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霉菌发酵剂对干发酵香肠的理化指标、氧化程度及风味的影响 被引量:24
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作者 蔡嘉铭 王际辉 +3 位作者 陶冶 肖珊 刘冰南 王亮 《食品与发酵工业》 CAS CSCD 北大核心 2020年第5期17-22,共6页
为探究将分离自传统宣威火腿中的霉菌作为优良发酵剂的可行性,将其中的枝孢菌P27作为发酵剂接种于干发酵香肠中,研究其对干发酵香肠理化性质、氧化程度以及风味的影响。结果表明,枝孢菌没有显著地改变干发酵香肠的pH和水分活度值,但使... 为探究将分离自传统宣威火腿中的霉菌作为优良发酵剂的可行性,将其中的枝孢菌P27作为发酵剂接种于干发酵香肠中,研究其对干发酵香肠理化性质、氧化程度以及风味的影响。结果表明,枝孢菌没有显著地改变干发酵香肠的pH和水分活度值,但使细菌总数显著降低,并且通过降低香肠硬度、增加香肠弹性而改善香肠质构。不同加工阶段接菌组香肠的脂肪氧化和蛋白质氧化程度显著低于空白组,说明枝孢菌具有一定的抗氧化能力。通过气质联用仪对发酵30 d后的干发酵香肠的风味物质进行检测,共检出23种物质,发现接菌组香肠的醇类、酯类、酮类和萜类等物质含量增多。综上所述,枝孢菌作为发酵剂可以减少干发酵香肠的杂菌含量、改善香肠质构、减缓香肠氧化、丰富香肠风味,未来可作为发酵剂应用于发酵肉制品的生产。 展开更多
关键词 枝孢菌 干发酵香肠 理化指标 抗氧化 风味
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活性污泥系统原生动物多样性动态及其与运转效能的关系 被引量:7
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作者 周可新 许木启 +1 位作者 曹宏 刘标 《应用与环境生物学报》 CAS CSCD 北大核心 2007年第6期840-842,共3页
研究了保定鲁岗污水处理厂活性污泥系统原生动物多样性动态及其与理化参数的关系.结果表明,为附着型纤毛虫的香农-威纳多样性指数最高,平均为2.25.自由游泳型纤毛虫的多样性指数最低,平均为0.27.各类群原生动物多样性指数与理化参数间... 研究了保定鲁岗污水处理厂活性污泥系统原生动物多样性动态及其与理化参数的关系.结果表明,为附着型纤毛虫的香农-威纳多样性指数最高,平均为2.25.自由游泳型纤毛虫的多样性指数最低,平均为0.27.各类群原生动物多样性指数与理化参数间相关分析的结果表明,匍匐型纤毛虫多样性指数对出水BOD5的指示效果最好,附着型纤毛虫多样性指数高则表明出水P浓度高,肉食型纤毛虫多样性值对出水氨氮及SVI具有较强的指示作用,有壳肉足虫多样性值对SVI的指示效果较好,裸肉足虫多样性值对出水氨氮浓度具有较好的指示作用. 展开更多
关键词 原生动物 活性污泥 多样性 理化参数
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蛋氨酸铜对西门塔尔牛日粮养分消化代谢及血液指标的影响 被引量:6
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作者 王聪 董宽虎 +3 位作者 刘强 黄应祥 裴华 刘曦 《中国生态农业学报》 CAS CSCD 2008年第6期1523-1527,共5页
选用16头平均体重420 kg、年龄2.5岁的中国西门塔尔牛阉牛,采用随机区组设计分为4组,以混合精料和风干玉米秸秆为基础日粮,以蛋氨酸铜为铜源,在基础日粮中分别添加铜0 mg·kg-1、8 mg·kg-1、16mg·kg-1和24 mg·kg-1,... 选用16头平均体重420 kg、年龄2.5岁的中国西门塔尔牛阉牛,采用随机区组设计分为4组,以混合精料和风干玉米秸秆为基础日粮,以蛋氨酸铜为铜源,在基础日粮中分别添加铜0 mg·kg-1、8 mg·kg-1、16mg·kg-1和24 mg·kg-1,研究蛋氨酸铜对西门塔尔牛营养物质消化代谢和血液指标的影响。结果表明:添加铜处理可显著提高有机物质(OM)、粗蛋白质(CP)、粗脂肪(EE)和无氮浸出物(NFE)消化率(P<0.05)。8 mg·kg-1和16 mg·kg-1处理组显著提高中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)消化率(P<0.05)。蛋氨酸铜补充组显著提高消化氮(DN)、沉积氮(RN)和RN/DN。8~16 mg·kg-1蛋氨酸铜补充组较0 mg·kg-1组显著增加血清甘油三酯(TG)、葡萄糖(GLU)、总胆固醇(TC)、白蛋白(ALB)和总蛋白(TP)含量(P<0.05)。24 mg·kg-1处理组血清尿素氮(SUN)明显低于对照组(P<0.05)。随着蛋氨酸铜添加水平的提高,各组间血清谷草转氨酶(GOT)、谷丙转氨酶(GPT)、碱性磷酸酶(AKP)、酸性磷酸酶(ACP)、乳酸脱氢酶(LDH)差异均不显著(P>0.05),血清铜蓝蛋白(Cp)逐渐增加(P<0.05),超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-px)活性显著提高(P<0.05),丙二醛(MDA)呈下降趋势(P<0.05)。16 mg·kg-1和24mg·kg-1处理组血清铜含量显著高于对照和8 mg·kg-1处理组(P<0.05)。根据试验结果,蛋氨酸铜添加量以8~16 mg·kg-1为宜。 展开更多
关键词 西门塔尔牛 蛋氨酸铜 消化率 氮平衡 生化指标
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牛粪堆肥中反硝化细菌与理化参数的关系 被引量:6
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作者 朱丽平 许修宏 +4 位作者 张文浩 成利军 李洪涛 王紫琪 贺宁 《农业环境科学学报》 CAS CSCD 北大核心 2016年第9期1781-1787,共7页
以nos Z基因为标记,应用聚合酶链式反应-变性梯度凝胶电泳法(PCR-DGGE)对牛粪堆肥过程中反硝化细菌群落结构进行研究,通过冗余分析(Redundancy analysis,RDA)法,分析反硝化细菌群落结构变化与堆肥过程中理化参数(堆体温度、pH、含... 以nos Z基因为标记,应用聚合酶链式反应-变性梯度凝胶电泳法(PCR-DGGE)对牛粪堆肥过程中反硝化细菌群落结构进行研究,通过冗余分析(Redundancy analysis,RDA)法,分析反硝化细菌群落结构变化与堆肥过程中理化参数(堆体温度、pH、含水率、氨态氮和硝态氮)之间的关系。结果表明,反硝化细菌群落的Shannon-Weaver指数在堆肥0~4 d升高,在7~29 d减小。对优势条带进行测序发现Alcaligenes存在于整个堆肥过程中,判定其为此过程中优势菌属。反硝化细菌群落结构在堆肥前期(0~4 d)变化较小,而在降温腐熟期(23~29 d)变化剧烈。皮尔逊相关系数分析表明,反硝化细菌群落多样性与含水率呈极显著正相关关系(r=0.960,P〈0.01),与温度呈显著正相关关系(r=0.766,P〈0.05)。 展开更多
关键词 堆肥 反硝化细菌 理化参数 群落结构 冗余分析
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Hydrochemical Characterization of Groundwater in the Sub-Prefecture of Kokumbo (Ivory Coast)
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作者 Armel Kouadio Koblan Affoué Bénédicte Koffi +3 位作者 Aminata Diomandé Deh Serges Kouakou Kan Jean Kouamé Jean Patrice Jourda 《Journal of Geoscience and Environment Protection》 2023年第6期169-183,共15页
In the Kokumbo sub-prefecture, groundwater extraction related to gold panning remains a major concern, not to mention the deterioration of its quality. Among the work carried out on water resources, no scientific inte... In the Kokumbo sub-prefecture, groundwater extraction related to gold panning remains a major concern, not to mention the deterioration of its quality. Among the work carried out on water resources, no scientific interest has been shown in groundwater to characterise it. The objective of this study is to contribute to the knowledge of its physico-chemical quality. In situ measurements and physico-chemical analyses using an inductively coupled plasma optical emission spectrometer (ICP-OES) were carried out on five (5) human-powered pump (HPP) water samples and six (6) well water samples collected during low and high water seasons. The results show that the physico-chemical quality of the water, which is sometimes turbid, is satisfactory in terms of the mineralization of the borehole and well water, and the pH of the boreholes, while the temperatures of the two waters and the pH of the wells do not comply with WHO standards. The levels of major ions are recommended for consumption. The waters are classified as predominantly bicarbonate-calcium and magnesium (73%) in the dry season and in the flood season, with an equal split between bicarbonate-calcium and magnesium (45.5%) and chloride-calcium and magnesium (45.5%). The elimination of materials responsible for the turbidity of certain waters by managers or populations is essential for drinking water use. The risk linked to this element means that these turbid waters are not recommended for drinking water. 展开更多
关键词 GROUNDWATER physico-chemical parameter Hydrochemical Facies Kokumbo
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二元可燃混合气体爆炸上限的理论预测 被引量:1
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作者 李国梁 潘勇 +1 位作者 蒋军成 李高艳 《燃烧科学与技术》 EI CAS CSCD 北大核心 2013年第2期175-180,共6页
确定了影响可燃气体爆炸上限的特征理化因素,如化学计量浓度、临界压力和燃烧热等,构建了混合物理化参数来表征混合气体的理化特征.将这些参数作为输入变量,分别应用多元线性回归和多元非线性回归方法对二元可燃混合气体爆炸上限与上述... 确定了影响可燃气体爆炸上限的特征理化因素,如化学计量浓度、临界压力和燃烧热等,构建了混合物理化参数来表征混合气体的理化特征.将这些参数作为输入变量,分别应用多元线性回归和多元非线性回归方法对二元可燃混合气体爆炸上限与上述混合物理化参数之间的内在相关性进行研究,建立了根据混合物理化参数预测二元可燃混合气体爆炸上限的数学模型.两种方法对训练集的预测平均绝对误差分别为2.39%和1.272%;对测试集的预测平均绝对误差分别为2.185%和1.888%.结果表明,两种模型爆炸上限的预测值与文献值均符合较好,在可接受误差范围之内.该方法的提出为工程上提供了一种预测二元可燃混合气体爆炸上限的新方法. 展开更多
关键词 二元可燃 混合气体 爆炸上限 理化参数 预测模型
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Physico-Chemical Quality of Lake Kyoga at Selected Landing Sites and Anthropogenic Activities
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作者 Robert Ongom Morgan Andama Ben Lukubye 《Journal of Water Resource and Protection》 2017年第11期1225-1243,共19页
Lake Kyoga, one of the great African lakes in Uganda is facing an increasing pressure from human activities yet there is limited information on water quality of the lake. Therefore this study determined selected physi... Lake Kyoga, one of the great African lakes in Uganda is facing an increasing pressure from human activities yet there is limited information on water quality of the lake. Therefore this study determined selected physico-chemical parameters of Lake Kyoga at some landing sites (Kayei, Acholi inn, Waitumba, Masindi port) and anthropogenic activities (boat dock, waste site, garden, fishing). The parameters included temperature, pH, water flow rate, dissolved oxygen (DO), nitrite (NO2-) and phosphate (PO4-P). The American Public Health Association (APHA) and Water Watch Australia protocols, standard meters, Merck’s rapid test kits and timing of a float were used to measure the parameters. The results showed that the mean temperature, pH, DO, and PO4-P significantly (p 2- levels were within the EPA drinking water guideline of 0.5 mg/l. The orthophosphates (PO4-P) were highest in the waste sites (0.35 mg/l), followed by gardens (0.24 mg/l) and least in the fishing areas (0.12 mg/l). However, phosphates in the form of P2O5 were higher than the EPA standard value (0.5 mg/l) at Kayei (0.55 mg/l) and Acholi inn (0.55 mg/l) landing sites as well as at waste sites (0.80 mg/l) and gardens (0.55 mg/l) pointing to high nutrient (phosphorus) input at these sites. The high concentrations of nitrites in Lake Kyoga at the investigated anthropogenic activities and landing sites plus phosphate amounts close to waste sites and gardens including Kayei and Acholi inn landing sites call for vigilance in protection of Lake Kyoga through optimized planning. Hence, National Environment Management Authority should ensure proper sewage management in Lake Kyoga catchment to avoid discharge of untreated sewage into the lake. The authority should also regulate waste dumping and cultivation around the lake so as to reduce nutrient (phosphorus) enrichment. 展开更多
关键词 ANTHROPOGENIC Activity LAKE Kyoga LANDING SITE physico-chemical parameter
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Prediction of hydrophobic regions effectively in transmembrane proteins using digital filter
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作者 Jayakishan Meher Mukesh Kumar Raval +1 位作者 Gananath Dash Pramod Kumar Meher 《Journal of Biomedical Science and Engineering》 2011年第8期562-568,共7页
The hydrophobic effect is the major factor that drives a protein molecule towards folding and to a great degree the stability of protein structures. Therefore the knowledge of hydrophobic regions and its prediction is... The hydrophobic effect is the major factor that drives a protein molecule towards folding and to a great degree the stability of protein structures. Therefore the knowledge of hydrophobic regions and its prediction is of great help in understanding the structure and function of the protein. Hence determination of membrane buried region is a computationally intensive task in bioinformatics. Several prediction methods have been reported but there are some deficiencies in prediction accuracy and adaptability of these methods. Of these proteins that are found embedded in cellular membranes, called as membrane proteins, are of particular importance because they form targets for over 60% of drugs on the market. 20-30% of all the proteins in any organism are membrane proteins. Thus transmembrane protein plays important role in the life activity of the cells. Hence prediction of membrane buried segments in transmembrane proteins is of particular importance. In this paper we have proposed signal processing algorithms based on digital filter for prediction of hydrophobic regions in the transmembrane proteins and found improved prediction efficiency than the existing methods. Hydrophobic regions are extracted by assigning physico-chemical parameter such as hydrophobicity and hydration energy index to each amino acid residue and the resulting numerical representation of the protein is subjected to digital low pass filter. The proposed method is validated on transmembrane proteins using Orientation of Proteins in Membranes (OPM) dataset with various prediction measures and found better prediction accuracy than the existing methods. 展开更多
关键词 HYDROPHOBIC Region TRANSMEMBRANE Protein WAVELET TRANSFORM physico-chemical parameter Digital Filter
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Aloe vera Coating Efficiency on Shelf Life of Eggplants at Differential Storage Temperatures
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作者 Sikandar Amanullah Mtthammad Muzammil Jahangir +3 位作者 Rao Muhammad Ikram Mateen Sajid Farhat Abbas Ali Inayat Mallano 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第4期15-25,共11页
The core objective of instant study was to check the effectiveness of Aloe vera edible coating on postharvest life and physicochemical characteristics of eggplants under different storage temperatures. For this purpo... The core objective of instant study was to check the effectiveness of Aloe vera edible coating on postharvest life and physicochemical characteristics of eggplants under different storage temperatures. For this purpose, different formulations of Aloe vera based coating (non-poisonous) was applied at concentration of 0, 0.1%, 0.5%, and 1.0%, respectively on eggplants. The coated eggplants were stored at two different temperatures [10℃ and (30±2)℃] and examined for weight loss, firmness, stem color, shriveling, total soluble solids, pH, acidity, vitamin C, sugar (total sugar, reducing sugar and non-reducing sugar) and N, P, K, Ca and Na for two weeks. The obtained results showed that weight loss, shriveling, total soluble solids, pH, sugar (total sugar and non-reducing sugar) increased and firmness, stem color, acidity, reducing sugar, vitamin C minimized during the storage period. The 0.5% Aloe coating at 10℃ showed significant effect and delayed the changes in above parameters. Aloe vera coating remained almost ineffective in altering nutrient homeostasis (N, P, K, Ca and Na) of eggplants. The optimistic results gained in the current study could additionally investigate in larger market experiments and also could extensive to other tropical/subtropical fruits and vegetables. 展开更多
关键词 EGGPLANT Aloe vera coating storage temperature shelf life physico-chemical parameter
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解毒止血汤水提液中黄芩苷、汉黄芩苷、丹皮酚含量及其理化参数测定 被引量:1
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作者 刘李梅 谢松 +3 位作者 彭伟 向猛 郭宏彦 涂禾 《国际中医中药杂志》 2020年第1期62-66,共5页
目的:建立测定解毒止血汤水提液中黄芩苷、汉黄芩苷、丹皮酚含量的方法,并测定其理化参数。方法:采用HPLC法检测解毒止血汤水提液中黄芩苷、汉黄芩苷、丹皮酚含量。色谱柱为Waters Symmetry Shield TMRP18柱(4.6 mm×250 mm,5μm),... 目的:建立测定解毒止血汤水提液中黄芩苷、汉黄芩苷、丹皮酚含量的方法,并测定其理化参数。方法:采用HPLC法检测解毒止血汤水提液中黄芩苷、汉黄芩苷、丹皮酚含量。色谱柱为Waters Symmetry Shield TMRP18柱(4.6 mm×250 mm,5μm),流动相为乙腈-0.1%磷酸水溶液,梯度洗脱,流速为1 ml/min,检测波长274 nm,柱温30℃。测定解毒止血汤水提液的pH值及相对密度。结果:黄芩苷在0.1912~1.1472μg范围内线性良好,汉黄芩苷在0.0415~0.2074μg范围内线性良好,丹皮酚在0.0195~0.1563μg范围内线性良好。该方法重现性、稳定性、回收率均良好。3批解毒止血汤水提液中黄芩苷、汉黄芩苷、丹皮酚含量无显著差异,其pH值范围为5.240~5.753,相对密度范围为0.846~0.889。结论:本文所建立方法可测定解毒止血汤水提液中多个有效成分,方法稳定、可行,适用于解毒止血汤水提液的质量控制。 展开更多
关键词 剂型改进 解毒止血汤 黄芩苷 汉黄芩苷 丹皮酚 理化参数 高效液相色谱法 质量控制
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Assessment of groundwater quality in the flood plains of upper Palar River, India 被引量:1
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作者 Rutharvel Murthy Kuppuraj Dhanakumar Selvaraj +3 位作者 Solaraj Govindaraj Mohanraj Rangaswamy Jawahar Raj Narayanasamy Kumaraswamy Kuppanagounder 《Chinese Journal Of Geochemistry》 EI CAS 2012年第1期15-23,共9页
Groundwater is generally presumed to be good for human consumption and is used as a main source of drinking water. Although there are numerous reasons for groundwater pollution, anthropogenic sources are consid-ered a... Groundwater is generally presumed to be good for human consumption and is used as a main source of drinking water. Although there are numerous reasons for groundwater pollution, anthropogenic sources are consid-ered as the prime ones. In this study, twenty-two groundwater samples were collected from the flood plains of upper Palar River during the pre- and post-monsoon seasons to assess the extent of pollution and effects on human health. Physico-chemical characteristics of groundwater were analyzed and compared with those of drinking water standards recommended by the World Health Organization (WHO) and the Bureau of Indian Standards (BIS). The Piper's tri-linear diagram shows the nature of alkali earth with the high contents of alkalies and prevailing sulphate in the pre-sent samples. The univariate statistics and correlation analysis were performed to find out the relationships between the variables. The tannery effluents, solid wastes and sewage were suspected to be the predominant sources of pollu-tion in the area. 展开更多
关键词 地下水污染 冲积平原 水质评价 印度 饮用水标准 上游 物理化学特性 世界卫生组织
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用微型动物预测保定鲁岗污水处理厂活性污泥系统理化参数 被引量:1
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作者 周可新 许木启 曹宏 《动物学杂志》 CAS CSCD 北大核心 2007年第4期57-59,共3页
用微型动物预测了保定鲁岗污水处理厂活性污泥系统的理化参数。建立的4个多元线性回归方程对出水BOD5、出水TN、SVI和出水SS做预测,分别需5、5、8和5种微型动物,预测成功率分别为78·7%、79·3%、89·5%和62·3%。
关键词 微型动物 活性污泥 理化参数
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热液金矿床控矿断裂性质与成矿流体的物理化学 被引量:6
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作者 徐九华 谢玉玲 申世亮 《地球学报(中国地质科学院院报)》 CSCD 北大核心 1998年第2期204-209,共6页
热液金矿床的成矿物理化学条件与控矿断裂构造环境有着密切联系。作者对比了不同构造环境(小秦岭、焦家、玲珑和太白金矿)流体包裹体物理化学参数特征,表明韧性剪切带环境中的金矿成矿流体压力大、CO2/H2O数值也高。不同构造... 热液金矿床的成矿物理化学条件与控矿断裂构造环境有着密切联系。作者对比了不同构造环境(小秦岭、焦家、玲珑和太白金矿)流体包裹体物理化学参数特征,表明韧性剪切带环境中的金矿成矿流体压力大、CO2/H2O数值也高。不同构造环境中流体K+/Na+、F-/Cl-的差别不仅与容矿岩石化学特征有关,也与构造应力作用有关,同一矿田内,甚至同一断裂带内,因所处构造部位不同,成矿流体压力也不同,致使其他物理化学参数的系统变化,这对地质找矿具有实际意义。 展开更多
关键词 金矿床 构造环境 包裹体 物理化学参数 成矿流体
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Efficient Microorganism Compost Benefits Plant Growth and Improves Soil Health in Calendula and Marigold 被引量:3
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作者 Anamika Sharma Tarak Nath Saha +2 位作者 Anju Arora Raghubir Shah Lata Nain 《Horticultural Plant Journal》 SCIE 2017年第2期67-72,共6页
Organic farming needs to be promoted as a means of sustaining soil health and reducing the cost of farming, especially for small farmers.The present study deals with the effect of organic compost, prepared using Effic... Organic farming needs to be promoted as a means of sustaining soil health and reducing the cost of farming, especially for small farmers.The present study deals with the effect of organic compost, prepared using Efficient Microorganism(EM) consortium and applied along with full or half of the recommended dose of chemical fertilizers, on the growth of Calendula and Marigold plants, soil physico-chemical parameters and soil enzyme activities. Soil enzyme activities were improved with the increase in the rate of EM compost application in both Calendula and Marigold. Carotenoid pigment increased by 46.11% and 12.19% with application of EM compost over the control in Calendula and Marigold flowers respectively. Soil humus, available nitrogen and organic carbon content also increased due to the supplementation of EM compost resulting in better soil fertility. For Calendula, treatment T5(Half dose NPK + EM compost 20 000 kg·hm^(-2)) was found to be the most promising in terms of acid phosphatase(82.63 μg p-Nitrophenyl Phosphate·g^(-1)·h^(-1)), dehydrogenase(10.46 μg Triphenyl Formazan·g^(-1)·d^(-1)) and β-glucosidase(0.30 IU·g^(-1)) activities. In Marigold, treatment C(Half dose NPK + EM compost 5 000 kg·hm^(-2)) was the most promising in terms of amendment in soil enzyme activities. 展开更多
关键词 calendula MARIGOLD EM compost soil fertility plant growth soil enzyme activity soil physico-chemical parameter
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甘肃省安家岔金矿床矿物包裹体研究 被引量:3
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作者 谭立群 《贵金属地质》 1994年第4期248-261,共14页
本文从石英包裹体的气液相成分分析数据和均一温度测定结果出发,计算出矿床的成矿压力、成矿热液的物理比学参数及其化学成分特征参数。结合矿床地质特征对矿床的成矿温度、矿床成矿热液的性质和来源、热液的流动方向、热液化学成分与... 本文从石英包裹体的气液相成分分析数据和均一温度测定结果出发,计算出矿床的成矿压力、成矿热液的物理比学参数及其化学成分特征参数。结合矿床地质特征对矿床的成矿温度、矿床成矿热液的性质和来源、热液的流动方向、热液化学成分与金矿化的关系、热液中金的迁移形式和沉淀机制等问题作了进一步地探讨。结果表明,安家岔金矿床具有改造型金矿床的成因特点。 展开更多
关键词 金矿床 矿物包体 气液相成分
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硝基多环芳烃的致突变性与理化参数之间的定量结构活性关系
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作者 余刚 徐晓白 《重庆环境科学》 1994年第2期13-16,41,共5页
硝基多环芳烃因具有直接致突变性、潜在致癌性以及在环境中的广泛存在而引起人们的关注。本文在硝基多环芳烃的致突变活性与理化参数(正辛醇-水分配系数、水溶解度、分子连接性指数)之间建立了10个定量结构活性关系式。并利用溶解... 硝基多环芳烃因具有直接致突变性、潜在致癌性以及在环境中的广泛存在而引起人们的关注。本文在硝基多环芳烃的致突变活性与理化参数(正辛醇-水分配系数、水溶解度、分子连接性指数)之间建立了10个定量结构活性关系式。并利用溶解度与致突变性之间的结构活性关系对50种硝基多环芳烃的致突变能力进行预测,正确率达78%。 展开更多
关键词 硝基多环芳烃 致突变 理化参数
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铜和维生素A及互作效应对肉仔鸡生产性能及理化指标的影响 被引量:13
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作者 张春善 高林青 +6 位作者 宋金昌 申红星 曹威荣 杨燕燕 王锋 蒋燕侠 常亚琪 《畜牧兽医学报》 CAS CSCD 北大核心 2006年第9期940-945,共6页
选用1日龄艾维茵肉仔鸡448只,随机分为8组,每组4个重复,每重复14只(公母各半)。采用4×2(Cu×VA)完全随机试验设计,研究了日粮添加不同水平的Cu(0,8,150,225mg/kg)和维生素A(1500,5000IU/kg),对肉仔鸡不同... 选用1日龄艾维茵肉仔鸡448只,随机分为8组,每组4个重复,每重复14只(公母各半)。采用4×2(Cu×VA)完全随机试验设计,研究了日粮添加不同水平的Cu(0,8,150,225mg/kg)和维生素A(1500,5000IU/kg),对肉仔鸡不同生长阶段(0~4周龄和5~7周龄)的生产性能及理化指标的影响。结果表明:铜的适宜添加量,前期为8mg/kg,后期为O~8mg/kg;全期高铜抑制了肉仔鸡生产性能、免疫功能、CuZn—SOD活性及胰岛素浓度;维生素A(5000IU/kg)组获得较好的生产性能、免疫功能及CuZn-SOD活性,并显著(P〈0.05)抑制了血清胰岛素浓度;Cu与维生素A互作效应对前期体增重及全期料重比影响均显著(P〈0.05),对后期淋巴细胞ANAE^+%、全期血清CuZn—SOD活性及前期血清胰岛素浓度影响均极显著(P〈0.01),且二者间存在互补作用。 展开更多
关键词 肉仔鸡 Cu 维生素A 互作效应 生产性能 理化指标 免疫功能 CuZn—SOD活性 胰岛素水平
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几种柑橘品种制汁适应性评价研究 被引量:11
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作者 谢姣 王华 马亚琴 《食品科学》 EI CAS CSCD 北大核心 2010年第17期153-157,共5页
利用感官及理化指标的综合评价研究北碚447#锦橙、中育七号#甜橙、雪柑#锦橙、江津长叶橙、溆浦哈姆林甜橙、洪江大红甜橙、无核大红甜橙和溆浦长型无核甜橙的制汁适应性,其中,感官评价使用百分法进行评定,理化指标的评定包括出汁率、... 利用感官及理化指标的综合评价研究北碚447#锦橙、中育七号#甜橙、雪柑#锦橙、江津长叶橙、溆浦哈姆林甜橙、洪江大红甜橙、无核大红甜橙和溆浦长型无核甜橙的制汁适应性,其中,感官评价使用百分法进行评定,理化指标的评定包括出汁率、可溶性固形物、可滴定酸、总黄酮、精油、柠檬苦素等12项。通过实验得出北碚447#锦橙、中育七号#甜橙、江津长叶橙、雪柑#锦橙、溆浦哈姆林甜橙、无核大红甜橙综合评分均高于80分,为适宜制汁品种;而洪江大红甜橙和溆浦长型无核甜橙固酸比均低于10,综合评分均高于75分,为可以制汁品种。 展开更多
关键词 制汁 适应性 理化指标
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Physico-Chemical and Structural Assessment of Akono Riparian Forest Watershed, Tributary of the Nyong Basin (Centre-Cameroon) at Different Stages of Degradation
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作者 Nwamo Roland Didier Gordon Nwutih Ajonina +1 位作者 Ndzougou Nkodo Colette Rose Tomedi Eyango Minette 《Journal of Environmental Protection》 2024年第5期552-571,共20页
Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as the... Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as they contain rivers which are vital sources of fresh water for local populations. However, the quality and quantity of water issued from the watershed depend on the structural state of these forests. The aim of this work was to assess the physico-chemical and structural state of the Akono gallery forest. To achieve this, fieldwork consisted of selecting six major streams of the watershed including Ndjolong, Menyeng adzap, Emomodo, Mvila, Negbe and Ossoé kobok. On each of these, two stations, one intact and one degraded, were marked by transects. The method involved measuring Hydrometric parameters (depth, length, width) of the stream and Physico-chemical parameters of water in the streams while dendrometric parameters were measured along 100 m-transects laid using the point-centred quarter method modified for water bodies to collect tree, shrub and palm variables such as trunk diameter, crown diameter and height. Macrophytes and species identification were carried out using standard botanical procedures. Results showed that, the majority of physico-chemical parameters measured differed significantly between intact and degraded stations (P Pentachletra mancrophylla, whereas on degraded sites, this index was low and characterized by the relative dominance of species Piptadeniastrum africanum. Sorensen’s index (0.56) and CFA showed that the different stands were homogeneous. We can affirm that the riparian forests of Akono watershed are towards a state of stability notwithstanding the perpetuation of anthropological actions. 展开更多
关键词 Akono Gallery Forest physico-chemical parameters Floristic Diversity Dendrometric parameters
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Characteristics and Dynamic of Algal Communities in a New Impounded Hydro-Agricultural Dam Lake (Samendeni Reservoir) in Burkina Faso (Western Africa)
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作者 Frédéric A. Kabré Souleymane Sanogo Bilassé Zongo 《Journal of Water Resource and Protection》 CAS 2024年第11期671-694,共24页
Proliferation of microalgae is the result of a complex interaction between hydrological and physico-chemical variables influenced by climatic and anthropogenic factors. This study assessed algal communities in the Sam... Proliferation of microalgae is the result of a complex interaction between hydrological and physico-chemical variables influenced by climatic and anthropogenic factors. This study assessed algal communities in the Samendeni Dam Lake to serve as indicators of water quality for sustainable management of hydro-agricultural water resources. Therefore, physico-chemical parameters and microalgae were monitored in three sampling zones from November 2021 to October 2022. A comparison of physico-chemical parameters was realized between sampling zones and between seasons. CCA and RDA were used to establish the relationship between parameters and microalgae. The results show 96 species belonging to 46 genera, 30 families, 19 orders, 9 classes, and 7 phyla. Charophyta dominated microalgal communities in both dry and rainy seasons. Phytoplankton species reached 34 in the dry season and 41 in the rainy season, whereas periphyton revealed 41 species in both seasons. Phytoplankton abundances ranged from 213 to 5440 cells·mL−1 and 3 to 110 cells·cm−2 for periphyton. At p < 0.05, significant correlation of Charophyta with pH (r = 0.39, p-value = 0.04), EC (r = −0.41 - 0.91, p-value = 0.00 - 0.03), Transp (r = 0.73, p-value = 0.03), Ammo (r = 0.48, p-value = 0.01), Nitra (r = 0.81, p-value = 0.01), Nitri (r = 0.91, p-value = 0.00) was observed. Bacillariophyta significantly correlated to pH (r = 0.70, p-value = 0.04), EC (r = −0.51 - 0.94, p-value = 0.00 - 0.04), DO (r = −0.70 - 0.81, p-value = 0.01 - 0.04), Transp (r = −0.71 - 0.73, p-value = 0.02 - 0.03), Nitra (r = 0.84, p-value = 0.00) and OrthoP (r = 0.44 - 0.73, p-value = 0.02 - 0.03). Chlorophyta was significantly correlated to EC (r = −0.41 - 0.95, p-value = 0.00 - 0.03), Transp (r = −0.52, p-value = 0.01), Nitra (r = 0.71, p-value = 0.03), Ammo (r = 0.42, p-value = 0.03). Cyanophyta showed significant correlation with pH (r = 0.43, p-value = 0.02);EC (r = 0.68, p-value = 0.04), Transp (r = −0.44, p-value = 0.02), OrthoP (r = 0.44 - 0.54, p-value = 0.00 展开更多
关键词 PHYTOPLANKTON PERIPHYTON physico-chemical parameters Water Quality Samendeni Dam Lake
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