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Changes in the Activities of C4 Pathway Enzymes and Stable Carbon Isotope Discrimination in Flag Leaves of Super High-yield Hybrid Rice
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作者 阳成伟 林桂珠 +2 位作者 彭长连 陈贻竹 欧志英 《Acta Botanica Sinica》 CSCD 2003年第11期1261-1265,共5页
Activities of several key enzymes of C-4 photosynthesis pathway and stable carbon isotope discrimination were investigated in flag leaves of a super high-yield hybrid rice (Oryza sativa L.) cv. Peiai 64S/E32 and a tra... Activities of several key enzymes of C-4 photosynthesis pathway and stable carbon isotope discrimination were investigated in flag leaves of a super high-yield hybrid rice (Oryza sativa L.) cv. Peiai 64S/E32 and a traditional hybrid rice cv. Shanyou 63 at different developing stages. Results show that the activity of PEP carboxylase (PEPCase) increased with age of flag leave; the activity of NADP-malate dehydrogenase (NADP-MDH) increased and reached to a peak value at grain filling stage (68-75 d after transplanting), then fell down; the activity of NADP-MDH in cv. Peiai 64S/E32 was much higher than that in cv. Shanyou 63. Before ripening stage (95 d after transplanting), NADP-malic enzyme activity rose gradually. The level of stable carbon isotope discrimination (Delta(13)C) in flag leaves and grains at different developing stages were similar and exhibited a comparative high value at ripening stage. The average Delta(13)C in leaf of cv. Peiai 64S/E32 during different developing stages was 0.43parts per thousand more than that in cv. Shanyou 63. 展开更多
关键词 super high-yield hybrid rice C-4 photosynthesis pathway enzyme stable carbon isotope flag leaf
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Compensatory growth in hybrid tilapia (Oreochromis mossambicus×O. niloticus) reared in seawater, following restricted feeding 被引量:2
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作者 王岩 崔奕波 +1 位作者 杨云霞 蔡发盛 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第4期414-420,共7页
Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body... Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks, and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls. Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved digestibility, feed efficiency, or protein and energy retention efficiency. 展开更多
关键词 hybrid tilapia compensatory growth feed restriction ration level
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Study on Modification of Ultra-Stable Zeolite Prepared by Hydrothermal Method 被引量:2
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作者 Zhang Weilin Zhou Lingping +4 位作者 Shen Shimin Li Zheng Zhu Yuxia Tian Huiping Long Jun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2007年第2期55-59,共5页
The ultra-stable zeolite DASY-0.0 was prepared by hydrothermal method in commercial scale. Its structure was further modified via the treatment for cleaning of pores (CP). The zeolite samples before and after CP tre... The ultra-stable zeolite DASY-0.0 was prepared by hydrothermal method in commercial scale. Its structure was further modified via the treatment for cleaning of pores (CP). The zeolite samples before and after CP treating were analyzed and characterized by XRF, XRD, NMR, IR, BET and DTA. The results showed that, in comparison with the conventional ultra-stable zeolite DASY-0.0 prepared by the hydrothermal process, the CP-modified zeolite SOY0 exhibited a higher relative crystallinity, a larger surface area and pore volume, a higher thermal stability and contained less amorohous non-framework A1. 展开更多
关键词 ZEOLITE ultra-stable MODIFICATION thermal stability
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Sex Determination Mechanisms in Fish 被引量:2
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作者 ZHANG Quanqi SUN Xiaohua QI Jie WANG Zhigang WANG Xinglian WANG Xubo ZHAI Teng 《Journal of Ocean University of China》 SCIE CAS 2009年第2期155-160,共6页
In fish,sex determination(SD) system shows high variation. The SD mechanisms include environmental and genetic regulation. The research on SD system and related genes in intensively studied fish species was reviewed. ... In fish,sex determination(SD) system shows high variation. The SD mechanisms include environmental and genetic regulation. The research on SD system and related genes in intensively studied fish species was reviewed. Although some genes have been described as sex-related,only DMRT1bY can be considered as a master sex determination gene and none of them has been utilized in aquaculture. The variation of fish SD system,the importance of sex-related genes in evolution research and the relations between environmental factors and sex-related genes were also discussed. The fish sex determination mechanism remains largely unknown. Further research needs to be done considering the significance of fish SD studies in basic and applied aspects. 展开更多
关键词 sex determination environmental factors sex-related gene FISH
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Flow-Based Iodometric Extraction Method by the Hollow Fiber Membrane for the Determination of Selenium Sulfide Levels in Cosmeceutical Products 被引量:1
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作者 Suprawee Wongsuchoto Slra Nltlyanontaklt Pakom Varanusupaku 《Journal of Chemistry and Chemical Engineering》 2012年第4期299-306,共8页
A flow-based iodometric extraction method for the determination of selenium sulfide was developed and applied to cosmeceutical products. Iodine which was generated from the reduction of selenium(IV) ions by iodide i... A flow-based iodometric extraction method for the determination of selenium sulfide was developed and applied to cosmeceutical products. Iodine which was generated from the reduction of selenium(IV) ions by iodide ion was on-line extracted using a polypropylene HFM (hollow fiber membrane) liquid extraction technique. The HFM extraction unit was constructed and used to support an organic solvent (hexane) and separate between the organic phase and aqueous phase. The resulting purple extract was carried to a fiber optic spectrophotometric detector for the measurement at 521 nm. Parameters which affected the extraction efficiency, sensitivity and sample throughput such as iodide (selenium molar ratio, extraction time and washing time between the cycles) were investigated and optimized. A linear dynamic range of 80-373 mg.Lt selenium solution was obtained with an extraction time of 60 sec. The total analysis time including washing was about 180 sec which provided a sample throughput of approximately 20 samples'hr1 and excluded the sample pre-treatment. The recoveries for the determination of selenium in the forms of selenium dioxide and selenium sulfide were in the range of 103%-104% with 1%-3% RSD (relative standard deviation). The relative errors of this method which was applied for determination of selenium sulfide levels in an anti-dandruff shampoo and a cosmeceutical bead sample were both less than 2.5%. 展开更多
关键词 Flow-based method IODOMETRY selenium sulfide hollow fiber membrane cosmeceutical products.
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A Way to Decrease the Negative Impact of Aquaculture on other Marine Inhabitants
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作者 Delik Dokkovich Gabaev 《Journal of Environmental Science and Engineering(A)》 2017年第12期606-612,共7页
Spat collectors deployed at sea, in addition to the target species, attract also many larvae of accompanying species, which die after transplanting the cultivated one into cages. However, these juveniles often have a ... Spat collectors deployed at sea, in addition to the target species, attract also many larvae of accompanying species, which die after transplanting the cultivated one into cages. However, these juveniles often have a higher value than the cultivated species, and their mortality is caused by smaller sizes. These are: red king crab, Japanese sea cucumber, sea urchins, Japanese cucumaria and several species of ascidians and sponges. However, the use of a realized niche, rather than a fundamental one, in selecting the area and depth to install collectors, and also improvement of their design, make it possible to cultivate a target species without reseeding to other constructions. This not only facilitates the cultivation process, but also increases the survival rate of the cultivated and accompanying species, since at the bottom, they reach either marketable or viable size in comfortable conditions. 展开更多
关键词 Collector-cage Patinopecten (Mizuhopecten) yessoensis Apostichopus japonicus Paralithodes camtschaticus Scapharca broughtoni
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Determination of Air/Fuel and Steam/Fuel Ratio for Coal Gasification Process to Produce Synthesis Gas
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作者 A. Gungor M. Ozbayoglu +2 位作者 C. Kasnakoglu A. Biyikoglu B.Z. Uysal 《Journal of Environmental Science and Engineering》 2011年第6期799-804,共6页
In this study, a coal gasification model is developed based on nine simultaneous reactions. For given gasification temperature and pressure, the air/fuel and water vapor/fuel ratio are optimized for maximum H2/CO rati... In this study, a coal gasification model is developed based on nine simultaneous reactions. For given gasification temperature and pressure, the air/fuel and water vapor/fuel ratio are optimized for maximum H2/CO ratio by parametric study. Furthermore, the cold gas efficiency and higher heating value of the synthesis gas produced are computed for each case. Optimum locations of investigated parameters are also searched for maximizing cold gas efficiency and higher heating value of the synthesis gas. 展开更多
关键词 Coal gasification production of synthesis gas parametric study optimization.
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Microbial Assessment of Used Drilling Mud and Mix Cement Fluid for Production Well
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作者 Abdulmohsen Al-Humam Mohammed Sindi Abdullah Al-Wadei 《Journal of Physical Science and Application》 2017年第3期41-43,共3页
Drilling fluids and mud additives are generally acknowledged as potential sources of contamination in deep drilling programs, as they may contain high concentration of nutrients for subsurface microorganisms. Microorg... Drilling fluids and mud additives are generally acknowledged as potential sources of contamination in deep drilling programs, as they may contain high concentration of nutrients for subsurface microorganisms. Microorganisms introduced into drilling process cause a number of problems that can lead to significant costs for the industry. Numerous studies have shown that biogenic sulfide production in oil and natural gas fields have led to a number of problems, including reservoir plugging, reservoir souring, reduced product quality, and corrosion of metal-containing equipment. The aim of this study is to determine the microbial contamination of water drilling mud and cement Mix fluid at two Saudi Aramco well SA-10 & SA-12 and to adequately perform microbial assessment for the well both wells. Microbiological analyses were conducted to evaluate the level of contamination by TB (total bacterial) and SRB (sulfate reducing bacteria) using and q-PCR (quantitative poly chain reaction) technique. Microbial results for SA-10 indicated that total bacteria were 2.21 × 103/mL for mix fluid sample and 1.22 × 105/mL for drilling water sample. In addition, microbial results for total SRB were 1.65 × 102/mL and 1.34 × 102 mL, respectively. Moreover, microbial results for SA-12 indicated 5.89 × 105/mL of total bacteria and 98/mL of SRB in the sample. 展开更多
关键词 SRB drilling mud mix fluid bacteria contamination.
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Determination of Moisture Sorption Isotherm Characteristics of Dehydrated Sorghum Flour ("Ogi")
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作者 Ajiboye Solomon Oyerinde 《Journal of Agricultural Science and Technology(B)》 2013年第2期86-91,共6页
Dehydrated sorghum flour ("ogi") is useful as additional ingredient in certain food and pharmaceutical formulation, this could be obtained by soaking sorghum in water for 3 to 4 days, wet milling the soaked materi... Dehydrated sorghum flour ("ogi") is useful as additional ingredient in certain food and pharmaceutical formulation, this could be obtained by soaking sorghum in water for 3 to 4 days, wet milling the soaked material, and fermentation for another 3 to 4 days. Typically, the fermented product is boiled into a pap or cooked into a stiff porridge. However, the fermented product can not be easily handled or stored and does not have a long shelf life (typically less than a week). Dehydrating the fermented product into flour is one of the ways that is being employed to overcome these problems. Equilibrium moisture content (EMC) of dehydrated sorghum flour (aka "ogi") was therefore determined at two temperatures of 25℃ and 40℃ and four salt solutions. Zinc chloride (ZnCl2), potassium acetate (KC2H3O2), calcium chloride (CaCl2) and sodium chloride (NaCl) salts were prepared to correspond to equilibrium relative humidities of 10.0% to 75.4%. The moisture sorption characteristics of the sorghum product showed the characteristics S-shaped sorption isotherm curve that is typically obtained for agricultural products. The equilibrium data and the monomolccular layer moisture content values were estimated using the Brunauer-Emmett-Teller (BET) equation. The moisture content range for optimum storage of the dehydrated sorghum flour lies between 2.84% to 3.69% at 25℃ and 6.84% and 7.67% at 40℃. The information obtained from this study will help in the design and selection of storage and packaging systems for dehydrated sorghum flour. 展开更多
关键词 Moisture adsorption sorghum flour equilibrium moisture content moisture isotherm storage stability
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Stability Study on Hydroelectric Production Site Using Eigenvalues Analysis Method
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作者 Pedro Camilo de Oliveira e Silva Basile Kawkabani +3 位作者 Sébastien Alligné Christophe Nicolet Jean-Jacques Simond Francois Avellan 《Journal of Energy and Power Engineering》 2012年第6期940-948,共9页
The eigenvalues analysis method is generally applied to synchronous machines by using d, q-components. This paper presents the application of this method on an equivalent model for the synchronous machine based on pha... The eigenvalues analysis method is generally applied to synchronous machines by using d, q-components. This paper presents the application of this method on an equivalent model for the synchronous machine based on phase variables a, b, c instead of d, q-components. The advantages of this approach, essential for programs using phase variables as state variables, are presented. The application of this method to a complete hydroelectric production site including hydraulic components (pump-turbine, penstock, gallery, reservoir...) permits the study and analysis of the interactions between the hydraulic, electric and regulation parts of the system. Results coming from the proposed eigenvalues analysis method and the numerical simulations confirm the interest of the presented approach. 展开更多
关键词 Hydraulic systems eigenvalues and eigenfunctions power systems transient analysis.
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Determination of Pesticides Residues in Some Fruits and Vegetables Imported to Iraq
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作者 Ismael Ibrahim Alyaseri Mukhtar Abdul Sattar Ali Abdul Karim Jawad Ali Nadir Kamil Bahi 《Journal of Agricultural Science and Technology(A)》 2012年第1期65-70,共6页
A study was carried out in the laboratories of the National Center for Pesticides Control/State Board for Plant Protection / Ministry of Agriculture in 2010-2011. The aim was to determine the residues of some pesticid... A study was carried out in the laboratories of the National Center for Pesticides Control/State Board for Plant Protection / Ministry of Agriculture in 2010-2011. The aim was to determine the residues of some pesticides in fruits and vegetables imported to Iraq from neighboring countries (Jordan, Syria, Turkey and Iran). Two types of fruits (apples and oranges) and two types of vegetables (tomatoes and cucumber) were selected for the purpose of this study. These fruits and vegetables are the most agricultural products imported for human consumption in Iraq. Samples were taken from different border points and from local markets. Extraction, clean up and analysis were then processed. The results indicated the presence of small amounts of residues of certain pesticides such as Deltamethrin and Abamectin and Thiamethoxam in some samples. However, these amounts were less than the limit allowed internationally. No indication was observed for the presence of other pesticides residues such as Bifenthrin Trticonazol and Imidacloprid ... etc. in the samples analyzed. Therefore, there is a need to continuity of inspection on pesticides residues in agricultural products imported to Iraq in order to prevent the entry of contaminating materials and secure human safety. 展开更多
关键词 Pesticides residues VEGETABLES FRUITS Iraq
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Growth Profile of Gilthead Bream Reared in Mega Flow Re-circulating Aquaculture System
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作者 Mohammad Al-Zibdah 《Journal of Agricultural Science and Technology(A)》 2014年第4期307-314,共8页
This study was designed to compare the effect of two exchange rates (ERs; 0.5 m^3 feed/kg and 1.5 m^3 feed/kg) in re-circulating aquaculture systems (RAS) on water quality and fish growth profiles on fish stocks ... This study was designed to compare the effect of two exchange rates (ERs; 0.5 m^3 feed/kg and 1.5 m^3 feed/kg) in re-circulating aquaculture systems (RAS) on water quality and fish growth profiles on fish stocks (200 indiv/m^3 of 251.4 g e 20.67 g) of gilthead bream, Sparus aurata. Water quality, fish growth, specific growth rate (SGR) and feed conversion ratio under the two ERs were examined for a period of six months. Inorganic nutrient in RAS, temperature, dissolved oxygen and pH were measured daily. Feeding regime effect was also determined on the fish quality and organoleptic characteristics and thus opts to energy optimization of the system. The fish reared under the 1.5 m^3 feed/kg ER demonstrate enhanced growth, the daily SGR and the conversion ratio. Sensory test analysis revealed differences in the organoleptic characteristics between the two experimental fish stocks with considerably high acceptance scores for fish reared at high ER. Nutrient concentrations: ammonia, nitrate, nitrite and phosphate were lower in RAS of the highest ER when compared to those reared under the 0.5 m3/kg feed. Results suggest an ER of 1.5 m^3 feed/kg improved both fish quality and growth profile of the gilthead bream. 展开更多
关键词 RAS gilthead sea bream ER GROWTH conversion rate.
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Utilizing of Methane from Polish Hard Coal Mines
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作者 Justyna Swolkien 《Journal of Energy and Power Engineering》 2015年第2期149-160,共12页
The methane capturing and its utilization is of great importance for the safety in Polish coal mines. The present study deals with methods which are used to capture and utilize it in hard coal mines. It is of great im... The methane capturing and its utilization is of great importance for the safety in Polish coal mines. The present study deals with methods which are used to capture and utilize it in hard coal mines. It is of great importance to know that at present, ethane recovered in operating mines is obtained only through drainage systems whose implementation is enforced by health and safety regulations. Because of the fact that the amount of methane released in hard coal mines is expected to rise in years to come, as the methane content of coal seams increases with depth, heavy emphasis should be placed on methane recovery and the practical applications of the captured gas. If mine gas was officially recognised as a primary source for producing "environmentally friendly electricity", would open the perspectives of increasing methane utilization. In addition, the mining industry would gain an incentive to intensify methane recovery. It would be possible to carry out additional work focused on methane drainage from excavations which are not operated. Also, the costs of methane drainage could be included in the costs of energy production, which would undoubtedly have a positive effect on the profitability of mining companies. 展开更多
关键词 Hard coal mines methane utilization methane hazard methane emission.
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Voluntary Carbon Market in Turkey
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作者 Fehiman Ciner Aydemir Akyurek 《Journal of Energy and Power Engineering》 2014年第11期1908-1912,共5页
Nowadays, global warming is a major environmental concern. Climate change is dominating the environmental agendas, especially in developed countries at first, but by now, around the world. Several initiatives have bee... Nowadays, global warming is a major environmental concern. Climate change is dominating the environmental agendas, especially in developed countries at first, but by now, around the world. Several initiatives have been undertaken to reduce the effect of increasing atmospheric GHGs (greenhouse gasses) concentrations. Emerging carbon emissions trade under the Kyoto Protocol serves to market the carbon quotas among the countries, thus, it helps to increase their level of GNP (gross national product). Emissions trade is being performed in the voluntary and compliant markets. Increasing interest in emission trade emerged carbon and energy exchanges markets in the world. Turkey is located in the voluntary markets, and organizations buying carbon offset credits in order to achieve their voluntary emission reduction goals. GS (gold standard) and VCS (verified carbon standard) are mainly being used to finance renewable energy projects in Turkey. In the GS, there are 209 projects which are currently in the approval process or in the application, such as wind energy, hydroelectric power plant and biogas energy production. In addition to these, in the VCS, there are 61 projects which are mainly energy industries, in the approval process or in the application. Most environmental issues require long-term plans which include international cooperation, especially climate change. The Kyoto Protocol marks the beginning of a new era to combat global climate change. Voluntary markets are very popular and forty percent of the total global GS projects and around nine percent of VCS projects are implemented in Turkey. These projects are initial steps for future implementations of compliant markets in Turkey. 展开更多
关键词 Kyoto protocol carbon markets voluntary carbon trade greenhouse gas Turkey.
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四川:微生态制剂高效养水产
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《农村养殖技术》 2012年第8期55-55,共1页
四川通威集团生产的通威微生态制剂是目前我国水产行业内科技含量高、增值大的高科技产品,低投入和高产出率。作为中国水产饲料龙头企业,全国几十万养殖户正广泛使用通威股份微生态制剂实现增产增收,致富奔小康。微生态制剂是根据微... 四川通威集团生产的通威微生态制剂是目前我国水产行业内科技含量高、增值大的高科技产品,低投入和高产出率。作为中国水产饲料龙头企业,全国几十万养殖户正广泛使用通威股份微生态制剂实现增产增收,致富奔小康。微生态制剂是根据微生态理论,在微生态学理论指导下,用正常微生物,经特殊工艺制成的含有活菌或包含细菌菌体及其代谢产物的主要用于动物的活菌制剂。 展开更多
关键词 四川 微生态制剂 高效养殖技术 水产定 饲料
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pyrG is required for maintaining stable cellular uracil level and normal sporulation pattern under excess uracil stress in Aspergillus nidulans 被引量:1
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作者 SUN XianYun ZHU JuFen +5 位作者 BAO Li HU ChengCheng JIN Cheng HARRIS Steven D. LIU HongWei LI ShaoJie 《Science China(Life Sciences)》 SCIE CAS 2013年第5期467-475,共9页
Tight control of the intracellular uracil level is believed to be important to reduce the occurrence of uracil incorporation into DNA. The pyrG gene ofAspergillus niduIans encodes orotidine 5'-phosphate decarboxylase... Tight control of the intracellular uracil level is believed to be important to reduce the occurrence of uracil incorporation into DNA. The pyrG gene ofAspergillus niduIans encodes orotidine 5'-phosphate decarboxylase, which catalyzes the conversion of orotidine monophosphate (OMP) to uridine monophosphate (UMP). In this study, we found that pyrG is critical for maintaining uracil at a low concentration in A. nidulans cells in the presence of exogenous uracil. Excess uracil and its derivatives had a stronger inhibitory effect on the growth of the pyrG89 mutant with defective OMP decarboxylase activity than on the growth of wild type, and induced sexual development in the pyrG89 mutant but not in wild type. Analysis of transcriptomic responses to excess uracil by digital gene expression profiling (DGE) revealed that genes related to sexual development were transcrip- tionally activated in the pyrG89 mutant but not in wild type. Quantitative analysis by HPLC showed that the cellular uracil level was 6.5 times higher in the pyrG89 mutant than in wild type in the presence of exogenous uracil. This study not only provides new information on uracil recycling and adaptation to excess uracil but also reveals the potential effects of OMP decarboxylase on fungal growth and development. 展开更多
关键词 orotidine 5'-phosphate decarboxylase STRESS URACIL sexual development
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