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Application Effect of Cassava Starch Anaerobic Fermentation Liquid on Watermelon Production
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作者 邓英毅 郑虚 +5 位作者 韦民政 张艺超 叶亦心 莫干辉 覃婵婵 屈啸 《Agricultural Science & Technology》 CAS 2017年第12期2557-2560,共4页
In order to find out a new way for environment-friendly and resourcelized utilization of cassava starch processing wastewater, the cassava starch anaerobic fermentation liquid was applied in watermelon production, and... In order to find out a new way for environment-friendly and resourcelized utilization of cassava starch processing wastewater, the cassava starch anaerobic fermentation liquid was applied in watermelon production, and its effects on the growth and development, yield and fruit quality of watermelon were investigated. The results showed that the cassava starch anaerobic fermentation liquid significant- ly promoted the vegetative and reproductive growth and improved the yield and fruit quality of watermelon. Compared with conventional fertilization, the application of cassava starch anaerobic fermentation both with COD concentration of 1 200 mg/L according to the amount of 150 t/hm2 promoted the growth of vines and leaves of watermelon plants, brought forward the flowering, fruiting and harvest of watermelon and significantly increased the fruit number, fruit weight, yield, fruit size, fruit shape index, soluble solid content, soluble sugar content, soluble protein content and Vita- min C content of watermelon. At the same time of improving the yield and quality of watermelon, cassava starch anaerobic fermentation liquid was turned into treasure as a liquid fertilizer. This study provides a new ideal for the yield and quality im- provement of watermelon and the wastewater treating of starch factories. 展开更多
关键词 Cassava starch anaerobic fermentation liquid WATERMELON production Vegetative growth YIELD QUALITY
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Extraction of Theanine from Waste Liquid of Tea Polyphenol Production in Aqueous Two-phase Systems with Cationic and Anionic Surfactants 被引量:8
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作者 张军伟 王艳 彭奇均 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期31-36,共6页
Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that ... Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that the region of ASTP is narrow and there is only a two-phase region of cationic surfactant. The increase in concentrations of NaBr and Na2SO4 are beneficial to the formation of ASTP. Theanine concentration in the bottom phase increases with increasing concentration of theanine, whereas the Partition coefficient and extraction rate only change a littlewhen the concentration of theanine is above 0.2 g.L-'. With the increase of SDS concentration, the phase ratio and the partition coefficient decrease, while the extraction efficiency of theanine increases and the concentration of theanine changes a little in the range from 2.4/7.5 to 2.8/7.2 for SDS/CTAB ratio. The temperature has a notable ef- fect on the concentration of theanine in the bottom phase, partition coefficient and extraction rate of theanine. The increase of waste liquid decreases the phase ratio, increases the concentration and extraction rate of theanine in the bottom ohase, since the orotein and the saccharide enter the bottom nhase with theanine. 展开更多
关键词 aqueous two-phase system SURFACTANT THEANINE waste liquid of tea polyphenol production EXTRACTION
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Study on Influencing Factors of Methane Production Efficiency of Microbial Electrolytic Cell with CO_(2) as Carbon Source
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作者 Qifen Li Yuanbo Hou +2 位作者 Yongwen Yang Liting Zhang Xiaoxiao Yan 《Journal of Renewable Materials》 EI 2023年第8期3333-3350,共18页
Reducing CO_(2) to produce methane through microbial electrolytic cell(MEC)is one of the important methods of CO_(2) resource utilization.In view of the problem of low methanogenesis rate and weak CO_(2) conversion ra... Reducing CO_(2) to produce methane through microbial electrolytic cell(MEC)is one of the important methods of CO_(2) resource utilization.In view of the problem of low methanogenesis rate and weak CO_(2) conversion rate in the reduction process,theflowfield environment of the cathode chamber is changed by changing the upper gas cir-culation rate and the lower liquid circulation rate of the cathode chamber to explore the impact on the reactor startup and operation and products.The results showed that under certain conditions,the CO_(2) consumption and methane production rate could be increased by changing the upper gas recirculation rate alone,but the increase effect was not obvious,but the by-product hydrogen production decreased significantly.Changing the lower liquid circulation rate alone can effectively promote the growth of biofilm,and change the properties of biofilm at the later stage of the experiment,with the peak current density increased by 16%;The methanogenic rate decreased from the peak value of 0.561 to 0.3 mmol/d,and the CO_(2) consumption did not change signifi-cantly,which indicated that CO_(2) was converted into other organic substances instead of methane.The data after coupling the upper gas circulation rate with the lower liquid circulation rate is similar to that of only changing the lower liquid circulation rate,but changing the upper gas circulation rate can alleviate the decline of methane pro-duction rate caused by the change of biofilm properties,which not only improves the current density,but also increases the methane production rate by 0.05 mmol/d in the stable period.This study can provide theoretical and technical support for the industrial application scenario offlowfield regulation intervention of microbial elec-trolytic cell methanogenesis. 展开更多
关键词 BIOMETHANATION microbial electrolytic cell gas circulation rate liquid circulation rate methane production
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Tuning the cross-linked structure of basic poly(ionic liquid)to develop an efficient catalyst for the conversion of vinyl carbonate to dimethyl carbonate
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作者 Zhaoyang Qi Shiquan Zhong +4 位作者 Huiyun Su Changshen Ye Limei Ren Ting Qiu Jie Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期106-116,共11页
Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium ... Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and methanol.However,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and recovery.To address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and functionalization.These poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic characteristics.Research was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing DMC.It was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant changes.The results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC. 展开更多
关键词 Poly(ionic liquid) Cross-linking degree Dimethyl carbonate production Transesterification reaction Mechanism
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Automatic Detection Instrument for the Ratio of Chlorine to Bromine in Oxidized Liquid of Bromine Production Based on Fuzzy Method
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作者 Yu Naigong Wang Kaiyan 《仪器仪表学报》 EI CAS CSCD 北大核心 2006年第z1期159-161,共3页
In the process of bromine production,because of lag adjustment methods,there are problems of adjusting delay,raw material wastage and low growth rate.By considering the nature of bromine production,with the help of fu... In the process of bromine production,because of lag adjustment methods,there are problems of adjusting delay,raw material wastage and low growth rate.By considering the nature of bromine production,with the help of fuzzy data processing method,computer detection and display technique,we designed an automatic detection instrument for the ratio of chlorine to bromine in oxidized liquid of bromine production.This instrument can be used to detect the different parameters of raw materials adjustment and control in real time,and afford assurance that raw materials will be adjusted in time.This paper briefly introduces the working mechanism,hardware and software design of the instrument. 展开更多
关键词 BROMINE production fuzzy relation list RATIO of CHLORINE to BROMINE in OXIDIZED liquid OXIDIZING electric potential automatic detection
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Adjustment of Liquid Production in Reservoir with Handling Capacity Constraints
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作者 Jie Tan Dong Zhang +2 位作者 Dongdong Yang Songru Mou Qin Peng 《Journal of Geoscience and Environment Protection》 2019年第4期18-25,共8页
A oilfield was an oil reservoir with strong bottom water in offshore, the water cut was as high as 96%. In the high water cut stage, the most effective way of increasing oil production was to extract liquid and increa... A oilfield was an oil reservoir with strong bottom water in offshore, the water cut was as high as 96%. In the high water cut stage, the most effective way of increasing oil production was to extract liquid and increase oil. The processing capacity of oilfield fluid was limited by the conditions. By using Petrel-RE-2017 software, combining reservoir engineering and percolation mechanics methods, this paper analyzes the effect of large-scale liquid pumping, expand coverage and shut-in coning in oil reservoirs with bottom water, and formulates the adjustment strategy of single well production structure of the whole oilfield. It was confirmed that large-scale liquid production can expand coverage and shutting down well can reduce water cut. It can provide reference and guidance for oil field with strong bottom water when it encounters bottleneck of liquid treatment capacity. 展开更多
关键词 Strong BOTTOM WATER RESERVOIR High WATER Cut liquid production Structure Adjustment MAXIMUM liquid production Capacity MAXIMUM Reasonable Pressure BOTTOM WATER Coning
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Enhancement of Shikonin Production in Cell Suspension Cultures of Arnebia Euchroma Employing Two-Liquid-Phase Systems
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作者 傅旭庆 吕德伟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1998年第1期90-94,共5页
1 INTRODUCTIONThe production of secondary metabolites using plant cells has been the subject of much inter-est in recent years.Despite that tremendous research efforts had been made in this topic,notmany products have... 1 INTRODUCTIONThe production of secondary metabolites using plant cells has been the subject of much inter-est in recent years.Despite that tremendous research efforts had been made in this topic,notmany products have reached the commercial stage.It is generally acknowledged that the mainproblem in this field is the lack of basic knowledge of the biosynthetic routes,and the mechanisms found to bring about the production of such secondary metabolites.There are,however,some techniques that have beneficial effects on the production and ex- 展开更多
关键词 Arnebia Euchroma SHIKONIN production TWO-liquid-PHASE SYSTEM
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Determination of Melamine in Animal Blood Products by High Performance Liquid Chromatography 被引量:1
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作者 YU Wei WU Wei-wei JIANG Guo-yong CHENG Guo-xiang 《Animal Husbandry and Feed Science》 CAS 2010年第6期20-21,25,共3页
[Objective] To investigate the optimal determination conditions of melamine in animal blood products by high performance liquid chromatography (HPLC). [ Method] The blood samples were extracted with ultrasonic in 1%... [Objective] To investigate the optimal determination conditions of melamine in animal blood products by high performance liquid chromatography (HPLC). [ Method] The blood samples were extracted with ultrasonic in 1% trichloroacetic acid (TDA) and acetonitrile. After purifying by solide phase extraction (SPE), the samples were analyzed by H PLC. r Result I The optimal conditions of HPLC were as follows: the chromatographic column was Zorbax SB-CS; the mobile phase was ion-pairs buffer-acetonitrile (95/5, V/V) ; the flow rate was 1.0 ml/min; the column temperature was 25 ℃ and the UV detection wavelength was 235 nm. The determined melamine concentration range was 0.001 -0.050 mg/ml; the linear correlation coefficient was 0.999 4; the concentration limit of melamine was 0.1 mg/kg; the average recovery rate of the melamine were 97.60% - 100.65%, and the relative standard deviation (RSD) was 1.23% -3.04%.[ Conclusion] The HPLC is simple, accurate and repeatable for determination of the melamine in animal blood products. 展开更多
关键词 High performance liquid chromatography MELAMINE Blood products
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Evaluation of Sweet Sorghum as a Feedstock by Multiple Harvests for Sustainable Bioenergy Production 被引量:1
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作者 Mingli Wang Zhanguo Xin +7 位作者 Brandon Tonnis Glenn Farrell David Pinnow Zhenbang Chen Jerry Davis Jianming Yu Yen-Con Hung Gary A. Pederson 《Journal of Sustainable Bioenergy Systems》 2012年第4期122-137,共16页
Sweet sorghum has become an important feedstock for bioethanol production. Total sugar yield and multiple harvests can directly affect ethanol production cost. Little is known about stem traits and multiple harvests t... Sweet sorghum has become an important feedstock for bioethanol production. Total sugar yield and multiple harvests can directly affect ethanol production cost. Little is known about stem traits and multiple harvests that contribute to sugar yield in sweet sorghum. Stem traits were evaluated from 25 sweet and grain sorghum accessions. Stems were harvested twice at the soft-dough stage and the stems were pressed with a hydraulic press. Sugars in the stem juice were quantified by high performance liquid chromatography. Sweet sorghum produced five times more fresh stem weight and dry stem mass (830 gand164 g) than grain sorghum (150 gand27g). Sweet sorghum produced a much higher volume of juice and higher yield of sugars (366 ml and42 g) per stem than grain sorghum (70 ml and4 g). Significant variability in fresh stem weight (72 - 1837 g), juice volume (31 - 753 ml), sugar yield (3 - 81 g), dry stem mass (14 - 383 g), and sugar yield/dry stem mass ratio (0.11 - 0.53) per stem was detected among sweet sorghum accessions. Stem sugar yield was significantly correlated with stem fresh weight and juice volume. Sorghum was harvested twice within one growing season resulting in some sweet sorghum accessions producing double amount of sugars. Sweet sorghum produced three times more dry mass weight (bagasse) than fermentable sugar weight. To reduce feedstock cost, methods have to be developed for efficiently utilizing bagasse. Our results showed high fresh stem weight, high ratio of sugar yield to dry stem mass, and double harvests are prime traits to boost sugar yield. Sweet sorghum may be suitable for multiple harvests in certain regions of theU.S.TheU.S.sweet sorghum collection needs to be screened for acces- sions that can be harvested twice with an extended feedstock-production season and used as a feedstock for sustainable and renewable bioenergy production. 展开更多
关键词 Sorghum Fresh STEM Weight Juice Volume Sugar Yield Dry STEM Mass Hydraulic Press (HP) High Performance liquid Chromatography (HPLC) MULTIPLE Harvest BAGASSE SUSTAINABLE BIOENERGY production
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Fast Pyrolysis of Biomass in a Spout-fluidized Bed Reactor ——Analysis of Composition and Combustion Characteristics of Liquid Product from Biomass 被引量:2
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作者 陈明强 王君 +4 位作者 王新运 张学才 张素平 任铮伟 颜涌捷 《过程工程学报》 EI CAS CSCD 北大核心 2006年第2期192-196,共5页
关键词 生物量 热解 流动床 液体产物 燃烧特征
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Study on Production Regulation of Reservoir under Different Demand
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作者 Jie Tan Enhui Sun +2 位作者 Wei Wang Jingmin Guo Wei Yang 《Journal of Power and Energy Engineering》 2019年第7期39-49,共11页
Natural gas production is related to the demand for gas, which is low in summer and high in winter. While the gas storage is still being demonstrated and constructed, oil and gas fields should formulate and implement ... Natural gas production is related to the demand for gas, which is low in summer and high in winter. While the gas storage is still being demonstrated and constructed, oil and gas fields should formulate and implement production control schemes suitable for gas reservoirs. The realization of natural gas production can not only meet the demand of gas consumption, but also ensure the scientific and efficient development of gas reservoirs, and meet the needs of dynamic analysis of gas reservoirs at different development stages and scientific research of gas reservoirs. In this paper, KAPPA Workstation 5.20 software is used to determine the inflow dynamic model of a single well. The nodal method is used to determine the reasonable production and peak shaving capacity in combination with the critical fluid carrying capacity of gas wells and the erosion rate of gas wells. The reasonable production allocation in each period, i.e. the production control scheme, is obtained. It solves the scientific and efficient development of natural gas in X gas field, which is still under the construction of gas storage, and provides guidance for gas reservoir development management and regulation. 展开更多
关键词 GAS RESERVOIR Regulation of production EROSION Velocity The Critical liquid Carrying Capacity of GAS Well REASONABLE production
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Novel closed-cycle reaction mode for totally green production of Cu_(1.8)Se nanoparticles based on laser-generated Se colloidal solution
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作者 Zhangyu Gu Yisong Fan +7 位作者 Yixing Ye Yunyu Cai Jun Liu Shouliang Wu Pengfei Li Junhua Hu Changhao Liang Yao Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期41-48,共8页
Non-stoichiometric copper selenide(Cu_(2-x)Se,x=0.18~0.25)nanomaterials have attracted extensive attentions due to their excellent thermoelectric,optoelectronic and photocatalytic performances.However,efficient produc... Non-stoichiometric copper selenide(Cu_(2-x)Se,x=0.18~0.25)nanomaterials have attracted extensive attentions due to their excellent thermoelectric,optoelectronic and photocatalytic performances.However,efficient production of Cu_(2-x)Se nanoparticles(NPs)through a green and convenient way is still hindered by the inevitable non-environmentally friendly operations in common chemical synthesis.Herein,we initially reveal the coexistence of seleninic acid content and elemental selenium(Se)NPs in pulsed laser-generated Se colloidal solution.Consequently,we put forward firstly a closedcycle reaction mode for totally green production of Cu_(1.8)Se NPs to exclude traditional requirements of high temperature and toxic precursors by using Se colloidal solution.In such closed-cycle reaction,seleninic acid works as the initiator to oxidize copper sheet to release cuprous ions which can catalyze the disproportion of Se NPs to form Se O_(3)^(2-)and Se^(2-)ions and further produce Cu_(2-x)Se NPs,and the by-product SeO_(3)^(2-)ions promote subsequent formation of cuprous from the excessive Cu sheet.In experiments,the adequate copper(Cu)sheet was simply dipped into such Se colloidal solution at 70℃,and then the stream of Cu_(1.8)SeNPs could be produced until the exhaustion of selenium source.The conversion rate of Se element reaches to more than 75%when the size of Se NPs in weakly acidic colloidal solution is limited between 1 nm and 50 nm.The laser irradiation duration shows negative correlation with the size of Se NPs and unobvious impact to the p H of the solution which both are essential to the high yield of Cu_(1.8)SeNPs.Before Cu sheet is exhausted,Se colloidal solution can be successively added without influences to the product quality and the Se conversion rate.Such green methodology positively showcases a brand-new and potential strategy for mass production of Cu_(2-x)Se nanomaterials. 展开更多
关键词 non-stoichiometric copper selenide green production selenium colloidal solution laser irradiation in liquids
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Auto-optimization of production-injection rate for reservoirs with strong natural aquifer at ultra-high water cut stage
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作者 LEI Zhanxiang MU Longxin +4 位作者 ZHAO Hui LIU Jian CHEN Heping JIA Fenshu ZHOU Zhanzong 《Petroleum Exploration and Development》 2019年第4期804-809,共6页
Based on the optimal control theory and taking the production law of reservoirs with strong natural aquifer as the basic constraint, a mathematical model of liquid production for such reservoirs in the later stage of ... Based on the optimal control theory and taking the production law of reservoirs with strong natural aquifer as the basic constraint, a mathematical model of liquid production for such reservoirs in the later stage of development is established. The model is solved by improved simultaneous perturbation stochastic approximation algorithm(SPSA), and an automatic optimization software for liquid production is developed. This model avoids the disadvantage of traditional optimization methods that only focus on the maximum value of mathematics but ignore the production law of oilfield. It has the advantages of high efficiency of calculation, short period and automatic optimization. It can satisfy the automatic optimization of liquid production in later stage of oilfield development. The software was applied in the oilfield development of D oilfield, Ecuador in South America, and realized the automatic optimization of liquid production in the later stage of oilfield development. 展开更多
关键词 reservoir with STRONG NATURAL AQUIFER liquid production OPTIMIZATION optimal control theory SPSA algorithm South AMERICA Ecuador
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Studying Cu Alloy Corrosion Products in Cooling Liquid
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作者 A.A .El-Meligi National Research Centre, Physical Chem. Dept., Dokki, Cairo, Egypt 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第5期507-510,共4页
The effect of cooling liquid used for heat exchangers on the Cu alloy corrosion products has been examined using potential-time measurements under applied current condition (anodizing), potentiodynamic polarization, X... The effect of cooling liquid used for heat exchangers on the Cu alloy corrosion products has been examined using potential-time measurements under applied current condition (anodizing), potentiodynamic polarization, X-ray diffraction (XRD) and infrared spectroscopy (IR) The corrosion products formed on the Cu alloy surface during anodizing, are Cu2O, Cu2(OH)3Cl, and Cu2S. NaCl is detected in the corrosion products. The film formation depends on the applied current and the shift of potential to nobler direction indicates its formation progress. 展开更多
关键词 CU Studying Cu Alloy Corrosion products in Cooling liquid
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LIQUID PRODUCTS MARINE TERMINAL OP-V OF KARACHI PORT,PAKISTAN WAS COMMISSIONED
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《中国远洋航务》 1995年第5期42-42,共1页
The Karachi Port of Pakistan is a deep natural sea port with a history of 150 years. The Port has an 11 km long approach channel decaracted with buoys for proriding safe navigation of 75,000 DWT tankers,modern contain... The Karachi Port of Pakistan is a deep natural sea port with a history of 150 years. The Port has an 11 km long approach channel decaracted with buoys for proriding safe navigation of 75,000 DWT tankers,modern container vessels,bulk Karachi Port is the premier port of Pakistan and handles over 85 percent of the whole dry gen- 展开更多
关键词 OP WAS liquid productS MARINE TERMINAL OP-V OF KARACHI PORT PAKISTAN WAS COMMISSIONED DWT
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The Effects of Microwave Pretreatment of Dairy Manure on Methane Production
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作者 Ian Chan Asha Srinivasan +4 位作者 Ping H. Liao Kwang V. Lo Donald S. Mavinic Jim Atwater James R. Thompson 《Natural Resources》 2013年第3期246-256,共11页
This study was undertaken to evaluate the efficiency of a liquid-solids separation process and microwave pretreatment, as well as anaerobic biodegradability of microwave pretreated dairy manure. Liquid-solids separati... This study was undertaken to evaluate the efficiency of a liquid-solids separation process and microwave pretreatment, as well as anaerobic biodegradability of microwave pretreated dairy manure. Liquid-solids separation of raw dairy manure resulted in solid and liquid fractions having different properties, with the solid fractions richer in total and volatile solids content and liquid fractions richer in nutrients and metal ions. Substantial amounts of soluble chemical oxygen demand and nutrients were released into the solution after the microwave treatment. The microwave pretreated dairy manure was also subjected to anaerobic digestion. The kinetic parameters of methane production potential, maximum methane production rate and lag time were determined using the modified Gompertz equation. Anaerobic digestion of liquid manure, without microwave treatment, outperformed the sets with microwave treatment. The microwave-treated liquid dairy manure, without acid addition had better results in terms of methane potential and methane production, than with acid addition. Thermophilic digestion exhibited a higher maximum methane production rate than that of mesophilic digestion, but lower methane yields. The microwave pretreatment of dairy manure resulted in high soluble chemical oxygen demand;however, methane yield was not increased. 展开更多
关键词 liquid-Solids SEPARATION MICROWAVE Treatment ANAEROBIC DIGESTION METHANE production
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Dairy Farming Conditions and Utilization Levels of Liquid Brewers’ Yeast in Kenya
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作者 Peter Alphonce Obuong Alaru Alfred Anakalo Shitandi +1 位作者 Symon Maina Mahungu John Muasya Kilumba Muia 《Open Journal of Animal Sciences》 CAS 2023年第1期1-19,共19页
Dairy production plays an integral part in supporting smallholder farmers’ livelihoods. The desire to increase the number of dairy cattle is not feasible due to the reduced output of feed resources occasioned by clim... Dairy production plays an integral part in supporting smallholder farmers’ livelihoods. The desire to increase the number of dairy cattle is not feasible due to the reduced output of feed resources occasioned by climate change. Consequently, the need to increase productivity per cow is inevitable. Conventional protein supplements are costly;hence, the need to explore affordable nutrientdense alternative feed resources. Liquid brewers’ yeast (LBY), a by-product of the brewing industry, is a rich protein supplement in dairy production. This study aimed to assess the dairy farming conditions and utilization levels of LBY as a feed supplement in Githunguri Sub-county, Kiambu. Semi-structured questionnaires were administered to 457 dairy farmers in a cross-sectional survey. The findings revealed that most farmers (94.2%) fed their cattle on established forage/fodder and crop residues with supplementation. Even though 53.1% of the respondents were aware of the use of LBY, only 30.6% utilized it to supplement dairy cows, most of whom (96.0%) used it fresh without preservation. Membership in farmers’ organizations increased awareness of LBY (r = 0.732). Principal component analysis indicated that the benefits of using LBY outweigh the challenges involved with a loading matrix of 0.891 - 0.954 and 0.681 - 0.807, respectively. The low adoption and use levels of LBY as a source of protein supplements were due to low awareness. There is a need for concerted efforts by stakeholders in the industry to increase farmers’ knowledge base on the utilization and effectiveness of LBY in dairy production. 展开更多
关键词 Dairy-production liquid Brewers’ Yeast PROTEIN SUPPLEMENT
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改良QuEChERS技术结合超高效液相色谱-串联质谱法测定水产品中扑草净及其代谢物残留 被引量:1
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作者 彭婕 穆迎春 +4 位作者 喻亚丽 陈建武 刘婷 何力 甘金华 《食品科学》 EI CAS CSCD 北大核心 2024年第3期185-192,共8页
采用改良QuEChERS技术作为前处理方法,建立了水产品中扑草净及其代谢物残留的超高效液相色谱-串联质谱分析方法。样品用乙腈提取,经增强型脂质去除吸附剂与Cleanert LipoNo组合净化,采用选择反应监测正离子模式测定,内标法定量。结果表... 采用改良QuEChERS技术作为前处理方法,建立了水产品中扑草净及其代谢物残留的超高效液相色谱-串联质谱分析方法。样品用乙腈提取,经增强型脂质去除吸附剂与Cleanert LipoNo组合净化,采用选择反应监测正离子模式测定,内标法定量。结果表明:扑草净及其代谢物在1.0~500 ng/mL质量浓度范围内线性关系良好,确定系数R2大于0.992,方法检出限和定量限分别低至0.20μg/kg和0.50μg/kg,在草鱼、克氏原螯虾和中华绒螯蟹等基质的加标实验中呈现良好的准确度与精密度,平均加标回收率和相对标准偏差分别为74.4%~113.7%和3.17%~11.47%。经内标法校正,5种扑草净及其代谢物在不同水产品中的基质效应不明显。方法实现了水产品中扑草净及其代谢物的识别与定量分析,并通过检测药浴扑草净的克氏原螯虾阳性样品验证了方法的适用性。 展开更多
关键词 超高效液相色谱-串联质谱 水产品 扑草净 代谢物 QUECHERS
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煤层气储层气-液-固多相渗流规律研究 被引量:1
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作者 韩文龙 李勇 +1 位作者 王延斌 赵石虎 《煤矿安全》 CAS 北大核心 2024年第7期22-30,共9页
揭示储层非饱和流阶段煤粉运移产出规律,对煤层气高效排采具有重要现实意义。基于气-液-固三相流模拟装置,通过设定不同煤粉粒径、注入流速、裂缝宽度和煤粉质量分数等条件,开展了煤层气储层非饱和流阶段煤粉产出运移特征试验,并分析了... 揭示储层非饱和流阶段煤粉运移产出规律,对煤层气高效排采具有重要现实意义。基于气-液-固三相流模拟装置,通过设定不同煤粉粒径、注入流速、裂缝宽度和煤粉质量分数等条件,开展了煤层气储层非饱和流阶段煤粉产出运移特征试验,并分析了煤粉沉淀量、产出量及煤岩气相与液相渗透率变化特征。研究表明:随着裂缝宽度增加,煤粉产出量呈现出逐渐增大的趋势,沉淀量呈现出先增大后减小的变化特征,在裂缝宽度为0.1 mm时达到最大值;随着煤粉质量分数的增大,产出量表现为先增大后减小(峰值点在0.15‰附近),沉淀量逐渐增大,说明煤粉在储层中运移存在一定的单位体积含量极值,超过极值后,煤粉将大量沉淀并堵塞孔裂隙;合理控制煤层气产水产气速率,能够有效地控制煤粉的产出,煤粉沉淀量和产出量随着注入流速的增长均呈现出先增大后减小的趋势,注入流速为5.0 mL/min时的煤粉沉积量最大,在流速为7.5 mL/min时煤粉产出量相对较高;液相渗透率演化特征呈现出逐渐降低和先稳定后逐渐降低2种变化趋势,气相渗透率演化特征较为复杂;综合注入压力、煤岩渗透率变化、煤粉产出和沉淀特征,可将煤粉在裂缝中运移划分为缓慢沉积、快速沉积和完全堵塞3个阶段。 展开更多
关键词 煤层气储层 气-液-固三相流 煤粉产出 煤粉运移 渗透率
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天然气井多相流强化携液理论及排液采气关键技术
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作者 白博峰 田伟 +7 位作者 赵昆鹏 贾友亮 李丽 杨旭东 赵峥延 李旭日 沈志昊 刘磊 《西安交通大学学报》 EI CAS CSCD 北大核心 2024年第5期10-18,共9页
天然气田稳产是保障我国能源安全的重大需求,气井积液是制约稳产的瓶颈,排液采气是保障稳产的关键。我国60%气井因积液年均产气量递减23%以上,且积液井数以年均5%的速率快速递增。由于对气井多相流动特性认识不足,传统排液采气技术仅适... 天然气田稳产是保障我国能源安全的重大需求,气井积液是制约稳产的瓶颈,排液采气是保障稳产的关键。我国60%气井因积液年均产气量递减23%以上,且积液井数以年均5%的速率快速递增。由于对气井多相流动特性认识不足,传统排液采气技术仅适用于积液轻微的浅直井且排液率较低。研究团队近年来聚焦天然气井排液采气难题,构建了基于气液流动结构调控的强化携液理论,突破了经典临界流速携液理论仅适用于环雾状流的局限;发明了抗油耐矿化度泡沫排液、复杂井筒速度管柱排液、超声速喷嘴雾化排液、气举柱塞接力举升排液等适用气井不同积液状态的高效低成本排液采气系列关键技术。研究成果已推广至长庆气田、中外合作开发区等11个气区,累计应用近12000口气井,占我国积液气井总数的30%以上。 展开更多
关键词 多相流动 强化携液 排液采气 气田稳产 能源安全
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