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四元体系Li^+,K^+,Mg^(2+)/SO_4^(2-)—H_2O 25℃相关系和溶液物化性质的研究 被引量:14
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作者 房春晖 李冰 +2 位作者 李军 王庆忠 宋彭生 《化学学报》 SCIE CAS CSCD 北大核心 1994年第10期954-959,共6页
用等温溶解平衡法研究了四元体系Li^+,K^+,Mg^(2+)/So_4^(2-)-H_2O25℃溶解度,测定了饱和溶液的密度、粘度、折光率、pH和电导率等物化性质.四元体系相图由六条溶解度分枝线和五个结晶区构成,分别对应于原始组分和复盐Li_2SO_4·K_2... 用等温溶解平衡法研究了四元体系Li^+,K^+,Mg^(2+)/So_4^(2-)-H_2O25℃溶解度,测定了饱和溶液的密度、粘度、折光率、pH和电导率等物化性质.四元体系相图由六条溶解度分枝线和五个结晶区构成,分别对应于原始组分和复盐Li_2SO_4·K_2SO_4,K_2SO_4·MgSO_4·6H_2O,没有发现新的复盐或固溶体,也没有发生原始组分的脱水作用.用现代电解质溶液理论——Pitzer模型校验该体系的溶解度测定值,结果令人满意. 展开更多
关键词 水盐体系 相平衡 物化物质 P模型
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C_6H_8O_7·H_2O和LiC_6H_7O_7·H_2O单晶性质的研究 被引量:1
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作者 王继扬 李丽霞 +2 位作者 刘苏淮 王民 杨兆荷 《人工晶体学报》 EI CAS CSCD 1993年第4期366-370,共5页
本文报道了一水柠檬酸和一水柠檬酸氢锂晶体的生长外形、热性质、介电性质及激光喇曼光谱等的测试结果。
关键词 柠檬酸 柠檬酸锂单晶 物化物质
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Research on Geographical Indications and Cultural Heritage of Famous Tea in Hubei 被引量:1
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作者 孙志国 黄莉敏 +2 位作者 熊晚珍 王树婷 钟学斌 《Agricultural Science & Technology》 CAS 2012年第3期502-506,536,共6页
In the study, analysis was made on present situation and development measures of geographical indications and cultural heritage protection of famous teas in Hubei Province. In addition, 8 related suggestions were prop... In the study, analysis was made on present situation and development measures of geographical indications and cultural heritage protection of famous teas in Hubei Province. In addition, 8 related suggestions were proposed as well. 展开更多
关键词 TEA Geographical indication Cultural heritage Tangible cultural heritage Intangible cultural heritage Hubei Province
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Research status of carbonaceous matter in carbonaceous gold ores and bio-oxidation pretreatment 被引量:5
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作者 杨洪英 刘倩 +1 位作者 宋襄翎 董金奎 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3405-3411,共7页
Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanid... Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanide complex is robbed by adsorption of carbonaceous matter, which is similar to activated carbon in cyanide leaching of gold. The pretreatment methods of carbonaceous gold ores were introduced, including high temperature roasting, bio-oxidation, chemical oxidation, competitive adsorption, barrier inhibition and microwave roasting. Recently, bio-oxidation was developed rapidly due to its advantages such as mild conditions, simple processes, low energy consumption and friendly environment. The known microorganisms related with bio-oxidation pretreatment mainly are chemolithotroph bacteria such as Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirillum ferrooxidans. The researches on decomposing and passivating carbonaceous matter were commenced by Phanerochaete chrysosporium, Pseudomonadaceae and Streptomyces setonii. Finally, the main problems were analyzed and the application prospect of this technique was looked forward. 展开更多
关键词 carbonaceous gold ores carbonaceous matter PRETREATMENT bio-oxidization research status
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Biological Characteristics and Rumen Microorganisms of Gayal(Bos frontalis)in Yunnan Province 被引量:3
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作者 杨舒黎 苟潇 +3 位作者 冷静 毛华明 邓卫东 吴锡川 《Agricultural Science & Technology》 CAS 2011年第8期1234-1237,共4页
[Objective]The paper was to provide reference for further study and development of gayal(Bos frontalis).[Method]According to the research status at home and abroad,the biological characteristics and rumen microorgan... [Objective]The paper was to provide reference for further study and development of gayal(Bos frontalis).[Method]According to the research status at home and abroad,the biological characteristics and rumen microorganisms of gayal in Yunnan Province was studied.[Result]Gayal in Yunnan had typical body form and very good meat production performance,its muscle fiber diameter was significantly less than other kinds of cattle;the water holding ratio,muscle tenderness and muscle succulency were significantly higher than others;its amount,shape and structure of chromosome were different from yellow cattle(Bos taurus)and wild cattle(Bos gaurus),and the amounts of those chromosomes(2n)were 58,60 and 56,respectively.It could create hybrid with yellow cattle;the gayal's special diet was bamboo,its in vitro dry matter digestibility(IVDMD)on various crude forage was significantly higher than yellow cattle in Yunnan;the viable bacteria and cellulolytic bacteria in rumen were 4.51×109 and 1.63×109 CFU/ml,which was significantly higher than yellow cattle in Yunnan,its dominant bacteria in rumen mainly was cellulolytic bacteria.[Conclusion]Gayal not only had high academic value,but also had a great development value. 展开更多
关键词 Gayal(Bos frontalis)in Yunnan Meat quality Genetic diversity Nutrient digestibility Rumen microorganism
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Design of Integration Grinder with Air-induced Discharging Device
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作者 王明友 宋卫东 +2 位作者 李尚昆 吴金姬 王教领 《Agricultural Science & Technology》 CAS 2016年第3期724-727,共4页
To meet the large-scale smashing production of soft straw and hard straw with high fiber materials and overcome the shortcomings of single-mission cutter and shredder, a straw grinder with air-induced discharging devi... To meet the large-scale smashing production of soft straw and hard straw with high fiber materials and overcome the shortcomings of single-mission cutter and shredder, a straw grinder with air-induced discharging device was developed, which realized the force feeding of hard straws with high fiber. The results showed that soft straw could be directly fed into the smashing device without cutting with the average efficiency of 1.27 kg/h and electricity consumption o per ton of 32.0 k W·h.The hard straw with high fiber should be first fed into the shredding device with force feeding roll to cut and then grinded, for which the efficiency average was 0.67kg/h and electricity consumption per ton was 60.5 k W·h. The machine was stable,safe and reliable with strong adaptability of materials and no-dust operating environment, which satisfied the design requirements. 展开更多
关键词 BIOMASS MATERIAL Grind INTEGRATION
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Hydrogen Production From Crude Bio-oil and Biomass Char by Electrochemical Catalytic Reforming
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作者 李兴龙 宁坤 +1 位作者 袁丽霞 李全新 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第4期477-483,I0004,共8页
We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield... We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield reached 110.9 g H2/kg dry biomass. The product gas was a mixed gas containing 72%H2, 26%CO2, 1.9%CO, and a trace amount of CH4. It was observed that adding biomass char (a by-product of pyrolysis of biomass) could remarkably increase the absolute H2 yield (about 20%-50%). The higher reforming temperature could enhance the steam reforming reaction of organic compounds in crude bio-oil and the reaction of CO and H20. In addition, the CuZn-Al2O3 catalyst in the water-gas shift bed could also increase the absolute H2 yield via shifting CO to CO2. 展开更多
关键词 Hydrogen BIO-OIL Biomass char Ni-Al2O3 catalyst CuZn-AI203 catalyst Electro chemical catalytic reforming
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Geochemical characteristics of the fluid inclusions in the Gangxi Fault Belt, Huanghua Depression, Bohai Bay Basin, China 被引量:2
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作者 DING Wei-wei DAI Jin-xing +1 位作者 CHU Feng-you HAN Xi-qiu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第7期1011-1020,共10页
We studied the geochemical characteristics of the fluid inclusions in the Ordovician carbonates and the Oligocene Shahejie Formation sandstones from 15 wells in the Gangxi Fault Belt, Huanghua Depression. The fluid in... We studied the geochemical characteristics of the fluid inclusions in the Ordovician carbonates and the Oligocene Shahejie Formation sandstones from 15 wells in the Gangxi Fault Belt, Huanghua Depression. The fluid inclusions are all sec- ondary with gas/liquid ratio of 5%~10%. Base on Raman they are mainly composed of H2O, CO2 and CH4. The homogenization temperatures, combined with burial and geothermal history of the host rock, indicate that the fluid flows in the Shahejie Formation and the Ordovician carbonates were trapped in Neocene. Using a VG5400 mass spectrometer, the helium isotopic compositions were analyzed. Interpretation of results suggested a significant amount of mantle-derived helium mainly accumulating in the intersections of the NWW trending Xuzhuangzi and NE trending Gangxi faults. The maturity of hydrocarbon decreases from the intersection to the outside pointing out that the fluid related to the NWW trending Xuzhuangzi and NE trending Gangxi faults. These factors implied the fluid inclusions have a close relationship to the local tectonic setting. Gangxi Fault Belt experienced intensive Neo-tectonic activities in Cenozoic. Widespread faulted-depressions and strong volcanic eruptions manifested its tec- tonic status of extensional stress field. Mantle uplift caused the movement of magma that carried mantle-derived gases and deep heat flows, the deep-rooted tension faults provided the passages for the gases and heat flows to shallow crust levels. 展开更多
关键词 Gangxi Fault Belt Fluid inclusion Composition MANTLE-DERIVED Maturity Local tectonic setting
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Extraction and PTP1B inhibitory activity of bromophenols from the marine red alga Symphyocladia latiuscula 被引量:2
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作者 刘旭 李晓明 +4 位作者 高立信 崔传明 李春顺 李佳 王斌贵 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期686-690,共5页
Previously, we had characterized several structurally interesting brominated phenols from the marine red alga Symphyocladia latiuscula collected from various sites. However, Phytochemical investigations on this specie... Previously, we had characterized several structurally interesting brominated phenols from the marine red alga Symphyocladia latiuscula collected from various sites. However, Phytochemical investigations on this species collected from the Weihai coastline of Shandong Province remains blank. Therefore, we characterized the chemical constituents of individuals of this species collected from the region. Eight bromophenols were isolated and identified. Using detailed spectroscopic techniques and comparisons with published data, these compounds were identified as 2,3-dibromo-4,5-dihydroxybenzyl methyl ether (1), 3,5-dibromo-4-hydroxybenzoic acid (2), 2,3,6-tribromo-4,5-dihydroxymethylbenzene (3), 2,3,6-tribromo-4,5-dihydroxybenzaldehyde (4), 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether (5), bis(2,3,6-tribromo-4,5-dihydroxyphenyl)methane (6), 1,2-bis(2,3,6-tribromo-4,5-dihydroxyphenyl)-ethane (7), and 1-(2,3,6-tribromo-4,5-dihydroxybenzyl)-pyrrolidin-2-one (8). Among these compounds, 1 and 2 were isolated for the first time from S. latiuscula. Each compound was evaluated on the ability to inhibit protein tyrosine phosphatase 1B (PTP1B), which is a potential therapeutic target in the treatment of type 2 diabetes. Bromophenols 5, 6, and 7 showed strong activities with IC50 values of 3.9, 4.3, and 3.5 μmol/L, respectively. This study provides further evidence that bromophenols are predominant among the chemical constituents of Symphyocladia, and that some of these compounds may be candidates for the development of anti-diabetes drugs. 展开更多
关键词 marine alga RHODOMELACEAE Symphyocladia latiuscula bromophenol protein tyrosine phosphatase 1B (PTP1B)
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Protein and non-protein sulfhydryls and disulfides in gastric mucosa and liver after gastrotoxic chemicals and sucralfate: Possible new targets of pharmacologic agents 被引量:6
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作者 Lajos Nagy Miki Nagata Sandor Szabo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第14期2053-2060,共8页
AIM: To investigate the role of major non-protein and protein sulfhydryls and disulfides in chemically induced gastric hemorrhagic mucosal lesions (HML) and the mechanism of gastroprotective effect of sucralfate.ME... AIM: To investigate the role of major non-protein and protein sulfhydryls and disulfides in chemically induced gastric hemorrhagic mucosal lesions (HML) and the mechanism of gastroprotective effect of sucralfate.METHODS: Rats were given 1 mL of 75% ethanol, 25%NaCl, 0.6 mol/L HCI, 0.2 mol/L NaOH or 1% ammonia solutions intragastrically (i.g.) and sacrificed 1, 3, 6 or 12 min later. Total (reduced and oxidized) glutathione (GSH + GSSG), glutathione disulfide (GSSG), protein free sulfhydryls (PSH), protein-glutathione mixed disulfides (PSSG) and protein cystine disulfides (PSSP) were measured in gastric mucosa and liver.RESULTS: Reduced glutathione (GSH) was depleted in the gastric mucosa after ethanol, HCI or NaCl exposure,while oxidized glutathione (GSSG) concentrations increased, except by HCI and NaOH exposure. Decreased levels of PSH after exposure to ethanol were observed,NaCl or NaOH while the total protein disulfides were increased. Ratios of reduced to oxidized glutathione or sulfhydrils to disulfides were decreased by all chemicals.No changes in thiol homeostasis were detected in the liver after i.g. abbreviation should be spelled out the first time here administration of ethanol. Sucralfate increased the concentrations of GSH and PSH and prevented the ethanol-induced changes in gastric mucosal thiol concentrations.CONCLUSION: Our modified methods are now suitable for direct measurements of major protein and nonprotein thiols/disulfides in the gastric mucosa or liver.A common element in the pathogenesis of chemically induced HML and in the mechanism of gastroprotective drugs seems to be the decreased ratios of reduced and oxidized glutathione as well as protein sulfhydryls and disulfides. 展开更多
关键词 Non-protein and protein thiol Gastricmucosal injury GASTROPROTECTION Sucralfate
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Catalytic cracking mechanisms of tar model compounds 被引量:1
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作者 陈波 时章明 +1 位作者 蒋绍坚 田红 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3100-3107,共8页
B3LYP/6-31G(d,p) method was used to investigate the catalytic cracking mechanism of biomass tar model compound.Phenol,toluene and benzene were selected as the tar model compounds and CaO was selected as the catalyst.T... B3LYP/6-31G(d,p) method was used to investigate the catalytic cracking mechanism of biomass tar model compound.Phenol,toluene and benzene were selected as the tar model compounds and CaO was selected as the catalyst.The pathways of tar compound radical absorbed by CaO were determined firstly through comparing enthalpy changes of the absorption,and then Mulliken population changes were analyzed.The results show that the absorption of tar model compound radical and CaO is an exothermic reaction.Formation of C—O—Ca is more easily than that of C—Ca—O and formation of Caromatic—Caromatic—Ca—O is more easily than that of Caromatic—C(O)—Ca—O.The C—C bond Mulliken populations in tar model compound radicals are reduced by 11.9%,10.5% and 15.5% in the case of a hydrogen atom removed,and those are 15.7%,14.3% and 16.3% in the case of two hydrogen atoms removed through the absorption of CaO.Catalytic ability of CaO acting on the tar model compound is in an order of phenol>benzene>toluene. 展开更多
关键词 BIOMASS tar model compounds catalytic cracking MECHANISMS quantum chemistry
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Stability Studies on the Aqueous Extract of the Fresh Leaves of Combretum Micranthum G. Don Used as Antibacterial Agent 被引量:1
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作者 Uduma Eke Osonwa Chukwuebuka Emmanuel Umeyor +2 位作者 Uduak Victor Okon Emmanuel Maduabuchi Uronnachi Calistus Dozie Nwakile 《Journal of Chemistry and Chemical Engineering》 2012年第5期417-424,共8页
The fresh leaves of Combretum micranthum were harvested during the rainy season in Akwa Ibom State, washed and subjected to extraction by maceration in distilled water. Concentration was done with a rotary evaporator.... The fresh leaves of Combretum micranthum were harvested during the rainy season in Akwa Ibom State, washed and subjected to extraction by maceration in distilled water. Concentration was done with a rotary evaporator. The extracts were tested for content of the following phytochemicals using standard methods: alkaloids, saponins, tannins, anthraquinones, cardiac glycosides, flavonoids and steroids. Antibacterial sensitivity test of the extract was carried out on S. aureus, B. subtilis and E. coli using agar well diffusion method and Ampiclox as control. The effect of storage time of the extract on its antibacterial activity was determined after the extract was kept at room temperature for 1 h, 24 h, 48 h and 72 h, respectively. Preparations of 200 mg/mL of the aqueous extract were made with additives as follows: (a) no additive; (b) methyl paraben (0.3%); (c) propyl paraben (0.3%); (d) sodium metabisulfite (0.01%); (e) A combination of methyl paraben (0.3%) and propyl paraben (0.3%); (f) A combination of methyl paraben (0.3%), propyl paraben (0.3%) and sodium metabisulfite (0.01%). A visual observation of the stabilized preparations was employed on daily basis for 30 days. Phytochemical analyses on the aqueous extract of the fresh leaves showed the absence of alkaloids, anthraquinones and flavonoids. Saponins, cardiac glycosides and steroids were present in moderate amounts and there was abundance of tannins. The extract had similar effect on both S. aureus and E. coli cultures but activity was very low with B. subtilis. When S. aureus activity increased with time of storage up to 48 hours, thereafter the activity started reducing. However, the activity of E. coli continued to increase with time (within the study period). Thus, it appears reasonable to store the extract for at least 48 hours before the use for enhanced activity. 展开更多
关键词 Combretum micranthum fresh leaves aqueous extract ANTIBACTERIAL stability.
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Extracellular vesicle–based drug delivery system boosts phytochemicals’therapeutic effect for neurodegenerative diseases 被引量:1
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作者 Zhenzhu Zhu Liuyue Liao Hongzhi Qiao 《Acupuncture and Herbal Medicine》 2022年第4期229-239,共11页
Neurodegenerative diseases(NDs)are a major threat to the elderly,and efficient therapy is rarely available.A group of phytochemicals has been shown to ameliorate NDs;however,poor stability,low bioavailability,and redu... Neurodegenerative diseases(NDs)are a major threat to the elderly,and efficient therapy is rarely available.A group of phytochemicals has been shown to ameliorate NDs;however,poor stability,low bioavailability,and reduced drug accumulation in brain tissue limit their application in NDs.Therefore,a targeted drug delivery system is a feasible treatment strategy for NDs.Extracellular vesicles(EVs)possess many favorable bioactivities and are excellent carriers for targeting brain tissue.This review summarizes EVs as novel phytochemical carriers in ND therapy.First,we discuss the current challenges of ND therapy and the therapeutic effects of phytochemicals for NDs.Second,we highlight the ability of EVs to cross the blood-brain barrier and act as drug carriers to enhance the therapeutic efficacy of drugs for NDs.Finally,encapsulation strategies for phytochemicals in EVs are particularly reviewed,as they are critical for obtaining high loading efficacy and stable drug delivery systems.This review provides new insights into EV-based drug delivery systems for improving the therapeutic effect of phytochemicals for ND treatment.Therefore,the release rate and pharmacokinetics of phytochemicals should be well controlled to ensure the therapeutic efficacy of phytochemical-loaded EVs in the brain. 展开更多
关键词 BIOAVAILABILITY Brain-targeting Extracellular vesicle-based drug delivery system Neurodegenerative diseases PHYTOCHEMICALS
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Bioleaching of chalcopyrite by mixed culture of moderately thermophilic microorganisms 被引量:8
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作者 邬长斌 曾伟民 +4 位作者 周洪波 符波 黄菊芳 邱冠周 王淀佐 《Journal of Central South University of Technology》 EI 2007年第4期474-478,共5页
A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages(AMDs)samples collected from several sulphide mines in China,and the bioleaching of chalcopyrite was conducted both in sha... A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages(AMDs)samples collected from several sulphide mines in China,and the bioleaching of chalcopyrite was conducted both in shake flask and bioreactor.The results show that in the shake flask,the mixture can tolerate 50 g/L chalcopyrite after being acclimated to gradually increased concentrations of chalcopyrite.The copper extraction increases obviously in bioleaching of chalcopyrite with moderately thermophilic microorganisms supplemented with 0.4 g/L yeast extract at 180 r/min,74% copper can be extracted in the pulp of 50 g/L chalcopyrite after 20 d.Compared with copper extractions of mesophilic culture,unacclimated culture and acclimated culture without addition of yeast extract,that of accliniated culture with addition of yeast extract is increased by 53%,44% and 16%,respectively.In a completely stirred tank reactor,the mass fraction of copper and total iron extraction reach up to 81% and 56%,respectively.The results also indicate that it is necessary to add a large amount of acid to the pulp to extract copper from chalcopyrite effectively. 展开更多
关键词 BIOLEACHING moderately thermophilic microorganisms ACCLIMATION CHALCOPYRITE shake flask experiment stirred tank reactor
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Physicochemical properties and heavy metals leachability of fly ash from coal-fired power plant 被引量:5
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作者 Xiang Wei Han Baoping +1 位作者 Zhou Dong Nzihou Ange 《International Journal of Mining Science and Technology》 SCIE EI 2012年第3期405-409,共5页
The physicochemical properties of fly ash from two kinds of coal-fired power plants were studied. Three aspects were examined: the micro-morphology, the mineral composition and the content of heavy metals. The result... The physicochemical properties of fly ash from two kinds of coal-fired power plants were studied. Three aspects were examined: the micro-morphology, the mineral composition and the content of heavy metals. The results show that the fly ash from plants using a circulating fluidized bed are more irregular par- ticles, while the particles from the plants using a pulverized coal-fired boiler are mainly spherical in shape. Quartz and mullite are the main crystalline phases in the ash. Clearly, both the technology and the coal used by a power plant can influence the mineral composition of the ash. The mineral composition of fly ash from a circulating fiuidized bed is more complex than that from a pulverized coal-fired boiler. The quantity of elements found in the fly ash is greater than that found in the bottom ash for the same plant. Heavy metals are likely to be enriched in the fly ash. Heavy metal leachability was studied using two leaching methods. The results indicate that most of the heavy metals that leached during either batch leaching or column leaching experiments did not exceed the related maximum concentration standards. But Ni concentrations in the leachates from both batch and column tests exceed the standard. The highest excess rates in both tests were 572~ and 497~, which levels might threaten the environment. 展开更多
关键词 Fly ashPhysicochemical propertyLeachabilityHeavy metal
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Paddy Soil Stability and Mechanical Properties as Affected by Long-Term Application of Chemical Fertilizer and Animal Manure in Subtropical China 被引量:33
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作者 LI Jiang-Tao ZHANG Bin 《Pedosphere》 SCIE CAS CSCD 2007年第5期568-579,共12页
Wet stability, penetration resistance (PR), and tensile strength (TS) of paddy soils under a fertilization experiment for 22 years were determined to elucidate the function of soil organic matter in paddy soil sta... Wet stability, penetration resistance (PR), and tensile strength (TS) of paddy soils under a fertilization experiment for 22 years were determined to elucidate the function of soil organic matter in paddy soil stabilization. The treatments included no fertilization (CK), normal chemical fertilization (NPK), double the NPK application rates (2NPK), and NPK mixed with organic manure (NPK+OM). Compared with CK, Fertilization increased soil organic carbon (SOC) and soil porosity. The results of soil aggregate fragmentation degree (SAFD) showed that fast wetting by water was the key fragmentation mechanism. Among the treatments, the NPK+OM treatment had the largest size of water-stable aggregates and greatest normal mean weight diameter (NMWD) (P ≤ 0.05), but the lowest PR and TS in both cultivated horizon (Ap) and plow pan. The CK and 2NPK treatments were measured with PR 〉 2.0 MPa and friability index 〈 0.20, respectively, in the Ap horizon, suggesting that the soils was mechanically unfavourable to root growth and tillage. In the plow pan, the fertilization treatments had greater TS and PR than in CK. TS and PR of the tested soil aggregates were negatively correlated to SOC content and soil porosity. This study suggested that chemical fertilization could cause deterioration of mechanical properties while application of organic manure could improve soil stability and mechanical properties. 展开更多
关键词 soil aggregate stability chemical fertilization organic matter penetration resistance tensile strength
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Bioleaching of a kind of alkaline mixed copper oxide and sulphide mineral 被引量:2
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作者 黄明清 吴爱祥 《Journal of Chongqing University》 CAS 2010年第4期177-184,共8页
We conducted two-stage acidification-bioleaching experiments to probe the feasibility of bioleaching for a kind of mixed alkaline copper oxide and sulphide mineral. We used the uniform design method for data analysis ... We conducted two-stage acidification-bioleaching experiments to probe the feasibility of bioleaching for a kind of mixed alkaline copper oxide and sulphide mineral. We used the uniform design method for data analysis and experimental optimization, with initial pH value, pulp density, inoculation of bacteria and ferrous iron concentration selected as the influential factors. Polynomial regression shows that the four factors sequentially influence the copper recovery by 14.430%, 8.555%, 1.982% and 3.895%. Acid equilibrium in the bioleaching system is mainly influenced by alkaline gangue content, chemical reactions and bacterial activity. A maximal portion of refractory copper extracted reaches 71.08%. The dynamic analysis of copper recovery indicates that bioleaching goes through a lag leaching phase, prime leaching phase and leaching stationary phase corresponding to the growth phases of bacteria. Compared with the predicted value of 80.87%, the confirmatory experiment observes a 78.21% copper recovery under the optimal conditions of pH of 1.5, pulp density of 5%, bacteria inoculation of 30% and initial ferrous iron concentration of 9 g L-1. Results suggest that bioleaching is technically feasible to improving total copper recovery. 展开更多
关键词 alkaline mixed copper oxide and sulphide mineral BIOLEACHING uniform design copper recovery acid equilibrium
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Removal and transformation of organic matter during soil-aquifer treatment 被引量:1
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作者 ZHAO Qing-liang XUE Shuang +1 位作者 YOU Shi-jie WANG Li-na 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第5期712-718,共7页
This study investigated the removal and transformation of organic matter through laboratory-scale soil-aquifer treatment (SAT) soil columns over a 110-day period. Reductions in total organic carbon (TOC), dissolved or... This study investigated the removal and transformation of organic matter through laboratory-scale soil-aquifer treatment (SAT) soil columns over a 110-day period. Reductions in total organic carbon (TOC), dissolved organic carbon (DOC), biodegradable dissolved organic carbon (BDOC), nonbiodegradable dissolved organic carbon (NBDOC) and absorbance of ul-traviolet light at 254 nm (UV-254) averaged 71.46%, 68.05%, 99.31%, 33.27% and 38.96% across the soil columns, respectively. DOC/TOC ratios increased slightly with depth while BDOC/DOC ratios showed a converse trend. DOC exiting the soil-column system contained only a very small biodegradable fraction. SAT decreased the concentration of DOC present in feed water but increased its aromaticity, as indicated by specific ultraviolet light absorbance (SUVA), which increased by 50%~115% across the soil columns, indicating preferential removal of non-aromatic DOC during SAT. Overall, laboratory-scale SAT reduced triha-lomethane formation potential (THMFP), although specific THMFP increased. THMFP reduction was dominated by removal in chloroform. All samples exhibited a common general relationship with respect to weight: chloroform>dichlorobromomethane >dibromochloromethane>bromoform. 展开更多
关键词 Soil-aquifer treatment (SAT) Organic matter Dissolved organic matter Trihalomethane formation potential Bio-degradable dissolved organic carbon (BDOC) Specific trihalomethane formation potential
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Effect of Short Chain Alcohols upon Viscosity of TTAB Solution 被引量:1
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作者 Yun-fei Yan Hua-zhen Li +3 位作者 Hai-yang Yang Jia-sheng Qian Ping-ping Zhu Ping-sheng He 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第2期169-173,共5页
The effect of ethanol (C2H5OH), propanol (C3H7OH), and butanol (C4H9OH) upon the viscosity of tetradecyltrimethylammonium bromide (TTAB) solution in the presence or absence of KBr at 30℃was investigated, wher... The effect of ethanol (C2H5OH), propanol (C3H7OH), and butanol (C4H9OH) upon the viscosity of tetradecyltrimethylammonium bromide (TTAB) solution in the presence or absence of KBr at 30℃was investigated, where the surfactant concentration CS is kept constant. In the absence of KBr, the relative viscosity ηr of TTAB solution increases linearly with the alcohol concentration CA, indicating that the alcohols do not promote micelle formation of TTAB. In the presence of KBr, ηr linearly decreases with CA for C2H5OH, but it exhibits a maximum with increasing CA for C3H7OH or C4H9OH. The facts reveal that C2H5OH or C4H9OH promotes the micelle formation of TTAB. A possible explanation is that the hydrophobicity of the mieellar interior is enhanced by KBr, so that C2H5OH or C4H9OH can dissolve in micelle and promotes micelle formation. In the presence of KCl, which is less efficient in promoting the micelle formation of cationic surfactant, both C3H7OH and C4H9OH have only a slight effect on the micelle formation. In contrast, due to the hydrophilicity, C2H5OH cannot dissolve in micelles in the presence of KBr or KCl. 展开更多
关键词 Relative viscosity Cationic surfactant Organic additive Hydrophobic interaction
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Leaf choice in black-and-white snub-nosed monkeys Rhinopithecus bieti is related to the physical and chemical properties of leaves 被引量:6
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作者 Zhipang HUANG Sheng HUO +2 位作者 Shuguo YANG Liangwei CUI Wen XIAO 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第6期643-649,共7页
To understand the effects of the chemical and physical properties of plant leaves on food choice in Rhinopithecus bieti, we collected mature leaves of nine food and five non-food plant species at the southernmost part... To understand the effects of the chemical and physical properties of plant leaves on food choice in Rhinopithecus bieti, we collected mature leaves of nine food and five non-food plant species at the southernmost part of the species's range. Chemical properties such as fat, ash, crude protein (CP), total phenolics (TP), and fiber content including neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin, celluloses and hemicelluloses, and physical toughness were measured. R. bieti tended to choose leaves with lower fiber content, higher ash, a higher ratio of CP/ADF, and lower toughness. No difference was found for fat, crude protein, total phenolics, hemicelluloses and lignin between food and non-food leaves. Even though the ratio of CP/ADF is generally regarded as a good indicator for colobine food choice, the difference in the ratio of CP/ADF between food and non-food leaves was only the result of differences in ADE Since positive correlations were found between ADF and tough- ness from all leaves (both food and non-food species), and toughness of leaves was likely easier for R. bieti to sense than fiber content via mastication, the toughness of leaves may function as a predictor of food choice in this species [Current Zoology 56 (6) 643-49, 2010]. 展开更多
关键词 Rhinopithecus bieti Diet selection Protein-to-fiber ratio TOUGHNESS Mt. Longma YUNNAN
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