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Effect of Saline Water on Soil Acidity, Alkalinity and Nutrients Leaching in Sandy Loamy Soil in Rwamagana Bella Flower Farm, Rwanda
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作者 Abel Mwubahaman Wali Umaru Garba +3 位作者 Hussein Bizimana Jean de Dieu Bazimenyera Eric Derrick Bugenimana Jean Nepomuscene Nsengiyumva 《Agricultural Sciences》 2024年第1期15-35,共21页
The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific consideration... The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific considerations and limitations. One way to decrease undesirable effects of sodic waters on the physical and chemical properties of soils is to apply organic and chemical amendments within the soil. This study aimed to assess the effectiveness of saline water on soil acidity, alkalinity and nutrients leaching in sandy loamy soil at Bella flower farm, in Rwamagana District, Rwanda. The water used was from the Muhazi Lake which is classified as Class I (Saline water quality). Column leaching experiments using treated soils were then conducted under saturated conditions. The soil under experimental was first analyzed for its textural classification, soil properties and is classified as sandy loamy soil. The t-test was taken at 1%, 5% and 10% levels of statistical significance compared to control soil. The results indicated that the application of saline water to soils caused an increase in some soil nutrients like increase of Phosphorus (P), Potassium (K<sup>+</sup>), Magnesium (Mg2<sup>+</sup>), Sulphur (S), CN ratio and Sodium (Na<sup>+</sup>) and decreased soil texture, physical and chemical properties and remained soil nutrients. Consequently, the intensive addition of saline water leachates to soil in PVC pipes led to decreased of soil EC through leaching and a raiser Soluble Sodium Percentage (SSP). The rate of saline water application affected the increase accumulation of SAR and Na% in the top soil layers. The study indicated that saline water is an inefficient amendment for sandy soil with saline water irrigation. The study recommends further studies with similar topic with saline water irrigation, as it accentuated the alkalinity levels. 展开更多
关键词 NUTRIENTS LEACHING Saline Water Soil acidity Soil alkalinity
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Titratable Acidity and Alkalinity of Red Soil Surfaces
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作者 SHAOZONG-CHEN HEQUN 《Pedosphere》 SCIE CAS CSCD 1993年第2期107-117,共11页
The surfaces of red soils have an apparent amphoteric character,carrying titratable acidity and titratable alkalinity simultaneously.The titratable acidity arises from deprotonation of hydroxyl groups of hydrous oxide... The surfaces of red soils have an apparent amphoteric character,carrying titratable acidity and titratable alkalinity simultaneously.The titratable acidity arises from deprotonation of hydroxyl groups of hydrous oxide-type surfaces and dissociation of weak-acid functional groups of soil organic matter,while the titratable alkalinity is derived from release of hydroxyl groups of hydrous oxide-type surfaces.The titratable acidity and titratable alkalinity mainly depended on the composition and content of iron and aluminum oxides in the soils.The results showed that the titratable acidity and titratable alkalinity were in significantly positive correlation not only with the content of amorphous aluminum oxide(Alo) and iron oxide(Feo) extracted with acid ammonium oxalate solution,free iron oxide(Fed) extracted with sodium dithionite-citrate-bicarbonate(DCB) and clays,but also with the zero point of charge (ZPC) of the samples.Organic matter made an important contribution to the titratable acidity.the titratable alkalinity was closely correlated with the amount of fluoride ions adsorbed.The titratable acidity and titratable alkalinity of red soils were influenced by parent materials,being in the order of red soil derived from basalt> that from tuff> that from granite.The titratable acidity and titratable alkalinity ware closely related with origination of the variable charges of red soils,and to a certain extent were responsible for variable negative and positive charges of the soils. 展开更多
关键词 红壤 可滴定酸度 可滴定碱度 表面电荷 氟化物 吸附作用
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Comparison of acid-detergent lignin,alkaline-peroxide lignin,and acid-detergent insoluble ash as internal markers for predicting fecal output and digestibility by cattle offered bermudagrass hays of varying nutrient composition
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作者 Juvenal Kanani Dirk Philipp +6 位作者 Kenneth P Coffey Elizabeth B Kegley Charles P West Shane Gadberry John Jennings Ashley N Young Robert T Rhein 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第3期310-317,共8页
Background: The potential for acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict fecal output (FO) and dry matter digestibility (DMD) by cattle o... Background: The potential for acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict fecal output (FO) and dry matter digestibility (DMD) by cattle offered bermudagrass [Cynodon doctylon (L) Pers.] hays of different qualities was evaluated. Eight ruminally cannulated cows (594 ± 35.5 kg) were allocated randomly to 4 hay diets: low (L), medium low (ML), medium high (MH), and high (H) crude protein (CP) concentration (79, 111,131, and 164 g CP/kg on a DM basis, respectively). Diets were offered in 3 periods with 2 diet replicates per period and were rotated across cows between periods. Cows were individually fed 20 g DM/kg of body weight in equal feedings at 08:00 and 16:00 h for a 10-d adaptation followed by a 5-d total fecal collection. Actual DM intake (DMI), DMD, and FO were determined based on hay offered, ort, and feces excreted. These components were then analyzed for ADL, APL, and ADIA concentration to determine marker recovery and marker-based estimates of FO and DMD. Results: Forage DMI was affected by diet (P = 0.02), and DMI from MH and H was greater (P 〈 0.05) than from L. Apparent DMD tended (P = 0.08) to differ among diets while FO (P = 0.20) was not affected by diet treatments. Average ADL recovery (1.16) was greater (P 〈 0.05) than that of ADIA (1.03) and APL (1.06), but ADIA and APL did not differ (P = 0.42). Estimates of FO and DMD derived using APL and ADIA were not different (P≥0.05) from total fecal collection while those using ADL differed (P 〈 0.05). There was no diet by marker interaction (P≥ 0.22) for either FO or DMD. Conclusion: Acid-detergent insoluble ash and APL accurately predicted FO and DMD of cattle fed bermudagrass hay of varying nutrient composition. These internal markers may facilitate studies involving large numbers of animals and forages. Results from such studies may be used to develop improved equations to predict energy values of forages based on the relationship of dietary components to digestibility across a wide range of forages. 展开更多
关键词 acid-detergent insoluble ash alkaline-peroxide lignin BERMUDAGRASS Cattle DIGESTIBILity Marker
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Effects of deep alkaline and acidic fluids on reservoir developed in fault belt of saline lacustrine basin
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作者 Lei-Lei Yang Xin-Wei Li +4 位作者 Guo Wei Yi-Dan Liu Qin-Gong Zhuo Zhi-Chao Yu Zhi-Ye Gao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期776-786,共11页
Through the long development processes of reservoir sedimentation and diagenesis, acidic and alkaline fluids play key roles in controlling deep reservoir development. However, the ways in which deep fluids control and... Through the long development processes of reservoir sedimentation and diagenesis, acidic and alkaline fluids play key roles in controlling deep reservoir development. However, the ways in which deep fluids control and transform the reservoir under complex fault conditions remain unclear. In this study, a 2D model was established based on a typical sub-salt to intra-salt vertical profile in the Qaidam Basin, China. Based on measured data, multiphase flow reaction and solute transport simulation technology were used to analyze fluids flow and migration in the intra-salt and sub-salt reservoirs, determine the mineral dissolution, precipitation, and transformation in the reservoir caused by the deep fluids, and calculate the changes in reservoir porosity. Results show that deep fluid migrates preferentially along dominant channels and triggers a series of fluid–rock chemical reactions. In the first stage, a large amount of anhydrite precipitated in the fault as a result of upward migration of deep saline fluid, resulting in the formation of anhydrite veins and blockage at the base of the fault. In the second stage, organic acids caused minerals dissolution and a vertical channel was opened in previously blocked area, which promoted continuous upward migration of organic acids and the formation of secondary pores. This study clarifies the transformative effects of deep alkaline and acidic fluids on the reservoir. Moreover, the important fluid transport role of faults and their effect on reservoir development were determined. 展开更多
关键词 Saline lacustrine basin alkaline and acidic fluids Fault-belt reservoir Mineral transformation Physical conditions
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Alleviation of Soil Acidity and Aluminium Phytotoxicityin Acid Soils by Using Alkaline-Stabilised Biosolids 被引量:6
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作者 LUOYONGMING P.CHRISTIE 《Pedosphere》 SCIE CAS CSCD 2002年第2期185-188,共4页
A pot experiment was catried out to study alleviation of soil acidity and Al toxicity by applying analkaline-stabilised sewage sludge product (biosolids) to an acid clay sandy loam (pH 5.7) and a strongly acidsandy lo... A pot experiment was catried out to study alleviation of soil acidity and Al toxicity by applying analkaline-stabilised sewage sludge product (biosolids) to an acid clay sandy loam (pH 5.7) and a strongly acidsandy loam (pH 4.5). Barley (Hondeum vulgare L. cv. Forrester) was used as a test crop and was grownin the sewage sludge-amended (33.5 t sludge DM ha-1) and unamended soils. The results showed that thealka1ine biosloids increased soil pH from 5.7 to 6.9 for the clay sandy loam and from 4.5 to 6.0 for the sandyloam. The sludge product decreased KCl-extractable Al from 0.1 to 0.0 cmol kg-1 for the former soil andfrom 4.0 to 0.1 cmol kg-1 for the latter soil. As a result, barley plants grew much better and grain yieldincreased greatly in the amended treatments compared with the unamended controls. These observationsindicate that alkaline-stabilised biosolids can be used as a liming material for remedying Al phytotoxicity instrongly acid soils by increasing soil pH and lowering 展开更多
关键词 酸性土壤 酸度 土壤改良
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The Electrodeposition of Rhenium in Alkaline and Acidic Elektrolytes 被引量:1
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作者 Elza Salakhova Vusala Majidzade Firuza Novruzova Parvana Kalantarova Ramila Husevnova 《Journal of Chemistry and Chemical Engineering》 2012年第5期489-494,共6页
关键词 酸性电解液 碱性 极化曲线 化学循环 电沉积过程 电解质 溶液酸度
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Effect of noise exposure(85 dB) on testicular adrenocortical steroidogenic key enzymes, acid and alkaline phosphatase activities of sex organs in mature albino rats
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作者 Debidas Ghosh, Sampa Ghosh, Sandip Chattopadhyay, Jogen Debnath (Department of Human Physiology with Community Health, Vidyasagar University, Midnapore\|721 102, West Bengal, India) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第3期286-289,共4页
Changes in the activities of Δ 5\|3β\|hydroysteroid dehydrogenase(HSD) in testis and adrenal gland, 17β\|hydroxysteroid dehydrogenase in testis, acid and alkaline phosphatase in testis, prostate and seminal vesic... Changes in the activities of Δ 5\|3β\|hydroysteroid dehydrogenase(HSD) in testis and adrenal gland, 17β\|hydroxysteroid dehydrogenase in testis, acid and alkaline phosphatase in testis, prostate and seminal vesicle were observed in noise exposed mature rats at the intensity of 85 dB for 8 h/day for 45 days. The results indicated that noise exposed group showed a significant diminution in the activities of androgenic key enzymes Δ 5\|3β and 17β\|HSD, acid phosphatase in testis, prostate and seminal vesicle. There was a significant elevation in the activities of adrenal Δ 5\|3β\|HSD, alkaline phosphatase in testis and other accessory sex organ in noise exposed group. Gonadosomatic, prostatosomatic and seminal vesiculo\|somatic indexes were decreased significantly in noise exposed group. Therefore, it is evident that noise exposure at 85dB exerts a deleterious effect on testicular and adrenocortical activities. 展开更多
关键词 noise hydroxysteroid dehydrogenase acid phosphatase alkaline phosphatase sex organs adrenal cortex
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Effects of alkaline ameliorator additions on the acidic buffering abilities of aluminum-rich alfisols
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作者 Wu Jiemin Shao Feng(Department of Environmental Science, Zhejiang Agricultural University, Hangzhou 310029 , China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第2期235-241,共7页
Lime and coal flying ash applications could mitigate pollution from acid deposition and improve the buffering ability of two acidic soils sampled from Zhejiang Province. The results showed that soil alkalinity and aci... Lime and coal flying ash applications could mitigate pollution from acid deposition and improve the buffering ability of two acidic soils sampled from Zhejiang Province. The results showed that soil alkalinity and acidified buffering capacities (QpHs ) were significantly increased, especially for liming treatment; whereas, the amounts of SO24- adsorbed by treated soils were decreased to some degrees because net negative charges of soil oxide colloidal surfaces were increased with the decrease in soil acidity, although the soil fixation abilities for adsorbed SO24- were not reduced. These facts indicated that after the alkaline ameliorators were applied, the positive and adverse effects resulted from sulfate-type acid deposition were simultaneously existed in these soil treatments. 展开更多
关键词 acidic alfisol alkaline ameliorator acidified buffering capacity.
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Effects of heat shock on change of HSC70/HSP68,acid and alkaline phosphatases before and after rat partial hepatectomy 被引量:27
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作者 Lu AL Xu CS 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第5期730-733,共4页
INTRODUCTIONOnly the liver has the great capability ofregeneration in mammal.Few hepatocytes are inthe phase of division in the normal liver of an adultmammal (including human beings),but theremaining hepatocytes can ... INTRODUCTIONOnly the liver has the great capability ofregeneration in mammal.Few hepatocytes are inthe phase of division in the normal liver of an adultmammal (including human beings),but theremaining hepatocytes can be induced to proliferatequickly by partial hepatectomy (PH),and,to somedegree,they stop dividing and re-differentiate intocells functioning as hepatocytes.This shows 展开更多
关键词 partial hepatectomy(PH) liver regeneration CONSERVED HEAT-SHOCK PROTEIN 70/induced HEAT-SHOCK PROTEIN 68(HSCT0/HSP68) acid PHOSPHATASES alkaline PHOSPHATASES
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Acid equilibrium during bioleaching of alkaline low-grade sulfide copper ore 被引量:4
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作者 WEN Jiankang RUAN Renman YAO Guocheng SONG Yongsheng 《Rare Metals》 SCIE EI CAS CSCD 2006年第6期680-686,共7页
This article reports the study on acid equilibrium during bioleaching of alkaline low-grade copper sulfide ore. Adding auxiliary agents 1# (sulfur) and 2# (pyrite) makes bacterial leaching of copper and acid produ... This article reports the study on acid equilibrium during bioleaching of alkaline low-grade copper sulfide ore. Adding auxiliary agents 1# (sulfur) and 2# (pyrite) makes bacterial leaching of copper and acid production carried out simultaneously because the auxiliary agents can be oxidized by bacteria and the oxidation products involve acid. The acid required for dissolving alkaline gangue during bacterial leaching is produced, and acid equilibrium is reached during the ore bio-leaching. The recovery of copper reaches more than 95%. 展开更多
关键词 BIOLEACHING alkaline low-grade copper sulfide ore acid equilibrium process mineralogy auxiliary agent
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Oxidation of propane to acrylic acid and acetic acid over alkaline earth-doped Mo-V-Sb-O_x catalysts 被引量:2
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作者 Chandan S.Chaudhari Shailesh S.Sable +2 位作者 Hanumant Gurav Ashutosh A.Kelkar Vilas H.Rane 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第6期593-599,共7页
Alkaline earth metal (Mg,Ca,Sr and Ba)-doped Mo-V-Sb-O x catalysts,prepared by a dry-up method,have been investigated for their catalytic performance in the oxidation of propane under different reaction conditions.T... Alkaline earth metal (Mg,Ca,Sr and Ba)-doped Mo-V-Sb-O x catalysts,prepared by a dry-up method,have been investigated for their catalytic performance in the oxidation of propane under different reaction conditions.The catalysts have been characterized by N2 adsorption-desorption,temperature-programmed desorption (TPD) of NH3,SEM and XRD.Influence of water vapor on the catalytic performance,particularly on the selectivities to acetic acid and acrylic acid,has also been studied.The selectivity to acrylic acid was improved significantly by the doping of alkaline earth metals to Mo-V-Sb-O x catalysts.The surface acidic sites of the catalyst decreased with the doping of the catalyst with alkaline earth metals,which ultimately was found to be beneficial for obtaining high selectivity to acrylic acid.The catalytic activity and product selectivities were found to be influenced by the reaction temperature,C3H8/O2 ratio and space velocity.A significant improvement in the selectivity to acrylic acid has also been observed by the addition of water vapor in the feed of propane and oxygen in the oxidation of propane. 展开更多
关键词 oxidation of propane surface acidity alkaline earth doped Mo-V-Sb-Ox catalysts acrylic acid acetic acid
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RNAi-mediated suppression of the abscisic acid catabolism gene Os ABA8ox1 increases abscisic acid content and tolerance to saline–alkaline stress in rice(Oryza sativa L.) 被引量:7
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作者 Xiaolong Liu Xianzhi Xie +6 位作者 Chongke Zheng Lixing Wei Xiaowei Li Yangyang Jin Guohui Zhang Chang-Jie Jiang Zhengwei Liang 《The Crop Journal》 SCIE CSCD 2022年第2期354-367,共14页
Saline–alkaline(SA) stress is characterized by high salinity and high alkalinity(high p H), which severely inhibit plant growth and cause huge losses in crop yields worldwide. Here we show that a moderate elevation o... Saline–alkaline(SA) stress is characterized by high salinity and high alkalinity(high p H), which severely inhibit plant growth and cause huge losses in crop yields worldwide. Here we show that a moderate elevation of endogenous abscisic acid(ABA) levels by RNAi-mediated suppression of Os ABA8 ox1(Os ABA8 ox1-kd), a key ABA catabolic gene, significantly increased tolerance to SA stress in rice plants. We produced Os ABA8 ox1-kd lines in two different japonica cultivars, Dongdao 4 and Nipponbare. Compared with nontransgenic control plants(WT), the Os ABA8 ox1-kd seedlings accumulated 25.9%–55.7% higher levels of endogenous ABA and exhibited reduced plasmalemma injury, ROS accumulation and Na;/K;ratio, and higher survival rates, under hydroponic alkaline conditions simulated by 10, 15, and 20 mmol L-1 of Na;CO;. In pot trials using SA field soils of different alkali levels(p H 7.59, 8.86, and 9.29), Os ABA8 ox1–kd plants showed markedly higher seedling survival rates and more vigorous plant growth, resulting in significantly higher yield components including panicle number(85.7%–128.6%), spikelets per panicle(36.9%–61.9%), branches(153.9%–236.7%), 1000–kernel weight(20.0%–28.6%), and percentage of filled spikelets(96.6%–1340.8%) at harvest time. Under severe SA soil conditions(p H = 9.29, EC = 834.4 μS cm-1),Os ABA8 ox1-kd lines showed an 194.5%–1090.8% increase in grain yield per plant relative to WT plants.These results suggest that suppression of Os ABA8 ox1 to increase endogenous ABA levels provides a new molecular approach for improving rice yield in SA paddies. 展开更多
关键词 Rice(Oryza sativa L.) Saline–alkaline stress Abscisic acid(ABA) OsABA8ox1-kd Endogenous ABA levels
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Methanol oxidation in acidic and alkaline electrolytes using PtRuIn/C electrocatalysts prepared by borohydride reduction process 被引量:1
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作者 Santos M.C.L. Nandenha J. +2 位作者 Ayoub J.M.S. Assumpao M.H.M.T. Neto A.O. 《燃料化学学报》 EI CAS CSCD 北大核心 2018年第12期1462-1471,共10页
PtRuIn/C electrocatalysts( 20% metal loading by weight) were prepared by sodium borohydride reduction process using H_2PtCl6·6H_2O,RuCl_3·xH_2O and InCl_3·xH_2O as metal sources,borohydride as reducing ... PtRuIn/C electrocatalysts( 20% metal loading by weight) were prepared by sodium borohydride reduction process using H_2PtCl6·6H_2O,RuCl_3·xH_2O and InCl_3·xH_2O as metal sources,borohydride as reducing agent and Carbon Vulcan XC72 as support. The synthetized PtRuIn/C electrocatalysts were characterized by X-ray diffraction( XRD),energy dispersive analysis( EDX),transmission electron microscopy( TEM),cyclic voltammetry( CV),chronoamperommetry( CA) and polarization curves in alkaline and acidic electrolytes( single cell experiments). The XRD patterns showPtpeaks are attributed to the face-centered cubic( fcc) structure,and a shift of Pt( fcc) peaks indicates that Ru or In is incorporated into Ptlattice. TEMmicrographs showmetal nanoparticles with an average nanoparticle size between 2.7 and 3.5 nm. Methanol oxidation in acidic and alkaline electrolytes was investigated at room temperature,by CV and CA. PtRu/C( 50 ∶ 50) shows the highest activity among all electrocatalysts in study considering methanol oxidation for acidic and alkaline electrolyte. Polarization curves at 80 ℃ showPtRuIn/C( 50 ∶ 25 ∶ 25)with superior performance for methanol oxidation,when compared to Pt/C,PtIn/C and PtRu/C for both electrolytes. The best performance obtained by PtRuIn/C( 50 ∶ 25 ∶ 25) in real conditions could be associated with the increased kinetics reaction and/or with the occurrence simultaneously of the bifunctional mechanism and electronic effect resulting from the presence of Ptalloy. 展开更多
关键词 BOROHYDRIDE reduction process PtRuIn/C ELECTROCATALYSTS METHANOL oxidation acidIC and alkalinE electrolytes polarization CURVES
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Effects of applied potential on the stress corrosion cracking behavior of 7003 aluminum alloy in acid and alkaline chloride solutions 被引量:5
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作者 Xiao-yan Zhang Ren-guo Song +2 位作者 Bin Sun Hai Lu Chao Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第7期819-826,共8页
Potentiodynamic polarization tests and slow strain rate test(SSRT) in combination with fracture morphology observations were conducted to investigate the stress corrosion cracking(SCC) behavior of 7003 aluminum al... Potentiodynamic polarization tests and slow strain rate test(SSRT) in combination with fracture morphology observations were conducted to investigate the stress corrosion cracking(SCC) behavior of 7003 aluminum alloy(AA7003) in acid and alkaline chloride solutions under various applied potentials(Ea). The results show that AA7003 is to a certain extent susceptible to SCC via anodic dissolution(AD) at open-circuit potential(OCP) and is highly susceptible to hydrogen embrittlement(HE) at high negative Ea in the solutions with p H levels of 4 and 11. The susceptibility increases with negative shift in the potential when Ea is less than-1000 m V vs. SCE. However, the susceptibility distinctly decreases because of the inhibition of AD when Ea is equal to-1000 m V vs. SCE. In addition, the SCC susceptibility of AA7003 in the acid chloride solution is higher than that in the alkaline solution at each potential. Moreover, the effect of hydrogen on SCC increases with increasing hydrogen ion concentration. 展开更多
关键词 aluminum alloys stress corrosion cracking susceptibility hydrogen embrittlement potential acid solutions alkaline solutions
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Corrosion-wear behavior of nanocrystalline Fe88Si12 alloy in acid and alkaline solutions
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作者 Li-cai Fu Wen Qin +2 位作者 Jun Yang Wei-min Liu Ling-ping Zhou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第1期75-82,共8页
The corrosion-wear behavior of a nanocrystalline Fe_(88)Si_(12) alloy disc coupled with a Si_3N_4 ball was investigated in acid(pH 3) and alkaline(pH 9) aqueous solutions. The dry wear was also measured for re... The corrosion-wear behavior of a nanocrystalline Fe_(88)Si_(12) alloy disc coupled with a Si_3N_4 ball was investigated in acid(pH 3) and alkaline(pH 9) aqueous solutions. The dry wear was also measured for reference. The average friction coefficient of Fe_(88)Si_(12) alloy in the pH 9 solution was approximately 0.2, which was lower than those observed for Fe_(88)Si_(12) alloy in the pH 3 solution and in the case of dry wear. The fluctuation of the friction coefficient of samples subjected to the pH 9 solution also showed similar characteristics. The wear rate in the pH 9 solution slightly increased with increasing applied load. The wear rate was approximately one order of magnitude less than that in the pH 3 solution and was far lower than that in the case of dry wear, especially at high applied load. The wear traces of Fe_(88)Si_(12) alloy under different wear conditions were examined and analyzed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The results indicated that the tribo-chemical reactions that involve oxidation of the worn surface and hydrolysis of the Si_3N_4 ball in the acid solution were restricted in the pH 9 aqueous solution. Thus, water lubrication can effectively improve the wear resistance of nanocrystalline Fe_(88)Si_(12) alloy in the pH 9 aqueous solution. 展开更多
关键词 iron silicon alloys nanocrystalline alloys wear behavior CORROSION acid solutions alkaline solutions
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Effects of Headgroups and Serum on Gene Transfection of Alkaline Amino Acid Based Cationic Lipids
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作者 LI Li YANG Yang NIE Yu HE Bin GU Zhong-wei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第1期69-71,共3页
Three cationic lipids with lysylated(1), histidylated(2), and arginylated(3) headgroups and cholesterol hydrophobic moiety were synthesized. The average sizes of liposomes and lipoplexes were around 100 and 160 ... Three cationic lipids with lysylated(1), histidylated(2), and arginylated(3) headgroups and cholesterol hydrophobic moiety were synthesized. The average sizes of liposomes and lipoplexes were around 100 and 160 nm, respectively. The gene transfection efficiency of the three lipoplexes loaded with pGL3 or pORF-LacZ was compared on 293T cells in the presence or the absence of serum. The transfection efficiency of the three lipoplexes in a serum-free medium was 2 to 3-fold higher than that of dioleoyl-trimethylammonium propane(DOTAP). In the presence of serum, however, most of the lipoplexes showed lower transfection activities; only lipoplex 3 retained its high transfection efficiency. 展开更多
关键词 Cationic lipids alkaline amino acids SERUM Gene delivery Transfection efficiency
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Effects of temperature and concentration of sulfuric acid on the electrodeposition of grainy electrolytic manganese dioxide
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作者 Huajun Guo Xinhai Li Luping Liu Xinming Zhang Zhixing Wang Wenjie Peng Bingquan Zhu 《Journal of University of Science and Technology Beijing》 CSCD 2005年第6期553-557,共5页
The effects of temperature and the concentration of sulfuric acid on the cell voltage, the anode current efficiency of electrodeposition and the particle size of grainy electrolytic manganese dioxide (EMD) were inve... The effects of temperature and the concentration of sulfuric acid on the cell voltage, the anode current efficiency of electrodeposition and the particle size of grainy electrolytic manganese dioxide (EMD) were investigated. The structure, particle size and appearance of grainy EMD were determined by powder X-ray diffraction, laser particle size analysis and scanning electron micrograph measurements. As the concentration of sulfuric acid increases, both the cell voltage and the average anode current efficiency decrease. With the increase of electrolysis temperature in the range of 30-60℃, the cell voltage, average anode current efficiency and particle size decrease. The optimum temperature of 30℃ and concentration of sulfuric acid of 2.5 mol/L for electrodeposition of the grainy EMD were obtained. XRD patterns show that the grainy EMD electrodeposited under the optimum conditions consists of γ-MnO2 and has an orthorhombic lattice structure. According to the results of SEM, the grainy EMD has a spherical or sphere-like appearance and a narrow particle size distribution with an average size of about 7μm. The grainy EMD is a promising cathode of rechargeable alkaline batteries for high energy density and a prospective precursor for production of the LiMn2O4 cathode of lithium ion batteries. 展开更多
关键词 alkaline batteries electrolytic manganese dioxide TEMPERATURE sulfuric acid ELECTRODEPOSITION
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POLAROGRAPHIC CHARACTERISTICS OF TELLURIUM(Ⅳ)IN ALKALINE DYE-ACID SOLUTION
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作者 Li Hua ZHU He Qing TANG Wen Zhao SHI Department of Chemistry,Huazhong University of Science and Technology,Wuhan,430074 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期239-240,共2页
Polarographic characteristics of Te(Ⅳ)-alkaline dye were investiga- ted at mercury electrode in acidic solution.It was found that the mechanism of the electrode process depended on the concentration of Te(Ⅳ).
关键词 IV IN alkalinE DYE-acid SOLUTION POLAROGRAPHIC CHARACTERISTICS OF TELLURIUM acid TE
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Improving the Dietary Protein Quality by Amino Acid Fortification with a High Inclusion Level of Micro Algae (<i>Spirulina platensis</i>) or Insect Meal (<i>Hermetia illucens</i>) in Meat Type Chicken Diets 被引量:4
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作者 Carmen Neumann Susanne Velten Frank Liebert 《Open Journal of Animal Sciences》 2018年第1期12-26,共15页
The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM... The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM). N balance experiments were based on the quantitative excreta collection method, divided into starter period (10 - 20 d) and grower period (25 - 35 d). The study utilized 70 all male meat type chicken (Ross 308). Data assessment applied the exponential N utilization model of the “Goettingen approach”. The control diet was based on wheat, corn and SBM. In four experimental diets SBM was completely substituted by SM or HM, but fortified with feed amino acids (AA) both on a basic level of supplementation (Lys and Met added equal to the control diet) and on an extended level (Lys, Met, Thr, Arg, Val, Ile, His added). At a basic level of AA supplementation, complete replacement of SBM by SM or HM in chicken diets depressed dietary protein quality significantly (p 0.05). However, the extended level of AA supplementation improved protein quality parameters of the diets with both of the alternative proteins significantly (p < 0.05), but still generally not on par with the control diet. The observed responses were accentuated when the well-known effect of N intake on protein utilization was eliminated through the standardization of N intake by application of the “Goettingen approach”. 展开更多
关键词 N Balance Growing Chickens N Utilization Model Amino acids Protein Qual-ity SPIRULINA PLATENSIS Hermetia illucens
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Effect of Ascorbic Acid Supplementation on Liver Function Tests in Hepatitis C Patients
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作者 Iffat Nayila 《Open Journal of Internal Medicine》 2020年第3期263-279,共17页
An isolated liver function test is of little role in selection of liver disease because many harmful liver diseases may be correlated with normal levels of LFT’s. The outline of enzyme abnormalities in the perspectiv... An isolated liver function test is of little role in selection of liver disease because many harmful liver diseases may be correlated with normal levels of LFT’s. The outline of enzyme abnormalities in the perspective of patient’s commonly observed symptoms and laboratory data might be helpful in directing the subsequent diagnosis of liver diseases. Liver Function Tests (LFTs) are most generally used screening blood tests for assessment of different liver diseases and these tests provide a lot of evidence for disease processes whether for the purpose of investigation of supposed liver disease or help in observing the progress of disease action or simply by blood investigation. The evaluation of different liver enzymes simply gives diagnostic information on basic level whether patient’s principal disorder is actually hepatitis or cholestasis in source. However, it is necessary in various cases to evaluate LFTs with knowledge of liver functioning enzyme fractions. The objective of this study was to explore the effects of ascorbic acid supplementation on serum liver function tests in Hepatitis C patients. A total of 100 hepatitis C patients were selected randomly. 50 were given ascorbic acid supplementation for one month along with anti HCV treatment. The other 50 HCV patients took their normal anti HCV treatment without intake of ascorbic acid supplementation, and serum ascorbic acid level and liver function test parameters were observed before and after intake of ascorbic acid in both groups. The liver function parameters determined were aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), serum total bilirubin, direct bilirubin, indirect bilirubin and serum protein (total protein, albumin, globulin and A/G ratio). These parameters along with serum ascorbic acid were measured before and 30 days after vitamin C supplementation. Various abnormally elevated LFTs were also improved more rapidly when compared to other group which was not given ascorbic acid supplements for the period of one month. There was a significant change in levels of some liver function parameters before and after intake of ascorbic acid supplementation, and various abnormally elevated LFTs were also improved when compared to other group which was not given ascorbic acid supplements for the period of one month. The effect of Vitamin C supplementation was more marked on serum aminotransferase levels. After one-month use of ascorbic acid, serum alanine aminotransferase (p < 0.042) and serum aspartate aminotransferase (p < 0.000) levels were significantly decreased in hepatitis C patient group. In HCV group with ascorbic acid supplementation, serum total bilirubin (p < 0.046) and serum direct bilirubin (p < 0.048) were found to be less than the pre values when compared to HCV group without ascorbic acid supplementation. It was also observed that some of protein values were suggestively improved after intake of ascorbic acid supplementation. 展开更多
关键词 Supplementation Ascorbic acid Liver Function Tests Alanine Aminotransferase Aspartate Aminotransferase SIGNIFICANT DIAGNOSES alkaline Phosphatase
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