properties of WAAM Ti-6Al-4V components was investigated.The microstructure of WAAM components showed similar microstructural morphology in all deposition conditions.When the deposition rate increased from 1.63 to 2.23 kg/h,the ultimate tensile strength(UTS)decreased from 984.6 MPa to 899.2 MPa and the micro-hardness showed a scattered but clear decline trend. 展开更多
关键词 wire and arc additive manufacturing titanium alloys cold metal transfer deposition rate
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Dropwise condensation heat transfer enhancement on surfaces micro/nano structured by a two-step electrodeposition process 被引量:3
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作者 Hamid Reza TALESH BAHRAMI Alireza AZIZI Hamid SAFFARI 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第5期1065-1076,共12页
Condensation is an important regime of heat transfer which has wide applications in different industries such as power plants,heating,ventilating and air conditioning,and refrigeration.Condensation occurs in two diffe... Condensation is an important regime of heat transfer which has wide applications in different industries such as power plants,heating,ventilating and air conditioning,and refrigeration.Condensation occurs in two different modes including filmwise (FWC) and dropwise (DWC) condensation.DWC occurring on hydrophobic and superhydrophobic surfaces has a much higher heat transfer capacity than FWC.Therefore,wide investigations have been done to produce DWC in recent years.Superhydrophobic surfaces have micro/nano structures with low surface energy.In this study,a two-step electrodeposition process is used to produce micro/nano structures on copper specimens.The surface energy of specimens is reduced by a self-assembled monolayer using ethanol and 1-octadecanethiol solution.The results show that there is an optimum condition for electrodeposition parameters.For example,a surface prepared by 2000 s step time has 5 times greater heat transfer than FWC while a surface with 4000 s step time has nearly the same heat transfer as FWC.The surfaces of the fabricated specimens are examined using XRD and SEM analyses.The SEM analyses of the surfaces show that there are some micro-structures on the surfaces and the surface porosities are reduced by increasing the second step electrodeposition time. 展开更多
关键词 dropwise condensation heat transfer ELECTRODEPOSITION micro/nano structure POROSITY
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Economical Evaluation of a Low-Enthalpy Geothermal Resource Located in an Arid-Zone Area 被引量:1
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作者 Salah Masheitil Brian Agnew +1 位作者 Sara Walker Mosbah Talbi 《Journal of Energy and Power Engineering》 2012年第7期1013-1021,共9页
In this work an economical evaluation that established the viability of a low enthalpy geothermal resource as an energy source in north Africa is presented. The factors considered included the payback period, average ... In this work an economical evaluation that established the viability of a low enthalpy geothermal resource as an energy source in north Africa is presented. The factors considered included the payback period, average rate of return, net present value, and net benefit-cost ratio. The model was based on utilising the energy source to energise four models that comprised thermal equipment consisting of water/air cooled single/half effect lithium bromide water mixture absorption chillers and an R-245fa organic Rankine cycle. These modelled cycles were based on the energy demand for Waddan city a community in southern Libya which has a demand for combined cooling/electricity only or cooling/electricity with district hot water supply. The results revealed that all of the proposed simulated stand-alone models, except the water-cooled half effect chiller, are not economically viable unless they are heavily subsidized or combined with the district hot water supply at least in the winter season. 展开更多
关键词 Libya low-temperature geothermal resources economical analysis IPSEpro organic Rankine cycle absorption chillers.
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Cold Light Mirror Fabricated by Electr on Beam Evaporation of TiO_2 and SiO_2
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作者 ZHONGDi-sheng XUGuang-zhong 《Semiconductor Photonics and Technology》 CAS 2000年第1期59-64,共6页
A process suitable for production on a large scale of cold light mirror for film projector is introduced. Deposition parameters required for producing TiO 2/SiO 2 optical multilayer systems by electron beam evaporatio... A process suitable for production on a large scale of cold light mirror for film projector is introduced. Deposition parameters required for producing TiO 2/SiO 2 optical multilayer systems by electron beam evaporation of TiO 2 and SiO 2 starting materials are investigated. Manufacture and techniques of cold mirror and the adhesion,stability, wear and corrosion resistance of cold mirror by this process are discussed. The result shows that cold mirror produced has good optical properties and better adhesion. 展开更多
关键词 Cold light mirror Deposition process Optical coatings
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Ecological Responses to Holocene Millennial-Scale Climate Change at High Altitudes of East and Central Asia: A Case Study of Picea/Abies Pollen Changes in Lacustrine Sediments 被引量:2
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作者 LI Yu ZHANG Cheng-qi ZHOU Xue-hua 《Journal of Mountain Science》 SCIE CSCD 2014年第3期674-687,共14页
Ecosystem response to climate change in high-altitude regions is a focus on global change research. Picea/Abies forests are widely distributed at high altitudes of East and Central Asia, and their distribution changes... Ecosystem response to climate change in high-altitude regions is a focus on global change research. Picea/Abies forests are widely distributed at high altitudes of East and Central Asia, and their distribution changes are sensitive to climate change. Humidity is an important climatic factor that affects high-altitude ecosystems; however, the relationship between distribution changes of Picea/Abies forests and millennial-scale variability of humidity is still not dear. Palynological records can provide insights into millennial-scale paleovegetation changes, which have been successfully used to reconstruct past climate change in East and Central Asia. In this study, we synthesized 24 Picea/Abies pollen and humidity/moisture changes based upon Holocene lake records in East and Central Asia in order to explore the response of high-latitude ecosystem to millennial-scale climate change. The changing pattern of Holocene lacustrine Picea/Abies pollen in arid Central Asia differs from that of monsoonal East Asia, which can be due to different millennial-scale climate change patterns between monsoonal and arid Central Asia. Then, the relationship between changes in Picea/Abies pollen and humidity/moisture conditions was examined based on a comparison of pollen and humidity/moisture records. The results indicate that millennial-scale Picea/Abies distribution changes aremainly controlled by moisture variability at high altitudes, while the temperature effect plays a minor role in Picea/Abies distribution changes. Moreover, this research proves that lacustrine Picea/Abies pollen can be used as an indicator of millennial-scale humidity/moisture evolution at high altitudes in East and Central Asia. 展开更多
关键词 Lake sediments Palynological records High-altitude regions Picea/Abies Asian summermonsoon MILLENNIAL-SCALE Climate change
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Dynamic Analysis for Bose-Einstein Condensation in Quantum Cavity
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作者 ZHANGLi WANGCheng +1 位作者 LIYan-Min WANGJin-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期900-904,共5页
For the two-level atoms system interacting with single-mode active field in a quantum cavity, the dynamics of the Bose-Einstein Condensation (BEC) is analyzed using an ordinary method suggested by authors to solve the... For the two-level atoms system interacting with single-mode active field in a quantum cavity, the dynamics of the Bose-Einstein Condensation (BEC) is analyzed using an ordinary method suggested by authors to solve the system of Schrodinger representation in the Heisenberg representation. The wave function of the atoms is given. The stability factor determining the BEC and the selection rules of the quantum transition are solved. 展开更多
关键词 Bose-Einstein condensation quantum cavity REPRESENTATION laser cooling
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Viability of Extended Goat Semen Stored at Refrigerated Condition
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作者 Flocerfida Pagador Aquino Krystel Grace Vergara +1 位作者 Lerma Cajuigan Ocampo Eufrocina dela Pena Atabay 《Journal of Agricultural Science and Technology(A)》 2014年第2期169-176,共8页
Due to the small volume of goat semen ejaculate, just a few doses of goat semen were produced when the sperm concentration is 100 × 10^/mL. The study was aimed to determine the viability of extended goat semen at... Due to the small volume of goat semen ejaculate, just a few doses of goat semen were produced when the sperm concentration is 100 × 10^/mL. The study was aimed to determine the viability of extended goat semen at refrigerated condition at 5 ℃ using varying sperm concentrations and evaluated if sperm concentration lower than 100 × 10^6/mL would affect the motility, viability and sperm morphology at refrigerated condition. Using an artificial vagina, ejaculated goat semen was collected from goat semen donor aged 1.5 year. Physical evaluation of the collected semen showed an average volume of 0.54 mL, mean pH of 6.8 and a milky white color with thick consistency indicative of high concentration. Fresh goat semen had an initial average of 76% with an average initial sperm concentration of 128 × 10^/mL. The semen was divided into four treatments: sperm concentration of 100× 10^/mL, 75 × 10^/mL, 50 × 10^/mL and 25 × 10^/mL, and were stored at 5 ℃ for a period of 10 d. The semen evaluation was performed for each of the four treatments every other day. Results showed that the sperm concentration of spermatozoa affected the duration of storage based on the sperm motility percentage, viability and morphology of spermatozoa. The extended goat semen with sperm concentration of 25 and 50 million sperm/mL is optimal for storage within 6 d that gave satisfactory percentage motile, viable and morphologically normal spermatozoa. 展开更多
关键词 Extended semen goat semen ejaculate MOTILITY sperm concentration.
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PH_3 monitoring in Arctic and Dalian bay areas
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作者 封颖 Wang Qiang +1 位作者 Yao Ziwei Geng Jinju 《High Technology Letters》 EI CAS 2010年第4期437-440,共4页
In this paper, we use pre-column 2 times low-temperature cryo-trap enrichment--gas chromatography(GC) /nitrogen and phosphorus detector(NPD)to detect and analyze phosphine in Arctic pole area for the first time. T... In this paper, we use pre-column 2 times low-temperature cryo-trap enrichment--gas chromatography(GC) /nitrogen and phosphorus detector(NPD)to detect and analyze phosphine in Arctic pole area for the first time. The results show phosphine exists in all of the samples in Arctic pole biosphere and phosphine concentration in Arctic atmosphere is between 18.54- 132.18 ng/m^3, almost the same as that in Antarctic atmosphere; phosphine concentration in Dalian bay sea surface sediments is between 116. 8- 554.3 ng/kg, almost the same as that reported in Jiao-zhou bay. Our research of phosphine will shed new light on the mechanisms showing how the phosphorus supplement influences the biogeochemical cycle and global warming. 展开更多
关键词 PHOSPHINE Arctic pole area Dalian bay area distribution rules DETECT
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Numerical simulation on boiling heat transfer of evaporation cooling in a billet reheating furnace
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作者 冯明杰 王恩刚 +2 位作者 王海 李艳东 刘兵 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第6期1515-1524,共10页
The boiling heat transfer of evaporation cooling in a billet reheating furnace was simulated.The results indicate that the bubbles easily aggregate inside of the elbow and upper side of the horizontal regions in theπ... The boiling heat transfer of evaporation cooling in a billet reheating furnace was simulated.The results indicate that the bubbles easily aggregate inside of the elbow and upper side of the horizontal regions in theπshaped support tubes.The circulation velocity increasing helps to improve the uniformity of vapor distribution and decrease the difference of vapor volume fraction between upper and down at end of the horizontal sections.With the increase of circulation velocity,the resistance loss and the circulation ratio both increase,but the former will decrease with the increase of work pressure. 展开更多
关键词 FURNACE evaporation cooling subcooled flow boiling support tube two-fluid model
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Enhanced cold active lipase production by metagenomic library recombinant clone CALIP3 with a step-wise temperature and dissolved oxygen level control strategy
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作者 Zhuhua Chan Runping Wang +1 位作者 Fan Yang Runying Zeng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1263-1269,共7页
A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temp... A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temperature and dissolved oxygen(DO) on cold active lipase production by batch culture of metagenomic library recombinant clone(CAPL3) from deep-sea sediment were investigated. First, a two-stage temperature control strategy was developed, in which the temperature was kept at 34 ℃ for the first 15 h, and then switched to30 ℃. The cold active lipase activity and productivity reached 315.2 U·ml^-1and 8.08 U·ml^-1·h^-1, respectively,increased by both 14.5% compared to the results obtained with temperature controlled at 30℃. In addition, different DO control modes were conducted, based on the data obtained from the different DO control strategies and analysis of kinetics parameters at different DO levels. A step-wise temperature and DO control strategy were developed to improve lipase production, i.e., temperature and DO level were controlled at 34℃, 30% during 0–15 h;30 ℃, 30% during 15–18 h, and 30 ℃, 20% during 18–39 h. With this strategy, the maximum lipase activity reached 354.6 U·ml^-1at 39 h, which was 28.8% higher than that achieved without temperature and DO control(275.3 U·ml^-1). 展开更多
关键词 Deep-sea sediments Metagenomic library Cold active lipase Step-wise temperature and DO control strategy
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手卷创作必须强调对经典的坚守
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作者 秦健 《中国书法》 CSSCI 北大核心 2016年第3期112-112,共1页
谈到书法创作,我更喜欢创作横式作品或者竖式小品,因为一来宿舍桌子小,二来不想麻烦别人拉纸,这样可以随心所欲,再晚也没人打扰。我的作品风格基调是安静、稳定、淡然,以苏东坡、八大山人为基调的一批作品,好多同道看了会说太"平"了... 谈到书法创作,我更喜欢创作横式作品或者竖式小品,因为一来宿舍桌子小,二来不想麻烦别人拉纸,这样可以随心所欲,再晚也没人打扰。我的作品风格基调是安静、稳定、淡然,以苏东坡、八大山人为基调的一批作品,好多同道看了会说太"平"了。我原来只是一名教师,不善交游,少觥筹交错,每天晚上喜欢用上一摞毛边,安静的在灯光下度过,感受着经典碑帖给我带来的愉悦。 展开更多
关键词 作品风格 八大山人 竖式 横式 静美 大品 人我 作手 天对 冷积
原文传递
Chilling rather than photoperiod controls budburst for gymnosperm species in subtropical China 被引量:2
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作者 Yuan-Qi Pan Xiu Zeng +4 位作者 Wen-De Chen Xin-Ran Tang Kui Dai Yan-Jun Du Xi-Qiang Song 《Journal of Plant Ecology》 SCIE CSCD 2022年第1期100-110,共11页
The mechanisms regulating spring phenology have been extensively studied in angiosperm species.However,given that gymnosperms and angiosperms diverged 300 million years ago,phenology may be triggered by different cues... The mechanisms regulating spring phenology have been extensively studied in angiosperm species.However,given that gymnosperms and angiosperms diverged 300 million years ago,phenology may be triggered by different cues in gymnosperm species.The regulatory mechanisms of phenology in subtropical regions remain largely unknown.In combination,it remains untested whether subtropical gymnosperm species have chilling requirements and are photosensitive.We conducted a climate chamber experiment with three chilling and three photoperiod treatments to investigate budburst during an 8-week forcing period.We tested whether budburst of eight gymnosperms species(Cryptomeria japonica,Cunninghamia lanceolata,Cupressus funebris,Ginkgo biloba,Metasequoia glyptostroboides,Pinus massoniana,Pseudolarix amabilis and Podocarpus macrophyllus)was photoperiod sensitive or has strong chilling requirements and whether photoperiod or chilling was more important for advancing budburst.Chilling advanced budburst and increased the percentage of budburst for gymnosperm species.Gymnosperm species required moderate chilling days to advance budburst.Interestingly,the forcing requirement for gymnosperm species was higher than that for angiosperms in the same forest,suggesting that gymnosperms may need more cumulative forcing to initiate budburst than do angiosperms.Compared with temperate gymnosperm species in Germany(194-600℃days),the subtropical species studied here had a much higher forcing requirement(814-1150℃days).The effects of photoperiod were minor,suggesting that chilling outweighs photoperiod in advancing budburst of gymnosperm species in this subtropical region.These results reveal that increased winter temperatures with continued global warming may impact not only angiosperms but also gymnosperms,leading to their delayed spring budburst. 展开更多
关键词 chilling requirement climate change forcing requirement Gutianshan spring phenology twig cutting experiment
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Enhanced magnetocaloric performances and tunable martensitic transformation in Ni_(35)Co_(15)Mn_(35-x)Fe_(x)Ti_(15) all-d-metal Heusler alloys by chemical and physical pressures 被引量:1
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作者 Yong Li Liang Qin +1 位作者 Siyuan Huang Lingwei Li 《Science China Materials》 SCIE EI CAS CSCD 2022年第2期486-493,共8页
The solid-state magnetic cooling(MC)method based on the magnetocaloric effect(MCE)is recognized as an environmentally friendly and high-energy-efficiency technology.The search or design of suitable magnetic materials ... The solid-state magnetic cooling(MC)method based on the magnetocaloric effect(MCE)is recognized as an environmentally friendly and high-energy-efficiency technology.The search or design of suitable magnetic materials with large MCEs is one of the main targets at present.In this work,we apply the chemical and hydrostatic pressures in the Ni_(35)Co_(15)Mn_(35-x)Fe_(x)Ti_(15) all-d-metal Heusler alloys and systematically investigate their crystal structures,phases,and magnetocaloric performances experimentally and theoretically.All the alloys are found to crystallize in an ordered B2-type structure at room temperature and the atoms of Fe are confirmed to all occupy at sites Mn(B).The total magnetic moments decrease gradually with increasing Fe content and decreasing of volume as well.The martensitic transformation temperature decreases with the increase of Fe content,whereas increases with increasing hydrostatic pressure.Moreover,obviously enhanced magnetocaloric performances can also be obtained by applied pressures.The maximum values of magnetic entropy change and refrigeration capacity are as high as 15.61(24.20)J(kg K)^(−1) and 109.91(347.26)J kg^(−1) withΔH=20(50)kOe,respectively.These magnetocaloric performances are superior to most of the recently reported famous materials,indicating the potential application for active MC. 展开更多
关键词 magnetocaloric performances magnetic properties pressure effects magnetocaloric effect all-d-metal Heusler alloys
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