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挤压膨化对大米和糙米理化与营养特性的影响 被引量:34
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作者 马永轩 张名位 +8 位作者 魏振承 张雁 张瑞芬 邓媛元 刘磊 唐小俊 肖娟 黄菲 董丽红 《食品研究与开发》 CAS 北大核心 2017年第12期9-12,共4页
以大米和糙米为原料,分析比较了大米和糙米挤压膨化前后理化和营养特性的变化。结果表明,大米和糙米挤压膨化后其水溶性指数和吸水性指数显著提高,大米分别提高了13.9倍1.32倍,糙米分别提高了5.4倍1.45倍,而其Carr指数和Hausner比显著降... 以大米和糙米为原料,分析比较了大米和糙米挤压膨化前后理化和营养特性的变化。结果表明,大米和糙米挤压膨化后其水溶性指数和吸水性指数显著提高,大米分别提高了13.9倍1.32倍,糙米分别提高了5.4倍1.45倍,而其Carr指数和Hausner比显著降低,大米分别降低了14.93%和5.6%,糙米分别降低了39.14%和20.83%。脂肪含量显著减少,蛋白质含量没有显著性的变化,还原糖和糊化度显著的增加,大米分别增加了6.68倍和46.73%,而糙米分别增加了11倍和72.97%。同时,挤压膨化降低了米粉的亮度,使其颜色变黄。总的膳食纤维和不溶性膳食纤维降低,可溶性膳食纤维的含量增加。 展开更多
关键词 挤压膨化 大米 糙米 理化 营养
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酱油制曲过程中理化、生化指标动态变化 被引量:11
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作者 黄持都 鲁绯 +2 位作者 袁圆 纪凤娣 程永强 《中国酿造》 CAS 北大核心 2010年第5期38-41,共4页
制曲是酱油酿造过程中一个非常重要的工序,菌种、制曲温度、制曲时间等都是影响制曲的重要因素。通过对制曲过程进行监控,研究测定分析了制曲不同阶段曲料的理化指标和生化指标的变化情况,为行业内的相关研究、特别是在优化制曲工艺条... 制曲是酱油酿造过程中一个非常重要的工序,菌种、制曲温度、制曲时间等都是影响制曲的重要因素。通过对制曲过程进行监控,研究测定分析了制曲不同阶段曲料的理化指标和生化指标的变化情况,为行业内的相关研究、特别是在优化制曲工艺条件方面提供参考。 展开更多
关键词 酱油 制曲 理化 酶活 动态变化
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Role of nickel on vanadium poisoned FCC catalyst: A study of physiochemical properties 被引量:6
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作者 U.J.Etim B.Xu +3 位作者 P.Bai Rooh Ullah F.Subhan Z.Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第4期667-676,共10页
Active sites of Fluid catalytic cracking (FCC) catalyst are poisoned during operation in the FCC reactor due to causes including feedstock contaminant metals deposition. This leads to activity, selectivity and increas... Active sites of Fluid catalytic cracking (FCC) catalyst are poisoned during operation in the FCC reactor due to causes including feedstock contaminant metals deposition. This leads to activity, selectivity and increasing coking problems, thereby raising concern to the refiner. This work investigated effect of nickel coexisting with vanadium in the FCC feedstock on the standard FCC catalyst during cracking process, in which destruction of active sites occurs as a result of the metals deposition. Laboratory simulated equilibrium catalysts (E-cats) were studied by XRD, FTIR spectroscopy, N-2 adsorption, solid state MAS-NMR, SEM and H-2-TPR. Results revealed that vanadium, above a certain concentration in the catalyst, under hydrothermal conditions, is highly detrimental to the catalyst's structure and activity. Conversely, nickel hardly affects the catalyst structure, but its co-presence in the catalyst reduces destructive effects of vanadium. The mechanism of nickel inhibition of vanadium poisoning of the catalyst is discussed. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 展开更多
关键词 FCC catalyst Contaminant metals ACTIVITY physiochemical properties Mechanism
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Post Impact of Hydrocarbon Spillage on Physicochemical Parameters and Heavy Metals in the Santa Barbara River, Nembe, Bayelsa State
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作者 Amararu Onyema Isukul Godwin Jeremiah Udom Richmond Uwanemesor Ideozu 《International Journal of Geosciences》 2023年第10期935-954,共20页
The work of the paper focused on the post impact of oil spill contamination of groundwater in Bassambiri Nembe Bayelsa State. Groundwater samples were sampled from hand dug wells from eight stations including the cont... The work of the paper focused on the post impact of oil spill contamination of groundwater in Bassambiri Nembe Bayelsa State. Groundwater samples were sampled from hand dug wells from eight stations including the control point for physico-chemical investigation using sterilized glass bottles. Sampling was carried out upstream and downstream on the Santa Barbara River across the stations and the results are as follows surface water pH ranged 6.90 - 7.50, electrical conductivity 19739.41 μS/cm - 28920.64 μS/cm and Chloride 6019.63 - 9274.82 mg/l. The Total Dissolved Solids (TDS) varied from 10472.72 mg/l - 16538.19 mg/l dissolved oxygen (DO) 6.21 mg/l - 7.371 mg/l while the mean biochemical oxygen demand (BOD) 0.09 ± 0.52 mg/l - 2.4 ± 0.81 mg/l, temperature 28.04℃ - 31.79℃ while total alkalinity is 43.95 mg/L -73.87 mg/L. Calcium ion ranged 375.68 mg/l - 536.72 mg/l, Magnesium ion 88.35 - 243.24 mg/l and Potassium ion 41.27 - 121.17 mg/l. The results of the study showed that the pH, salinity, alkalinity, total suspended solids (TSS), Chlorides, Phosphates, and Nitrates are within permissible limits of the WHO, however the electrical conductivity, TDS, turbidity, DO, BOD, and hardness exceeded WHO permissible limits for drinking water. Total Petroleum Hydrocarbon (TPH) and Heavy metals had low concentrations in the Santa Barbara River across the study area suggesting that surface water is not polluted. However, the surfactants used initially to contain the oil pollution were effective based on this research. 展开更多
关键词 Post Impact Oil Spillage physiochemical Parameters Santa Barbara
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Effect on Optical and Antibacterial Activity of SnO2 and CuO Blended SnO2 Nanoparticles
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作者 Suresh Gopal Baskaran Iruson +2 位作者 Sathyaseelan Balaraman Senthilnathan Krishnmoorthy Manikandan Elayaperumal 《Soft Nanoscience Letters》 CAS 2023年第2期1-12,共12页
Nanocrystalline SnO<sub>2</sub> and CuO doped with SnO<sub>2</sub> were prepared by the co-precipitation method and characterized for different physiochemical properties and microbiological act... Nanocrystalline SnO<sub>2</sub> and CuO doped with SnO<sub>2</sub> were prepared by the co-precipitation method and characterized for different physiochemical properties and microbiological activity. The composition and morphological formation were characterized by XRD, HRTEM, Raman, FTIR, and UV-vis spectroscopy. The Powder X-ray analysis reveals that Sn4+ ions have substituted the Cu<sup>2+</sup> ions without changing the monoclinic structure of SnO<sub>2</sub> but the average particle size of the SnO<sub>2</sub> and CuO doped SnO<sub>2</sub> samples from 11 and 5 nm respectively. However, it exhibits an inhibiting strong bacterial growth against tested bacterial strains. 展开更多
关键词 SnO2 CuO Doped SnO2 physiochemical Properties Microbiological Activity
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Systematic Biological Upgrade of a Urea Fertilizer Effluent Treatment Plant Using GPS
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作者 Isyaku Ahmad Joseph T. Akintola +3 位作者 Regina J. Patinvoh Wilson F. Ekpotu Martins C. Obialor Philemon Chukwuebuka Udom 《Open Journal of Applied Sciences》 2023年第8期1457-1477,共21页
The use of modeling and simulation has developed into a critical tool for the sustainable management of wastewater, especially when it comes to replicating the complex biochemical procedures required for fertilizer ef... The use of modeling and simulation has developed into a critical tool for the sustainable management of wastewater, especially when it comes to replicating the complex biochemical procedures required for fertilizer effluent treatment, which calls for a significant amount of wastewater-related data. The biological improvement of a urea fertilizer effluent via GPS* simulation was carried out in this work using a methodical process. Using established analytical techniques, temperature, total suspended solids (TSS), biochemical oxygen demand (BOD), total phosphorus (T/), chemical oxygen demand (COD), total nitrogen (TN), total nitrate (NO<sub>3</sub>), electric conductivity (EC), turbidity, residual chlorine, urea, NH<sub>3</sub>, and heavy metals (Cu, Cd, Cr, Pb, Ni, and Fe) were assessed. The research revealed that the measured values from the fertilizer factory outfall effluent had high concentrations of all the physicochemical water quality indicators, with the exception of TSS, PO<sub>4</sub><sup>-</sup>, SO<sub>4</sub><sup>-</sup>, and NO<sub>3</sub><sup>-</sup>. These concentrations are higher compared to the authorized limits or suggested values by the Federal Environmental Protection Agency (FEPA). To improve the therapy biologically, however, a modeling and simulation program (GPS-X, version 8.0) was used with the physicochemical information gathered from the studied sample. The results of the treated water simulation showed that the concentrations of BOD<sub>5</sub> and COD had been significantly reduced by 35% and 44%, respectively. Additionally, it was discovered that total phosphorus (TP), nitrate (N), and total nitrogen (TN) were all within the permitted FEPA limit. The results revealed good treatment performance of the wastewater with increasing concentration of acetic acid and sodium hydroxide. Hence, the results of this research work identify the need for proper treatment of fertilizer industry effluents prior to their release into the environment. 展开更多
关键词 Fertilizer Wastewater Effluent Discharge Basin Outfall Basin physiochemical Analysis GPS* Modelling & Simulation
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Coconut oil research:Past,present,and future directions
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作者 Jiao-Jiao Yin He Huang +6 位作者 Xiao-Ming Jiang Xing-Yang Guo Bao-Hui Pan Pan Gao Wu Zhong Chuan-Rong Hu Dong-Ping He 《Food and Health》 2024年第1期43-52,共10页
Coconut oil contains a rich amount of medium-chain fatty acids,including lauric acid,decanoic acid,and octanoic acid,as well as the corresponding medium-chain triglycerides.It possesses functional attributes such as f... Coconut oil contains a rich amount of medium-chain fatty acids,including lauric acid,decanoic acid,and octanoic acid,as well as the corresponding medium-chain triglycerides.It possesses functional attributes such as facile digestion and absorption,as well as antibacterial and antioxidant properties.The study utilized the Citespace and VOSviewer visual analysis software to examine the quantity of published papers,authors,publishing institutions,research hotspots and frontiers of 3442 effective literatures on the theme of"coconut oil"in the Web of Science(WoS)Core Collection database.The research on coconut oil can be condensed into four primary sections:(1)investigation and utilization of physiochemical characteristics of coconut oil,(2)analysis of nutritional composition and study of the effectiveness of coconut oil,(3)identification of adulteration in coconut oil,(4)evaluation of the impact of coconut oil as a dietary supplement on animal metabolism.Additionally,research focal points have evolved in three distinct phases.Prior to 2008,numerous studies were conducted to investigate the precise fatty acid makeup of coconut oil and its potential for lowering cholesterol levels.From 2009 to 2016,significant emphasis was placed on examining the impact of coconut oil on methane production in ruminants.Between 2018 to 2023,the main focus will be on investigating how nanoparticles can alter the properties of coconut oil.In the future,the anticipated research areas of interest are expected to focus on the rapid detection method of coconut oil,the efficacy of coconut oil and the advancement of coconut resources.The objective of this review is to provide researchers with relevant information about coconut oil,aiming to foster the continued growth of the coconut oil industry. 展开更多
关键词 coconut oil visualized analysis research hotspots physiochemical properties nutrient composition
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Evaluation of soil nutrient status in poplar forest soil by soil nutrient systematic approach 被引量:5
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作者 余常兵 陈防 +1 位作者 罗治建 陈卫文 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期298-300,共3页
A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in lab... A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in laboratory through collection soil samples of study site. Ten treatments of application different fertilizers were designed such as CK, optimum treatment (N, P, K, Zn), N(P, K, Zn), P(N, K, Zn), K(N, P, Zn), +Mg(N, P, K, Zn, Mg), Zn (N,P,K), +2P(N, 2P, K, Zn), +2K(N, P, 2K, Zn), and 2N+2P+2K(2N, 2P, 2K, Zn) for field experiment to test the effect on tree height, diameter (DBH) growth, and dry weight of poplar. The results showed that there was no significant difference in tree heights between treatments with different fertilizers, diameter growth of poplar trees in treatments of lack of N and Zn was significantly slower than that of trees in optimum treatment, and dry weight of poplar dropped significantly for treatment of CK as well as treatments without application N and Zn. It is concluded that N and Zn were main limiting factor for poplar growth. Results from laboratory analysis and field experiment were uniform per-fectly, which proved that SNSA was reliable in evaluating soil nutrient status of poplar plantation. 展开更多
关键词 Soil nutrient status Soil Nutrient Systematic Approach Poplar plantation Limiting factor Evaluation method Soil physiochemical properties
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Physiochemical Properties of Resistant Starch and Its Enhancement Approaches in Rice 被引量:4
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作者 Ding Yi Wang Maike +3 位作者 Shen Yi Shu Xiaoli Wu Dianxing Song Wenjian 《Rice science》 SCIE CSCD 2021年第1期31-42,共12页
With changes in food preferences and life styles,more and more attentions have been focused on healthier food.Nowadays,resistant starch(RS)which can resist digestion in the human intestine has been recognized and acce... With changes in food preferences and life styles,more and more attentions have been focused on healthier food.Nowadays,resistant starch(RS)which can resist digestion in the human intestine has been recognized and accepted.High RS diet shows great benefit for the human health,and breeding high RS rice variety is a great target for realizing dietary intervention.To provide guidance for RS improvement in rice,this review summarized the unique physiochemical properties of RS and the possible approaches,i.e.genetic regulation,for enhancing RS content in rice,and proposed the potential ways to obtain rice variety with high RS content. 展开更多
关键词 RICE resistant starch starch modification physiochemical property
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超高压处理对法兰克福香肠理化及感官品质的影响 被引量:4
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作者 王洋 高杨 +2 位作者 戴瑞彤 郑海涛 李平兰 《肉类研究》 2012年第8期1-5,共5页
为探讨超高压处理对法兰克福香肠理化及感官品质的影响,采用200MPa(5、10min),400MPa(5、10min)和600MPa(5、10min)对真空包装法兰克福香肠进行二次杀菌处理。连续监测样品冷藏过程中pH值、挥发性盐基氮(TVB-N)、脂肪氧化(TBA-RS)、质... 为探讨超高压处理对法兰克福香肠理化及感官品质的影响,采用200MPa(5、10min),400MPa(5、10min)和600MPa(5、10min)对真空包装法兰克福香肠进行二次杀菌处理。连续监测样品冷藏过程中pH值、挥发性盐基氮(TVB-N)、脂肪氧化(TBA-RS)、质构、色泽和感官品质的变化。结果表明:超高压处理可以减缓法兰克福香肠保藏过程中pH值的降低,挥发性盐基氮的生成,但会增加脂肪氧化程度;另外会提高亮度,降低红度;降低硬度,增加内聚力;延缓感官品质的下降。 展开更多
关键词 超高压 真空包装 法兰克福香肠 理化 感官
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Formulation and Antioxidant Activity Evaluation of Theaflavin Effervescent Tablet
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作者 Wenjing QI Xueying WANG +4 位作者 Zhiling HU Qi ZHENG Qiyuan MAO Shiming LI Chang LIU 《Agricultural Biotechnology》 CAS 2023年第2期142-147,共6页
Theaflavins(TFs),as the major polyphenolic components of fermented tea,possess beneficial effects on human health.In this study,the effervescent tablets based on theaflavins were developed.The optimal formulation of T... Theaflavins(TFs),as the major polyphenolic components of fermented tea,possess beneficial effects on human health.In this study,the effervescent tablets based on theaflavins were developed.The optimal formulation of TF effervescent tablets was obtained by response surface methodology with the Box-Behnken design.Then,the physiochemical properties were evaluated,including hardness,friability,effervescent time and pH of the solution.At last,the antioxidant ability of TF effervescent tablets was studied through DPPH and ABTS radical scavenging assay.According to the results,the optimal formulation of the tablets contained TF powder 9.09%,disintegrating agent 43.80%(the weight ratio of citric acid and sodium bicarbonate was 1:1),aspartame 1.86%,PEG-6003%,and mannitol in balance.With the wet granulation method,the TF effervescent tablets displayed suitable hardness,fast disintegration time,good color,pleasant taste and high antioxidant activity.This study demonstrated that the TF effervescent tablets could be a valuable product for the supplement market and contribute to promoting practical application of TFs. 展开更多
关键词 THEAFLAVINS Effervescent tablet FORMULATION physiochemical property Antioxidant ability
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Modification on Synthesis of Mixed Ligand Chelates by Using Di- and Trivalent Transition Metal Ions with Schiff Base as Primary Ligand 被引量:1
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作者 Abdussalam Ali Maihub Faten Suliman Alassbaly +1 位作者 Marei Mailoud El-Ajaily Abdunnaser Mohamed Etorki 《Green and Sustainable Chemistry》 2014年第3期103-110,共8页
New mixed ligand chelates synthesized from di-and trivalent metal ions (Cr, Co, Ni, and Cu ions) and Schiff base (L1) resulted from the condensation of 4-dimethylaminobenzaldehyde with 2-aminophenol as primary ligand,... New mixed ligand chelates synthesized from di-and trivalent metal ions (Cr, Co, Ni, and Cu ions) and Schiff base (L1) resulted from the condensation of 4-dimethylaminobenzaldehyde with 2-aminophenol as primary ligand, whereas 2-nitroaniline (L2) represents the secondary ligand in a molar ratio of M:L1:L2 [1:1:1]. The synthesized Schiff base and chelates have been characterized by using several tools, such as, elemental analysis, molar conductivity, magnetic moment measurements, infrared and electronic spectra. The mass spectra of the ligands and Ni(II) chelate were used to justify the process of modification, as well as, the electron paramagnetic resonance spectrum which was carried out for Cu(II) chelate all in order to elucidate the chemical and geometrical structure of the chelates. On the basis of the obtained data, the geometry of the products was proposed for all the chelates. 展开更多
关键词 SCHIFF Base 2-Nitroaniline CHELATES 4-Dimethylaminobenzaaldehyde 2-AMINOPHENOL physiochemical Techniques
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Long-Term No-Tillage Direct Seeding Mode for Water-Saving and Drought-Resistance Rice Production in Rice-Rapeseed Rotation System 被引量:1
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作者 DU Xing-bin CHEN Chen +4 位作者 LUO Li-jun XIA Long-ping LIU Kang CHEN Yin-hua YU Xin-qiao 《Rice science》 SCIE 2014年第4期210-216,共7页
To study the effects of long-term no-tillage direct seeding mode on rice yield and the soil physiochemical property in a rice-rapeseed rotation system, a comparative experiment with a water-saving and drought-resistan... To study the effects of long-term no-tillage direct seeding mode on rice yield and the soil physiochemical property in a rice-rapeseed rotation system, a comparative experiment with a water-saving and drought-resistance rice (WDR) variety and a double low rapeseed variety as materials was conducted under no-tillage direct seeding (NTDS) mode and conventional tillage direct seeding (CTDS) mode for four years, using the CTDS mode as the control. Compared with the CTDS mode, the actual rice yield of WDR decreased by 8.10% at the first year, whereas the plant height, spikelet number per panicle, spikelet fertility, 1000-grain weight, grain yield, actual yield, and harvest index increased with no-tillage years, which led to the actual yield increase by 6.49% at the fourth year. Correlation analysis showed that the panicle length was significantly related to the actual yield of WDR. Compared with the CTDS mode in terms of the soil properties, the pH value of the NTDS mode decreased every year, whereas the contents of soil organic matter and total N of the NTDS mode increased. In the 0-5 cm layer of the NTDS mode, the soil bulk decreased, whereas the contents of soil organic matter, total N, and available N increased. In the 5-20 cm layer of the NTDS mode, the available N and K decreased, whereas the soil bulk, contents of soil organic matter, and total N increased. In summary, the NTDS mode increased the rice yield, and could improve the paddy soil fertility of the top layer. 展开更多
关键词 no-tillage direct seeding rice yield soil physiochemical property water-saving and drought-resistance rice rotation system
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Microscopic evaluation and physiochemical analysis of Dillenia indica leaf 被引量:1
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作者 S Kumar V Kumar Om Prakash 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第5期337-340,共4页
Objective:To study detail microscopic evaluation and physiochemical analysis of Dillenia indica(D.indica)leaf.Methods:Fresh leaf sample and dried power of the leaf were studied macroscopically and microscopically.Prel... Objective:To study detail microscopic evaluation and physiochemical analysis of Dillenia indica(D.indica)leaf.Methods:Fresh leaf sample and dried power of the leaf were studied macroscopically and microscopically.Preliminary phytochemical investigation of plant material was done.Other WHO recommended parameters for standardizations were also performed.Results:The detail microscopy revealed the presence of anomocytic stomata,unicellular trichome,xylem fibres,calcium oxalate crystals,vascular bundles,etc.Leaf constants such as stomatal number,stomatal index,vein-islet number and veinlet termination numbers were also measured.Physiochemical parameters such as ash values,loss on drying,extractive values,percentage of foreign matters,swelling index,etc.were also determined.Preliminary phytochemical screening showed the presence of steroids,terpenoids,glycosides,fatty acids,flavonoids,phenolic compounds and carbohydrates.Conclusions:The microscopic and physiochemical analysis of the D.indica leaf is useful in standardization for quality,purity and sample identification. 展开更多
关键词 Dillenia INDICA Fibre LEAF constant MICROSCOPY physiochemical STOMATA XYLEM
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The Role of Biochar to Enhance Anaerobic Digestion: A Review 被引量:3
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作者 Shuai Tang Zixin Wang +2 位作者 Zhidan Liu Yuanhui Zhang Buchun Si 《Journal of Renewable Materials》 SCIE EI 2020年第9期1033-1052,共20页
Biochar,one of the products of thermochemical conversion of biomass,possesses specific physiochemical properties such as conductivity,pore adsorption,surface functional groups,and cation exchange capacity.Anaerobic di... Biochar,one of the products of thermochemical conversion of biomass,possesses specific physiochemical properties such as conductivity,pore adsorption,surface functional groups,and cation exchange capacity.Anaerobic digestion(AD)as a classical bio-wastes conversion technology,suffers from inhibitions,process instability,and methanogenic inefficiency which limit its efficiency.With the advantages of pH buffering,functional microbes enrichment,inhibitors alleviating,and direct interspecies electron transfer(DIET)accelerating,biochar suggests a promising application as additives for AD.Herein,this paper reviewed the noting physicochemical properties of biochar,and discussed its roles and related mechanisms in AD.Further,this paper highlighted the advantages and drawbacks,and pointed out the corresponding challenges and prospects for future research and application of biochar amending AD. 展开更多
关键词 BIOCHAR physiochemical properties anaerobic digestion methane production MECHANISMS
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环氧交联牛颈静脉带瓣管道的形态学和理化性能的研究
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作者 徐朝军 胡铁辉 +5 位作者 吴忠仕 胡建国 冯耀光 马忠厦 王晖 胡剑 《中国现代医学杂志》 CAS CSCD 北大核心 2005年第18期2767-2769,2772,共4页
目的探讨环氧化合物交联牛颈静脉带瓣管道的外观形态,组织稳定性及流体物理性能的特征。方法取新鲜牛颈静脉带瓣管道24根,随机分为环氧化合物处理组(PC组,n=8),戊二醛处理组(GA组,n=8)及新鲜对照组(Control组,n=8)。分别测量各组处理前... 目的探讨环氧化合物交联牛颈静脉带瓣管道的外观形态,组织稳定性及流体物理性能的特征。方法取新鲜牛颈静脉带瓣管道24根,随机分为环氧化合物处理组(PC组,n=8),戊二醛处理组(GA组,n=8)及新鲜对照组(Control组,n=8)。分别测量各组处理前后管壁厚度,管腔外径及瓣膜的抗返流性能的变化。测定处理前后各组的组织含水量,热皱缩温度,组织断裂强度,断裂伸长率。结果PC组外观形态,管腔外径,瓣膜抗返流性能较对照组差异无显著性(P>0.05),GA组血管变硬,呈淡黄色,抗返流性能下降,与PC组相比差异有显著性(P<0.05)。PC组及GA组的组织含水量和断裂伸长率均低于Control组(P<0.05),PC组和GA组的热皱缩温度,断裂强度较Control组均升高(P<0.05);PC组组织断裂强度GA组比较差异无显著性。结论环氧化合物能有效交联牛颈静脉带瓣管道提高其组织的稳定性,且能较好的保护瓣膜的抗返流性能。 展开更多
关键词 颈静脉 环氧化合物 形态学 理化性能
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Water Quality Index of Waste Stabilisation Ponds and Downstream of Discharge Point
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作者 Obenne Pearl Gopolang Moatlhodi Wise Letshwenyo 《Journal of Environmental Protection》 2019年第8期993-1005,共13页
Water quality index has been used in various researches for the assessment of water quality for various uses and discharges into the environment. The purpose of this study was to determine the water quality index of t... Water quality index has been used in various researches for the assessment of water quality for various uses and discharges into the environment. The purpose of this study was to determine the water quality index of the effluent from waste stabilisation ponds and 400 m beyond discharge point. This was achieved by evaluating concentrations of seven parameters from soil, eleven physiochemical parameters from effluent and four microbiological parameters. Corresponding water quality indices calculated from microbiological parameters were 854, 142, 96 and 1539 respectively, at sites 1, 2, 3 and 4. Reductions of magnesium, zinc, lead, sodium adsorption ratio, sodium and electrical conductivity in soil samples at site 4 were 15.5%, 57%, 81.6%, 93.5%, 93.5% and 99% respectively. The percentage increases were 21.4% and 185% respectively, for calcium and iron ions. It can be concluded that the water quality index of the waste stabilisation ponds is unsuitable for discharge into the environment. However, the results revealed improved quality downstream of discharge point. 展开更多
关键词 MICROBIOLOGICAL PARAMETERS physiochemical PARAMETERS SODIUM Absorption Ratio Soil Sampling Waste Stabilization PONDS Water Quality Index
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Quality Assessment of Surface and Drinking Water of Nakla Paurosova, Sherpur, Bangladesh
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作者 Sourav Sarker Shahin Mahmud +9 位作者 Razia Sultana Ritu Biswas Partha Protim Sarkar Md. Abul Munayem Nur-E-Alam   Md. Rayhan Ali Muhammad Wasim Md. Firoz Ali Md. Omar Faruque Fatematuz Zuhura Evamoni 《Advances in Microbiology》 2019年第8期703-727,共25页
Water is one of the most vital elements of ecosystem and human being, but unfortunately nowadays, the pollution of surface and drinking water is an alarming problem. The present work deals with the assessment of physi... Water is one of the most vital elements of ecosystem and human being, but unfortunately nowadays, the pollution of surface and drinking water is an alarming problem. The present work deals with the assessment of physicochemical and bacteriological profile of several pond, jar and tube-well water samples to ensure its suitability for using and drinking. Total 30 samples were randomly selected and collected from Nakla Paurosova of Sherpur district by following the standard procedure. Bacteriological analysis was carried out by following the standard bacteriological methods. Most of the surface water sampling points were polluted by dumping of waste, cattle wash and were not suitable for drinking or other domestic purposes. Among three heavy metals, only Iron was detected in six tube-well water samples, one was also positive to arsenic, rest of the water bodies were negative to all of these metals. In case of most of the water bodies, different physicochemical properties were below standard limit. In pond water, the Total Viable Count (TVC) ranged from 2.7 × 107 cfu/100ml to 4.4 × 1015 cfu/100ml and Total Coliform Count (TCC) were 3.4 × 105 cfu/100ml to 4.8 × 1013 cfu/100ml, where the mean concentration of Heterotrophic Plate Count (HPC) was 2.4 × 105 cfu/100ml and 1.8 × 105 cfu/100ml in jar and tube-well water respectively. On the other hand, the Total Coliform Count of supply water was 33 cfu/100ml and tube-well water was 14 cfu/100ml. Fecal coliform was detected in all of the pond water samples, four jar and three tube-well water too. E. coli was present in all pond water samples, and also detected in 80% supply and 50% tube-well water also. Shigella spp. was found in two pond water and in one supply water, where tube-well water was free from it. Salmonella spp. was also detected in 30% of pond and 20% of supply water, whereas absent in tube-well water. 50% of pond, 40% of supply and 30% of tube-well water were contaminated with Vibrio spp. The total counts of these pathogenic bacteria exceeded the acceptab 展开更多
关键词 physiochemical Parameters BACTERIAL Load ANTIBIOGRAM PUBLIC HEALTH Nakla Paurosova
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Evaluation of the Level and Impact of Selected Physiochemical Parameters of Fertilizer Effluent on Obinna River, Adani, Enugu State, Nigeria
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作者 Chizoba Chinelo Agu Matthew Chukwudi Menkiti +1 位作者 Bernard Ibezim Okolo Patrick Chukwudi Nnaji 《Journal of Water Resource and Protection》 2014年第7期722-730,共9页
This work quantitatively evaluates the level and impact of selected physiochemical properties of fertilizer effluent on the Obinna River of Adani, Enugu State, Nigeria. The fertilizer effluent originated from surround... This work quantitatively evaluates the level and impact of selected physiochemical properties of fertilizer effluent on the Obinna River of Adani, Enugu State, Nigeria. The fertilizer effluent originated from surrounding farms and flushed into the Obinna River. Water samples were collected from designated points along the river and analysed for physical, chemical and biological properties using standard methods of APHA. Impact of selected key parameters such as nitrate, phosphate, manganese, dissolved oxygen, biochemical oxygen demand and heavy metals (lead, iron and manganese), was studied. The results of the parameters were compared with the World Health Organisation (WHO) permissible standard for freshwater. Measured concentrations of phosphate (5.00, 7.21, 3.92 mg/L), manganese (1.53, 1.18, 1.47 mg/L) and lead (18.9, 21.7, 39.7 ppm) were found to be above the WHO standard while nitrate (0.04, 0.03, 0.03 mg/L) and iron (0.001, 0.001, 0.1 mg/L) were within the standard. The mean concentrations of heavy metals increased in the following order: Fe (0.034) 1 to downstream S3, with manganese and lead being above WHO standard. The results showed a level of significance for the chi-square distribution and correlation coefficients while the analysis of variance (ANOVA) results was conflicting. It could be inferred that the impact of the selected parameters contributed to the pollution of Obinna River. 展开更多
关键词 physiochemical HEAVY Metals WHO Pollution Obinna RIVER
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Assessment of Groundwater Quality and Saline Intrusions in Coastal Aquifers of Lagos Metropolis, Nigeria
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作者 Adewuyi Gregory Olufemi 《Journal of Water Resource and Protection》 2010年第10期849-853,共5页
As a result of immense industrialisation and high population growth, groundwater is heavily relied on in Lagos metropolis to serve as an alternative source of water where surface water is seriously polluted. The conti... As a result of immense industrialisation and high population growth, groundwater is heavily relied on in Lagos metropolis to serve as an alternative source of water where surface water is seriously polluted. The continued reliance on ground water has resulted in its decline in quantity and quality. In this study, the coastal aquifers of Lagos metropolis were selected for an assessment of its groundwater quality and impact of saline intrusion. Water samples collected along the coastal region were subjected to various physicochemical analyses. Results obtained were compared with permissible values for drinking water stated by Federal Environmental Protection Agency (FEPA) and World Health Organization (WHO). The results revealed that all the water samples were significantly hard (range 522.14 – 1233.34mg/L). The salinity was delineated by conductivity measurements. Three samples had specific conductance above the stated limits for fresh water. The samples however met the stipulated limits for drinking water for the other tested parameters. 展开更多
关键词 INDUSTRIALISATION GROUNDWATER physiochemical Analysis SALINITY Conductivity
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