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长江水质酸化与黄河水质浓化趋势及成因探讨 被引量:9
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作者 陈静生 夏星辉 洪松 《中国工程科学》 2000年第3期54-58,共5页
对我国水利部《水文年鉴》上所载长江、黄河所有水文站自 2 0世纪 5 0年代末至 80年代中期的水化学监测数据 ,以及全球水质监测计划中国站点 1 979~ 1 994年的水质监测资料进行分析研究 ,发现就天然水主要离子组分而言 ,长江中上游和... 对我国水利部《水文年鉴》上所载长江、黄河所有水文站自 2 0世纪 5 0年代末至 80年代中期的水化学监测数据 ,以及全球水质监测计划中国站点 1 979~ 1 994年的水质监测资料进行分析研究 ,发现就天然水主要离子组分而言 ,长江中上游和黄河表现出各自独特的水质变化趋势 ,即长江水质的酸化趋势和黄河水质的浓化趋势。 展开更多
关键词 长江 黄河 水质 水质酸化 水质 成因 水质监测 水污染
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水质酸化对双棘臂尾轮虫种群动态的影响 被引量:2
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作者 席贻龙 黄祥飞 《湖泊科学》 EI CAS CSCD 1999年第2期155-159,共5页
用人工酸化的东湖水为培养液对双棘臂尾轮虫进行室内单个体培养研究.结果表明,与用未酸化的东湖水培养结果相比,轮虫非混交雌体的平均产卵量在 pH6. 5、5 5和 4. 5时增加,而在 pH3.5时减少.在 pH5.5和 3.5... 用人工酸化的东湖水为培养液对双棘臂尾轮虫进行室内单个体培养研究.结果表明,与用未酸化的东湖水培养结果相比,轮虫非混交雌体的平均产卵量在 pH6. 5、5 5和 4. 5时增加,而在 pH3.5时减少.在 pH5.5和 3.5时轮虫种群的内禀增长率增大,种群中无混交雌体出现;而在pH6.5和4.5时内禀增长率减小,混交雌体百分率增大.在本实验pH范围内,双棘臂尾轮虫具有耐酸性. 展开更多
关键词 水质酸化 双棘臂尾轮虫 种群动态 人工
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海洋酸化趋重 生态灾难危及人类
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作者 王建燕 《地球》 2011年第9期39-41,共3页
近日,全球多地出现水母激增的现象。这些出现在英国、美国、日本、以色列等地的水母不仅吓坏了海边的游客,还干扰了核电站运行。科学家分析称,水母数量激增,可能与近年来人类使用化石燃料增多、导致海洋水质酸化有关。
关键词 水质酸化 生态灾难 海洋 人类 石燃料 水母 以色列 核电站
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液体酸化剂的评估及其对肉鸡生长性能的影响 被引量:9
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作者 任方奎 张桂芝 +3 位作者 张燕平 崔锦鹏 于立国 刘敦章 《饲料研究》 CAS 北大核心 2021年第1期49-52,共4页
试验旨在研究不同比例液体酸化剂对饮用水的酸化作用、水质硬度的软化效果、饮水中大肠杆菌的抑菌效果及酸化水对肉鸡生产性能的影响。结果显示:液体酸化剂能够能显著降低水的pH值(P<0.05);硬水中添加0.2%液体酸化剂能显著降低水的硬... 试验旨在研究不同比例液体酸化剂对饮用水的酸化作用、水质硬度的软化效果、饮水中大肠杆菌的抑菌效果及酸化水对肉鸡生产性能的影响。结果显示:液体酸化剂能够能显著降低水的pH值(P<0.05);硬水中添加0.2%液体酸化剂能显著降低水的硬度(P<0.05);0.2%液体酸化剂能显著抑制大肠杆菌生长(P<0.05)。以饮用0.2%液体酸化剂酸化后的饮用水的肉鸡作为试验组,饮用未经酸化的饮用水为对照组,结果显示:与对照组相比,试验组肉鸡21、42 d体重显著增加(P<0.05);22~42、0~42 d平均日增重显著增加(P<0.05);22~42 d平均日采食量显著增加(P<0.05);1~21、22~42、1~42 d料重比显著降低(P<0.05);1~21、22~42、1~42 d腹泻发生率显著降低(P<0.05);试验组肉鸡群粪便干爽、成型度好。研究表明,液体酸化剂能很好地酸化水质、降低水的硬度、抑制大肠杆菌的繁殖,酸化水可以提高肉鸡的生长性能。 展开更多
关键词 液体 水质 抑菌试验 生长性能 肉鸡
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利用生物炭技术处理酸性矿山废水的研究进展 被引量:8
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作者 田发荣 高佳丽 +6 位作者 朱周彩霞 万乾松 田洪敏 冯乾伟 蒋宗宏 陈淼 王兵 《环境化学》 CAS CSCD 北大核心 2022年第8期2712-2728,共17页
随着社会经济的不断发展,矿业开发过程中产生的一系列环境问题引起国内外的广泛关注,其中采矿过程中产生的酸性矿山废水(acid mine drainage,AMD)问题尤为突出.AMD会导致水质酸化、土壤重金属污染以及植物枯萎死亡等问题.因此,如何对AM... 随着社会经济的不断发展,矿业开发过程中产生的一系列环境问题引起国内外的广泛关注,其中采矿过程中产生的酸性矿山废水(acid mine drainage,AMD)问题尤为突出.AMD会导致水质酸化、土壤重金属污染以及植物枯萎死亡等问题.因此,如何对AMD进行有效处理已成为环境治理的焦点问题.现有的AMD处理方法主要包括中和法、人工湿地法和微生物法,但这些方法大多存在后续管理难、维护成本高、处理浓度低等问题.相比之下,生物炭技术因原料成本低、制备简便且原材料来源广泛等优点而被广泛应用于环境修复领域.近年来国内外已有关于利用生物炭技术处理AMD的研究报道,但其处理机制尚不清楚,许多研究还停留在实验室阶段,尚未形成规模化的应用模式.因此,本文首先对AMD的特征及其常用处理方法进行了概述,并介绍了生物炭的常规制备方法及理化性质表征,对生物炭处理AMD的影响因素、处理效果及其机理进行了综述,最后对生物炭技术在处理AMD方面的研究与应用进行了展望. 展开更多
关键词 生物炭 性矿山废水 水质酸化 处理技术 机理
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水库养鱼施肥技术
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作者 张晓丹 《农村实用科技信息》 2002年第12期32-32,共1页
一、水库的选择施肥养鱼是通过补充水体中N、P、K含量或调整其比来增加水体肥源,繁殖浮游生物,提高滤食性鱼类的产量。要求水库的水质良好,符合渔业水质标准,天旱不干涸,无有毒有害污染物流入,年水体交换量5次以下,水温大于20℃时间在1... 一、水库的选择施肥养鱼是通过补充水体中N、P、K含量或调整其比来增加水体肥源,繁殖浮游生物,提高滤食性鱼类的产量。要求水库的水质良好,符合渔业水质标准,天旱不干涸,无有毒有害污染物流入,年水体交换量5次以下,水温大于20℃时间在150d以上,平均水深8m以内,水草少、光照好。 展开更多
关键词 水库养鱼 浮游生物 滤食性鱼类 施肥养鱼 渔业水质标准 水体交换 水质酸化 无机肥 补充水 平均水深
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Effects of Self-purification of River Water on Laundry Wastewater
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作者 Liya TAN Yili CHEN +4 位作者 Liuying CHEN Linghan ZENG Yujie CAI Bingbing FENG Hai WANG 《Agricultural Science & Technology》 CAS 2017年第6期1023-1028,共6页
[Objective] This study was conducted to investigate the effect of laundry wastewater on the quality of river water and the dilution purification effect of river water on laundry wastewater. [Method] The effects of lau... [Objective] This study was conducted to investigate the effect of laundry wastewater on the quality of river water and the dilution purification effect of river water on laundry wastewater. [Method] The effects of laundry wastewater on the contents of total nitrogen(TN), total phosphorus(TP), suspended solids(SS), chemical oxygen demand(COD) and linear alkylbenzene sulfonic acid(LAS) were studied in 7 rivers of Shaoxing City. [Result](1) The contents of TN, TP, SS, COD and LAS increased by 92%, 99%, 340%, 351% and 923%, respectively, at the discharging moment of laundry wastewater; and(2) the five pollutional indexes significantly decreased over time, and especially 2 h after the discharge of laundry wastewater, compared with former the discharge of laundry wastewater, the contents of TN, TP, COD and LAS increased by 6%, 11%, 9% and13%, respectively,while the contents of SS still increased by 76%, i.e., SS required a longer time to achieve self-purification. [Conclusion] Laundry wastewater has some influence on thequality of river water, and the self-purification function of river water could effectively remove pollutants. 展开更多
关键词 Laundry wastewater SELF-PURIFICATION Total nitrogen Total phosphorus Linear alkylbenzene sulphonic acid
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Preparation and Crystal Structure of Sarcosine 5-Nitrosalicylic Acid Organic Adduct
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作者 金轶 车云霞 +1 位作者 魏荣敏 郑吉民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第11期1292-1294,共3页
The title compound (C10H12N2O7, Mr = 272.22) crystallizes in triclinic, space group P1 with a = 5.532(2), b = 9.760(4), c = 11.731(5) ?, α = 68.107(7), β = 89.179(7), γ = 77.830(7)o, V = 573.1(4) ?3, Z = 2, Dc = 1.... The title compound (C10H12N2O7, Mr = 272.22) crystallizes in triclinic, space group P1 with a = 5.532(2), b = 9.760(4), c = 11.731(5) ?, α = 68.107(7), β = 89.179(7), γ = 77.830(7)o, V = 573.1(4) ?3, Z = 2, Dc = 1.578 g/cm3, F(000) = 284 and μ(MoKa) = 0.136 mm-1. The final R = 0.0400 and wR = 0.0951 for 1468 observed reflections with I > 2σ(I). The title compound is a 1:1 adduct of sarcosine and 5-nitrosalicylic acid. The nitrogen atom of sarcosine is protonated, and the proton is from the carboxyl group of sarcosine and 5-nitrosalicylic acid with the probability of 50 percent for each. The 5-nitrosalicylic acid and sarcosine molecule of the title adduct are ABAB arranged along the c axis. There exist a lot of hydrogen bonds in the structure, linking sarcosine and 5-nitrosalicylic acid to form a three-dimensional network. 展开更多
关键词 crystal structure SARCOSINE 5-nitrosalicylic acid hydrogen bond PROTONATED three-dimensional network
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Dynamics of liquid-phase catalytic oxidation of hydrogen sulfide removal in rural biogas
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作者 贾丽娟 宁平 +2 位作者 王向宇 瞿广飞 熊向锋 《Journal of Central South University》 SCIE EI CAS 2014年第7期2843-2847,共5页
Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and su... Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and sulfur capacity of the composite solution was about 3 g/L.The results show that purification efficiency was affected by catalyst addition,pH,experimental temperature,and sulfur capacity.The parameters effects on catalytic oxidation were studied,and the optimized conditions were that Fe3+ concentration 0.08 mg/L,reaction temperature 70°C,pH 9.0,with a absorption solution volume of 50 mL,a gas flow rate 200 mL/min,and H2S mass concentration of 1.58-2.02 mg/m3. 展开更多
关键词 liquid phase catalytic oxidation hydrogen sulfide rural biogas purification efficiency RARE-EARTH
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Inactivation of Protein Tyrosine Phosphatase 1B (PTP1B) Activity by the Aqueous Partition of Guava Leaf Extract
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作者 Wan-Jung Wu Wei-Li Yan +11 位作者 Shiou-Cherng Yu Gerry Gunawan Chien-Yih Lin Chih-Yan Huang Chia-Ting Chang Haw-Wen Chen Chong-Kuei Lii Alice L. Yu Ching-Chu Chen Yu-Ting Chung Jeng-Dau Tsai Henry J. Tsai 《Journal of Pharmacy and Pharmacology》 2018年第10期890-906,共17页
Guava leaf tea has been used as a folk medicine for treating hyperglycemic conditions in Asia and Africa. The hypoglycemic efficacy of guava leaf has been documented by many scientists in these regions, but the hypogl... Guava leaf tea has been used as a folk medicine for treating hyperglycemic conditions in Asia and Africa. The hypoglycemic efficacy of guava leaf has been documented by many scientists in these regions, but the hypoglycemic mechanism is poorly understood. Guava leaves were extracted with methanol and the crude extract was partitioned against hexane, ethyl acetate, and butanol in sequence. The leftover in water is defined as the aqueous partition. A second smaller batch was extracted with hot water directly. Oral glucose tolerance test was carried out on healthy mice instead of diabetic mice that lack endogenous insulin. Glucose uptake was examined with 3T3-L1 adipocytes. Oxidative effect on PTP1B (protein tyrosine phosphatase 1b) was carried out with real-time PTP1B enzymatic assay. The aqueous partition of guava leaf extract possesses a potent inhibitory effect on PTP1B enzymatic activity and this PTP1B inhibition is through a slow oxidative but reversible inactivation on the enzyme. The reversible inactivation would suggest guava leaf extract may augment PTP1B inhibition alongside the endogenous H2O2 which itself is induced by insulin. In addition, our study confirmed the hypoglycemic efficacy being associated with guava leaf and found the most effective molecules reside in the aqueous partition which is also less cytotoxic to Chinese hamster ovary cells when compared to other less polar partitions. The guava leaf extract can modulate insulin activity through a redox regulation on PP1B enzymatic activity. It is speculated that a compound similar to gallocatechin in the aqueous partition can reduce an oxygen molecule to hydrogen peroxide which in turn oxidizes the catalytic residue Cys in PTP1B. Therefore, the guava leaf tea can serve as a functional hypoglycemic drink that is suitable for either healthy or diabetic subjects. 展开更多
关键词 Guava leaf extract HYPOGLYCEMIC OXIDATIVE protein tyrosine phosphatase 1b slow inactivation.
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Study of Changes in Physiochemical Properties of Soil by the Addition of Cement
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作者 M. Ramzan A. Farooqi 《Journal of Environmental Science and Engineering》 2011年第3期323-332,共10页
The effect of cement on physiochemical properties of three types of soils i.e garden soil, agricultural soil and roadside soil was investigated. The ordinary Portland cement was used. The amount of cement added to soi... The effect of cement on physiochemical properties of three types of soils i.e garden soil, agricultural soil and roadside soil was investigated. The ordinary Portland cement was used. The amount of cement added to soil samples, as dry mass percentage was 20%. The results of analysis showed that the addition of cement is capable of bringing about changes in physiochemical properties of soil. The electrical conductivity and organic matter content in three soils get decreased by the addition of cement. While the pH, bulk density and water holding capacity of soils after the addition of cement gets increased. The soil found most suitable to be treated with cement was roadside soil. It was concluded that cement can be used to change the physiochemical properties of soil and this technique has great utility in improving the quality of problematic soils. 展开更多
关键词 Physiochemical properties soil-cement mixture problematic soils erosion.
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塘泥过厚 危害多多 被引量:1
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作者 周之武 《齐鲁渔业》 2003年第5期29-29,共1页
良好生态环境的养鱼池塘,塘底需要一定厚度的底泥,它对于调节池水肥度、酸碱度以及一些鱼类的藏匿和越冬等都有积极的作用。对于一般养殖鱼类而言,适宜的底泥厚度以10~15 cm为佳。但是,有不少养鱼户对此缺乏认识,池塘经过多年的使用也... 良好生态环境的养鱼池塘,塘底需要一定厚度的底泥,它对于调节池水肥度、酸碱度以及一些鱼类的藏匿和越冬等都有积极的作用。对于一般养殖鱼类而言,适宜的底泥厚度以10~15 cm为佳。但是,有不少养鱼户对此缺乏认识,池塘经过多年的使用也不清淤,底泥的厚度远远超过这一标准,有的达到0.5m以上,还有的甚至超过0.8 m。 展开更多
关键词 池塘养鱼 塘泥 危害 养殖水体有效体积 水质酸化 水质富营养 泛池
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Ultrasmall Ag nanoclusters anchored on NiCo-layered double hydroxide nanoarray for efficient electrooxidation of 5-hydroxymethylfurfural 被引量:2
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作者 Jing Jin Yingyan Fang +3 位作者 Tianyu Zhang Aijuan Han Bingqing Wang Junfeng Liu 《Science China Materials》 SCIE EI CAS CSCD 2022年第10期2704-2710,共7页
Electrochemical oxidation of 5-hydroxymethylfurfural(HMF)has shown promising prospects in producing highly valuable chemicals.Herein,we report the synthesis of ultrasmall Ag nanoclusters anchored on NiColayered double... Electrochemical oxidation of 5-hydroxymethylfurfural(HMF)has shown promising prospects in producing highly valuable chemicals.Herein,we report the synthesis of ultrasmall Ag nanoclusters anchored on NiColayered double hydroxide(NiCo-LDH)nanosheet arrays(Agn@NiCo-LDH)via a facile electrodeposition strategy.The prepared Agn@NiCo-LDH nanosheet arrays exhibit excellent electrocatalytic HMF oxidation performance with a current density of 10 mA cm^(−2) at 1.29 VRHE and the Faraday efficiency of nearly 100%for 2,5-furandicarboxylic acid production.This study offers an effective approach to rationally design nanoclusters to achieve high catalytic activity for sustainable energy conversion and production. 展开更多
关键词 ultrasmall Ag nanoclusters layered double hydroxides nanosheet array ELECTRODEPOSITION 5-hydroxymethylfurfural electrooxidation
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A rapid protein sample preparation method based on organic-aqueous microwave irradiation technique
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作者 Shuaibin Wu Hongfei Zhang +4 位作者 Kaiguang Yang Junfeng Ma Zhen Liang Lihua Zhang Yukui Zhang 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第3期526-531,共6页
Fast and efficient sample preparation methods are a prerequisite for protein identification in bottom-up proteomics. Here, an innovative microwave irradiation sample preparation method was developed based on an optimi... Fast and efficient sample preparation methods are a prerequisite for protein identification in bottom-up proteomics. Here, an innovative microwave irradiation sample preparation method was developed based on an optimized organic-aqueous solvent system for protein identification. Specifically, protein solutions containing high-concentration acetonitrile were subjected to 5 min microwave irradiation. After cooling down, trypsin was added and the digestion was performed with 30 s microwave irradiation, and the resulting peptides were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS). A shortened processing time of only 5.5 min is needed with this method(more than 12 h is necessary in the traditional overnight protein sample preparation). Moreover, due to the absence of urea and other chaotropic reagents, the digests can be readily identified by MALDI-TOF MS. When an assessment of this method was performed by digesting a model protein BSA, 69% ± 3% sequence coverage corresponding to 47 ± 3 peptides was obtained, which shows better protein identification than that from the standard overnight protein sample preparation method(51% ± 2% sequence coverage and 23 ± 1 peptides). Another model protein α-casein was used for the analysis of protein phosphorylation with the newly developed method that yielded 4 phosphopeptides with 8 phosphorylation sites, whereas 3 phosphopeptides with 2 phosphorylation sites were obtained from the traditional overnight approach. Moreover, the organic-aqueous microwave irradiation method provides effective digestion for proteins down to fmol. 展开更多
关键词 MALDI-TOF MS microwave organic-aqueous solvent protein identification DIGESTION
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Uranyl oxamate hydrates: hydrothermal synthesis, crystal structure, photophysical properties, and selective crystallization
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作者 Yubo Shu Weisheng Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第6期740-745,共6页
Presented here are two isostructural uranyl coordination polymers [UOe(EDO)(H2O)]· H2O (1) and [UO2(BDO)(H2O)]-2H2O (2) (EDO2---ethylene-1,2-dioxamate; BDO2 =butylene-1,2-dioxamate) with identical s... Presented here are two isostructural uranyl coordination polymers [UOe(EDO)(H2O)]· H2O (1) and [UO2(BDO)(H2O)]-2H2O (2) (EDO2---ethylene-1,2-dioxamate; BDO2 =butylene-1,2-dioxamate) with identical stepwise zigzag chain structure and distinct interchain hydrogen bonding interaction, prepared from hydrothermal reaction of DEEDO or DEBDO (DEEDO- diethyl ethylene-1,2-dioxamate; DEBDO--diethyl butylene-l,2-dioxamate) with uranyl ions. The monomeric uranyl-based fluorescence emissions of compounds 1 and 2 are red-shifted by about 6 and 5 nm respectively, compared to that of uranyl nitrate hexahydrate. Compound 1 has stronger emission than compound 2, but both their emissions exhibit triple-exponential decay. The photophysics of uranyl oxalate trihydrate was also investigated for comparison. The selective crystallization of compound 1 in alkaline solution was applied to the sequestration of uranyl ions, showing a kinetic preference. 展开更多
关键词 uranium oxamate hydrothermal synthesis PHOTOPHYSICS selective crystallization
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