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Organic Acids Secreted from Plant Roots under Soil Stress and Their Effects on Ecological Adaptability of Plants 被引量:12
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作者 黄文斌 马瑞 +2 位作者 杨迪 刘星平 宋金凤 《Agricultural Science & Technology》 CAS 2014年第7期1167-1173,共7页
[Objective] In this study,the secretion of organic acids from plant roots under soil nutrient and water stress and the effects of organic acids on ecological adaptability of plants were investigated,which provided the... [Objective] In this study,the secretion of organic acids from plant roots under soil nutrient and water stress and the effects of organic acids on ecological adaptability of plants were investigated,which provided theoretical basis for improving the adaptability of plants to a variety of stress conditions.The results showed that,under nutrient and water stress,the content of organic acids secreted from plant roots increased significantly as a common active adaptive response.Organic acids could improve the activities of a variety of antioxidant enzymes,contents of osmotic regulatory substances,contents of chlorophyll and photosynthesis levels,promote nutrient absorption and transportation in plants,and ultimately contribute to plant growth and biomass accumulation,reduce the toxicity of stress conditions to plants and improve the stress resistance and adaptability of plants. 展开更多
关键词 Nutrient stress Water stress Organic acids secreted from plant roots plant ecological adaptability
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Real-Time PCR Technique and Its Application in Quantification of Plant Nucleic Acid Molecules 被引量:8
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作者 刘进元 《Acta Botanica Sinica》 CSCD 2003年第6期631-637,共7页
Real-time PCR is a closed DNA amplification system that skillfully integrates biochemical, photoelectric and computer techniques. Fluorescence data acquired once per cycle provides rapid absolute quantification of ini... Real-time PCR is a closed DNA amplification system that skillfully integrates biochemical, photoelectric and computer techniques. Fluorescence data acquired once per cycle provides rapid absolute quantification of initial template copy numbers as PCR products are generated. This technique significantly simplifies and accelerates the process of producing reproducible quantification of nucleic acid molecules. It not only is a sensitive, accurate and rapid quantitative method, but it also provides an easier way to calculate the absolute starting copy number of nucleic acid molecules to be tested. Together with molecular bio-techniques, like microarray, real-time PCR will play a very important role in many aspects of molecular life science such as functional gene analysis and disease molecular diagnostics. This review introduces the detailed principles and application of the real-time PCR technique, describes a recently developed system for exact quantification of AUX/IAA genes In Arabidopsis, and discusses the problems with the real-time PCR process. 展开更多
关键词 real-time PCR technique quantification of plant nucleic acid molecules gene expression molecular medicine
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Key Organic Acids in Indigenous Plants in Thailand 被引量:1
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作者 Benyathip Sukontaprapun Somsri Charoenkiatkul +3 位作者 Parunya Thiyajai Monruedee Sukprasansap Preecha Saetang Kunchit Judprasong 《American Journal of Plant Sciences》 2019年第10期1855-1870,共16页
Organic acids had various health benefits such as citric acid can inhibit stone formation and break up beginning of small kidney stone. On the other hand, some organic acid showed negative health effects such as oxali... Organic acids had various health benefits such as citric acid can inhibit stone formation and break up beginning of small kidney stone. On the other hand, some organic acid showed negative health effects such as oxalic acid acts as anti-nutrients and can cause kidney stone. Most of Thai indigenous plants had sour taste;however general people believed that sour taste of plants could contain high ascorbic acid. In addition, there is limit report of organic acids and ascorbic acid in Thai indigenous plants. This study determined organic acids, ascorbic acid, pH, and total acidity in indigenous plants. Forty samples of 29 types of indigenous plants were analyzed. Results showed that young leaves of Cratoxylum formosum found the highest succinic acid (2454 ± 91 mg/100g fresh weight, FW) and high ascorbic acid (142 ± 35 mg/100g FW). Fruits of Antidesma ghaesembilla had high citric acid levels (5161 ± 109 mg/100g FW) but contained very low ascorbic acid (2 mg/100g FW). The sum of organic acids had significant and inverse correlations with pH (r = -0.680) and positive with total acidity (r = 0.672) but was not significantly correlated for ascorbic acid (r = 0.536). The sour taste of plants could derive from the sum of organic, citric, and formic acids, but not other organic and ascorbic acids. Against traditional belief, plants having a strong sour taste may not contain significantly high amounts of ascorbic acid. 展开更多
关键词 Indigenous plantS ORGANIC acidS Ascorbic acid TOTAL acidITY
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Rapid and sensitive method for determining free amino acids in plant tissue by high-performance liquid chromatography with fluorescence detection 被引量:1
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作者 Nengjian Zheng Huayun Xiao +2 位作者 Zhongyi Zhang Xiaofei Gao Jingjing Zhao 《Acta Geochimica》 EI CAS CSCD 2017年第4期680-696,共17页
This paper describes a reliable and rapid method for the complete separation and quantitation of twenty-five amino acids typically found in plants, based on reversed phase high-performance liquid chromatography–linke... This paper describes a reliable and rapid method for the complete separation and quantitation of twenty-five amino acids typically found in plants, based on reversed phase high-performance liquid chromatography–linked fluorescence detector using a 150×4.6 mm Zorbax Eclipse AAA column. Plant tissue free amino acids(FAA)were extracted by ultrasonication with 5%(v/v) aqueous trifluoroacetic acid followed by ultrafiltration of extracts.The following analysis of amino acids was performed through programmed precolumn derivatization with orthophthalaldehyde and 9-fluorenylmethyl chloroformate reagents and efficient elution of derivatives within 26 min using binary gradient scheme. The method was validated over a concentration range of 4.5–450 μmol L^(-1)(μM).Separation analysis showed good selectivity(resolution>1.5) for most amino acids. The average repeatability(RSD%, relative standard deviation) of the analysis at seven calibration concentrations was below 4% and ranged from 1.13% to 12.04%. The intra-day mean coefficient of variation at two concentrations(22.5 and 90 μM) was within 2%, and the intermediate precision was less than 4%. The limits of detection were between 0.012 and 6.68 μM. The coefficients of determination(R2) of the linear calibration curves were from 0.9989 to 0.9999.When the method was applied to plant samples, the FAA recoveries at two spiked levels(25 and 100 μM) ranged from 67.0% to 108.9% with an average of 94.4%, and the precision was 0.26%–12.31% RSD. A specific application combining this method with optimized extraction and interference removal procedures was successfully used to determine the FAA pools in different plant tissues. Finally,a PLS-DA multivariate statistics model was validated for the classification of three plant species according to their FAA profiles. 展开更多
关键词 HPLC OPA FMOC Free amino acids plant PLS-DA
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Effects of Plant-derived Humic Acid Organic Fertilizer on Selenium Content of Rice in Northern Guangxi 被引量:1
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作者 Yunwei JIANG Lixiu HUANG +10 位作者 Dongmei WANG Liping PAN Qianchi MO Ri MING Zongji ZHANG Jinping CHEN Hengzhi ZHAO Youxing YANG Xiongying JIANG Dayong FAN Yongxian LIU 《Agricultural Biotechnology》 CAS 2019年第3期156-158,共3页
This study was to find out the suitable application amount of plant-derived humic acid organic fertilizer for selenium-rich rice production in northern Guilin area by applying the fertilizer at different amounts.The r... This study was to find out the suitable application amount of plant-derived humic acid organic fertilizer for selenium-rich rice production in northern Guilin area by applying the fertilizer at different amounts.The results showed that plant-derived humic acid organic fertilizer could effectively activate selenium in selenium-rich soil,and then promote the uptake of selenium by rice.With costs,selenium enrichment and rice yield as the main evaluation indicators,A4 was chosen as the best treatment,that is,the application of 4 500 kg/hm^2 of plant-derived humic acid organic fertilizer as base fertilizer could achieve the best benefit. 展开更多
关键词 plant-derived HUMIC acid organic fertilizer RICE Selenium-rich
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Relative sensitivities of woody plants to acid deposition in south areas of China 被引量:1
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作者 Feng Zongwei and Shan YunfengResearch Center for Eco-Environmental Sciences,Academia Sinica,Beijing 100083,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1991年第2期61-68,共8页
Relative sensitivities of 30 species of common woody plants to simulated acid rain with pH values of 2.0, 2.5, 3.0, 3.5, 4.5 and control were studied. The results showed that 6 species of these plants were sensitive t... Relative sensitivities of 30 species of common woody plants to simulated acid rain with pH values of 2.0, 2.5, 3.0, 3.5, 4.5 and control were studied. The results showed that 6 species of these plants were sensitive to simulated acid rain. The moderate included 18 species. The resistant included 6. Relative sensitivities to ambient acid rain and air pollutants and visible injury degree of 30 species of common woody plants in Chongqing City were investigated. Results showed that 6 species with foliage lesion rate at above 10 percent were sensitive, that 6 species with no lesion were resistant and that other 18 species with lesion at 10 percent below were moderate. Other 7 cities (Guiyang, Zunyi, Duyun, Changsha, Zhuzhou, Liuzhou and Guilin City) were also investigated and results were consistent with those of Chongqing City. The experimental and investigated results showed relative sensitivities and visible injury degree of woody plants to simulated acid rain were consistent with those of the woody plants to ambient acid rain and air pollutants. The sensitive plants may be used as bioindicators to acid rain or air pollutants. The resistant species can be introduced to acid rain and air pollution areas to substitute damaged sensitive plants in order to improve environment. 展开更多
关键词 relative sensitivity acid rain woody plant.
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Antimicrobial activity of kojic acid from endophytic fungus Colletotrichum gloeosporioides isolated from Sonneratia apetala,a mangrove plant of the Sundarbans 被引量:1
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作者 Tauhidur Rahman Nurunnabi Shaymaa Al-Majmaie +7 位作者 Ismini Nakouti Lutfun Nahar S.M.Mahbubur Rahman Md.Hossain Sohrab Md.Morsaline Billah Fyaz M.D.Ismail George P.Sharples Satyajit D.Sarker 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2018年第5期350-354,共5页
Objective: To isolate and evaluate the antimicrobial activity of the active principle(s) from the ethyl acetate(EtOAc) extract of endophytic fungus Colietotrichum gloeosporioides(C.gloeosporioides) isolated from Sonne... Objective: To isolate and evaluate the antimicrobial activity of the active principle(s) from the ethyl acetate(EtOAc) extract of endophytic fungus Colietotrichum gloeosporioides(C.gloeosporioides) isolated from Sonneratia apetala. Methods: Water agar technique was used to isolate the fungus, and both microscopic and molecular techniques were used for identification of the strain. Potato dextrose broth was used to grow the fungus in large-scale. Reversed-phase preparative HPLC analysis was performed to isolate the major active compound, kojic acid. The EtOAc extract and kojic acid were screened for their antimicrobial activity against two Grampositive and two Gram-negative bacteria as well as a fungal strain using the resazurin 96-well microtitre plate antimicrobial assay. Results: The fungus C. gloeosporioides was isolated from the leaves of Sonneratia apetala. Initial identification of the fugal isolate was carried out using spore characteristics observed under the microscope. Subsequently, the ITS1-5.8 S-ITS2 sequencing was employed for species-level identification of the fungus C. gloeosporioides. Five litres of liquid culture of the fungus produced approximately 610 mg of a mixture of secondary metabolites.Kojic acid(1) was isolated as the main secondary metabolite present in the fungal extract, and the structure was confirmed by 1 D, 2 D NMR and mass spectrometry. The EtOAc extract and compound 1 exhibited considerable antimicrobial activity against all tested microorganisms.Whilst the minimum inhibitory concentration(MIC) values from the EtOAc extract ranged between 2.4×10^(-4)mg/mL and 2.5 mg/mL, those of kojic acid(1) were between 0.125 mg/mL and1 mg/mL. The EtOAc extract and kojic acid(1) were most active against Pseudomonas aeruginosa(MIC = 2.4×10^(-4). mg/mL) and Micrococcus luteus(MIC = 0.125 mg/mL), respectively. Conclusions:The results revealed that the endophytic fungus C. gloeosporioides could be a good source of commercially important kojic acid, which exhibited antimicrobial properties. 展开更多
关键词 Endophytic fungus Mangrove plants Sonneratia apetala Kojic acid Colletrtrichum gloeosporioides Antimicrobial activity
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Effect of Different Acids on the Scale in Pipelines of Linz-Donawitz (LD) Plant (Steel Making Process)
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作者 Swastic   Suprotim Das 《Advances in Chemical Engineering and Science》 2015年第2期192-196,共5页
In this report we present the effect of different acids on the scales taken from LD plant. The main aspect of the problem is to find a suitable concentration and type of acid to reduce/remove the deposition of scale i... In this report we present the effect of different acids on the scales taken from LD plant. The main aspect of the problem is to find a suitable concentration and type of acid to reduce/remove the deposition of scale in the pipeline. The analysis is carried out using a combination of suggestions dictated by experimental evidence and suitable mathematical techniques. Result reveals that 5% solution of Hydrochloric Acid is most effective to dissolve the scale in a specified time at room temperature. The order of effectiveness to dissolve the scale deposits is HCL > HNO3 > H3NSO3> H2C2O4 > H2SO4. But when it comes to the corrosion in the pipe the order of corrosion caused by acids is HCL > H3NSO3 > HNO3. So, when we consider both the results HNO3 is the most suitable acid with respect to both scale deposition and corrosion of the pipelines. Predictions of the data are compared with experiments finding a remarkable agreement with the available data. 展开更多
关键词 Scales LD plant acidS
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Response of 14C-Salicylic Acid to Heat Stress After Being Fed to Leaves of Grape Plants
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作者 LIUYue-ping HUANGWei-dong WANGLi-jun 《Agricultural Sciences in China》 CAS CSCD 2005年第2期106-112,共7页
An experiment was conducted to investigate the response of salicylic acid as a second messenger to the heat stress in grape plants. For this purpose, all leaves of grape (Vitis vinifera×V. labrussa L. cv. Jingxiu... An experiment was conducted to investigate the response of salicylic acid as a second messenger to the heat stress in grape plants. For this purpose, all leaves of grape (Vitis vinifera×V. labrussa L. cv. Jingxiu) plants were removed except the 3rd, 4th, 5th, 6th, and 7th ones. The 5th leaf was fed with C-SA, and the 4th and 6th leaves were exposed to high 14 temperature at 40±0.5°C. It was observed that more C-SA transported out from the 5th leaf and the distribution of C-SA 14 14 in each organ of plant altered in response to heat stress. The accumulation of C-SA in both the 4th and 6th leaves being 14 exposed to high temperature was at least three times higher than that in control. The distribution of C-SA in other distal 14 leaves (the 3rd and 7th leaf) decreased, but more C-SA accumulated in stems adjacent to the 4th or 6th leaf exposed to 14 high temperature. In addition, there was more C-SA being transported upwards or downwards while the 4th and 6th 14 leaves were exposed to high temperature respectively. Therefore, our results suggested that SA was closely involved in signal transduction of heat stress in grape plants. However, the ratio of C radioactivity assayed after SA being extracted 14 to that of direct assay with apparatus was more than 70%, which indicated about 30% C was lost or catabolized during 14 transportation. 展开更多
关键词 Grape plant Heat stress C-salicylic acid RESPONSE Leaf 14
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刺通草的营养成分分析及其氨基酸评价 被引量:1
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作者 陈玉芹 赵成法 +4 位作者 沐远 王春梅 尹红星 匡钰 胡永亮 《食品安全质量检测学报》 CAS 2024年第7期305-313,共9页
目的研究刺通草各部位营养成分,评价其氨基酸营养价值。方法通过对刺通草花苞、嫩叶、老叶、茎皮等部位的蛋白质、总灰分、氨基酸、氮、磷、钾、钙进行测定与分析,综合评价各部位的营养情况。结果刺通草不同部位的营养成分存在差异,花... 目的研究刺通草各部位营养成分,评价其氨基酸营养价值。方法通过对刺通草花苞、嫩叶、老叶、茎皮等部位的蛋白质、总灰分、氨基酸、氮、磷、钾、钙进行测定与分析,综合评价各部位的营养情况。结果刺通草不同部位的营养成分存在差异,花苞的蛋白质及氮、磷、钾含量最高,分别为18.60%、2.98%、0.512%、3.00%;茎皮中总灰分和钙含量最高,分别为31.32%、7.28%,约为花苞和叶的3倍。各部位均检测到16种氨基酸和6种必需氨基酸,总氨基酸含量为47.59~106.57 mg/g,必需氨基酸含量为17.07~38.14 mg/g,必需氨基酸占总氨基酸含量的34.70%~40.27%。精氨酸、谷氨酸、天冬氨酸为花苞和茎皮的主要氨基酸;谷氨酸、天冬氨酸、亮氨酸为嫩叶和老叶的主要氨基酸;刺通草各部位的第一限制性氨基酸为蛋氨酸+胱氨酸;各部位呈味氨基酸和药用氨基酸含量丰富,分别占总氨基酸的88%和56%以上。各部位的氨基酸比值系数分(score of ratio coefficient of amino acid,SRC)值介于65.42~71.11之间,平均值为67.16。结论刺通草花苞的蛋白质等营养含量丰富,叶的氨基酸营养价值较高,茎皮中钙含量非常丰富。本研究可为刺通草资源开发和利用提供科学参考。 展开更多
关键词 刺通草 营养价值 氨基酸 药食两用植物
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Effect of Dominant Semi-Dwarf Gene on Plant Height and Its Related Traits and Sensitivity to Gibberellic Acid in Rice
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作者 LIU Bin-mei CHENG Can +4 位作者 Wu Yue-jin TONG Ji-ping WU Jin-hua ZHANG Ying YUAN Qin 《Rice science》 SCIE 2006年第3期179-184,共6页
Six pairs of tall and dwarf near-isogenic lines derived from a dominant semi-dwarf mutant (Y98149) were selected to study height expression and sensitivity to gibberellic acid (GA3). The lengths of the 4-5th inter... Six pairs of tall and dwarf near-isogenic lines derived from a dominant semi-dwarf mutant (Y98149) were selected to study height expression and sensitivity to gibberellic acid (GA3). The lengths of the 4-5th internode, the 3rd, 2nd, 1st internodes from the top and the panicle length in the six dwarf near isogenic lines were 97.2%, 53.3%, 65.1%, 61.9% and 94.7% of those in the six tall ones, respectively, indicating that the dominant semi-dwarfing gene significantly inhibited the internode elongation. Moreover, Y98149 (mutant type) was more sensitive to GA3 than Y98148 (wild type), and had a lower GA3 concentration in plant, about 78% of Y98148. 展开更多
关键词 semi-dwarf gene near isogenic lines plant height internode length sensitivity gibberellic acid RICE
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植物生长调节剂对‘小米’红花油茶苗木生长的影响 被引量:1
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作者 张永明 刘红位 +1 位作者 李甜江 陈璐 《西部林业科学》 CAS 北大核心 2024年第2期72-80,共9页
为探究植物生长调节剂对‘小米’红花油茶苗木生长的作用以及最佳施用量,采用赤霉素(GA3)和吲哚乙酸(IAA)二因素三水平3×3回归设计,选择不同浓度的GA3、IAA及其组合处理云南高山区‘小米’红花油茶嫁接苗,所得数据经过协方差排除... 为探究植物生长调节剂对‘小米’红花油茶苗木生长的作用以及最佳施用量,采用赤霉素(GA3)和吲哚乙酸(IAA)二因素三水平3×3回归设计,选择不同浓度的GA3、IAA及其组合处理云南高山区‘小米’红花油茶嫁接苗,所得数据经过协方差排除初始值影响后进行方差分析和多重比较。结果显示:(1)9种不同组合中,对苗高有极显著促进效果的最佳浓度组合是5 mg/L GA3和5 mg/L IAA,其处理比对照高出34.4%。(2)对地径有极显著促进效果的浓度组合是10 mg/L GA3+5 mg/L IAA,比对照高出24.6%。(3)9种组合中,所有处理对冠幅都有极显著促进效果,其中最佳浓度组合是0 mg/L GA3+5 mg/L IAA组合,比对照高出26.1%。研究结果表明:采用GA3的浓度为10 mg/L,IAA的浓度为0 mg/L或者5 mg/L的植物生长调节剂组合对‘小米’红花油茶嫁接苗进行喷施,可以明显促进其苗高、地径及冠幅的综合增长。 展开更多
关键词 ‘小米’红花油茶 植物生长调节剂 赤霉素 吲哚乙酸 苗木生长
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神经酸来源及分离方法的研究进展 被引量:1
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作者 王婕 施嘉仪 +5 位作者 高盈玺 张文静 胡雄杰 李群生 周智勇 任钟旗 《中国油脂》 CAS CSCD 北大核心 2024年第3期41-46,共6页
神经酸是一种能够疏通、修复受损神经纤维和促进神经细胞再生的单不饱和脂肪酸,可用于预防及治疗脑萎缩、阿尔茨海默病等脑疾病,具有较高的药用价值。旨在为高纯度神经酸产品的生产和发展提供参考,综述了神经酸的功效和来源,详细阐述了... 神经酸是一种能够疏通、修复受损神经纤维和促进神经细胞再生的单不饱和脂肪酸,可用于预防及治疗脑萎缩、阿尔茨海默病等脑疾病,具有较高的药用价值。旨在为高纯度神经酸产品的生产和发展提供参考,综述了神经酸的功效和来源,详细阐述了植物来源神经酸的分离方法,包括其原理和特点。不同分离方法的耦合可克服单一分离方法的某些缺点,且一定程度上解决对神经酸纯度、产量双重提高的难题,成为重要的研究方向。 展开更多
关键词 神经酸 植物 来源 分离方法
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Plant Growth Promoting Rhizobacteria Having 1-Aminocyclopropane-1-Carboxylic Acid Deaminase to Induce Salt Tolerance in Sunflower (<i>Helianthus annus L.</i>)
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作者 Muhammad Zahid Kiani Arshad Ali +2 位作者 Tariq Sultan Rizwan Ahmad Syed Ishtiaq Hydar 《Natural Resources》 2015年第6期391-397,共7页
Soil salinity badly affects agriculture productivity through accumulation of salts in upper layers of soils. The harmful effects of salts in arable lands have influenced modern as well as ancient civilizations. A pot ... Soil salinity badly affects agriculture productivity through accumulation of salts in upper layers of soils. The harmful effects of salts in arable lands have influenced modern as well as ancient civilizations. A pot study was carried out to test the performance of two PGPR isolates (KS 8, KS 28) on sunflower (SMH-0917) under different salinity levels (8, 10 and 12 dS·m-1). These salinity levels were developed by adding calculated amount of salts (NaCl, Na2SO4, CaCl2 and MgSO4) with ratio of 3:4:2:1. The bacterial strains KS 8 and KS 28 were applied separately in two treatments while third treatment was co-inoculation (KS mix). Completely randomized experimental design (CRD) was used and data were collected at flowering stage about pre-decided plant growth parameters (plant height, shoot dry weight and root dry weight). The bacterial isolate KS 8 showed an increase of 26, 102% and 83% in plant height, shoot dry weight and root dry weight at EC 8 dS·m-1, while this improvement was 67%, 163% and 296% at EC 10 dS·m-1, however an increase of 100%, 74% and 382% was recorded over control respectively at EC 12 dS·m-1. Similarly isolate KS 28 exhibited an increase of 14%, 69% and 54% in plant height;shoot dry weight and root dry weight at EC 8 dS·m-1, whereas this improvement was 56%, 163% and 188% at EC 10 dS·m-1, while an increase of 60%, 41% and 282% was registered respectively over control at EC 12 dS·m-1. The increase due to mixture treatments was 4%, 41% and 16% in plant height, shoot dry weight and root dry weight at EC 8 dS·m-1, while an increase of 33%, 57% and 100% at EC 10 dS·m-1, whereas an improvement of 53%, 33% and 164% respectively was noted at EC 12 dS·m-1 over un-inoculated. The isolate KS 8 performed better than KS 28 and mixture treatment. These two PGPR strains could be used to mitigate the adverse impact caused by salinity stress on sunflower. 展开更多
关键词 plant Growth Promoting RHIZOBACTERIA Strains 1-Aminocyclopropane-1-Carboxylic acid (ACC) DEAMINASE Salinity
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硬脂酸-CaCO_(3)协同改性对植物纤维/聚乳酸复合材料力学性能的影响 被引量:1
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作者 黄艳志 冯郁成 +4 位作者 吴树颖 高琪雅 饶婉月 董昕睿 杨飞 《中国造纸》 CAS 北大核心 2024年第4期130-139,共10页
以硬脂酸、CaCl_(2)、NaHCO_(3)和NaOH为原料,对植物纤维进行硬脂酸-CaCO_(3)协同改性,在纤维表面沉积CaCO_(3)颗粒和疏水的硬脂酸钙层,并通过造纸法制备改性植物纤维/聚乳酸(PLA)复合材料。结果表明,协同改性生成的硬脂酸钙包裹了CaCO_... 以硬脂酸、CaCl_(2)、NaHCO_(3)和NaOH为原料,对植物纤维进行硬脂酸-CaCO_(3)协同改性,在纤维表面沉积CaCO_(3)颗粒和疏水的硬脂酸钙层,并通过造纸法制备改性植物纤维/聚乳酸(PLA)复合材料。结果表明,协同改性生成的硬脂酸钙包裹了CaCO_(3)颗粒并覆盖在植物纤维表面,提高了纤维的疏水性,复合材料的力学性能随c(硬脂酸)∶c(NaHCO_(3))的增加而先增加后减小;反应温度对复合材料强度影响较小;复合材料的抗张指数和耐破指数随c(NaOH)∶c(NaHCO_(3))的增加而先增加后减小,耐折度则持续减小;最佳改性条件为:c(硬脂酸)∶c(NaHCO_(3))∶c(NaOH)=4∶6∶6、反应温度75℃,此时制备的复合材料抗张指数、耐破指数和耐折度分别为51.0 N·m/g、3.56 kPa·m^(2)/g、244次。 展开更多
关键词 植物纤维 聚乳酸 硬脂酸钙 力学性能
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不同种类添加剂对全株玉米发酵特性及营养品质的影响 被引量:2
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作者 牛琼梅 初晓辉 +5 位作者 李彦飞 桂宝林 谢勇 杨双双 马向丽 单贵莲 《饲料研究》 CAS 北大核心 2024年第1期93-98,共6页
试验旨在筛选适用于全株玉米青贮调制的添加剂种类及添加量,促进青贮玉米产业化开发。以蜡熟期全株玉米为原料,研究甲酸、乳酸菌和糖蜜对全株玉米发酵特性、营养品质及有氧稳定性的影响。结果显示:与自然发酵相比,6 mL/kg甲酸可显著降... 试验旨在筛选适用于全株玉米青贮调制的添加剂种类及添加量,促进青贮玉米产业化开发。以蜡熟期全株玉米为原料,研究甲酸、乳酸菌和糖蜜对全株玉米发酵特性、营养品质及有氧稳定性的影响。结果显示:与自然发酵相比,6 mL/kg甲酸可显著降低青贮饲料中不良微生物的数量及氨态氮(NH_(3)-N)含量(P<0.05),提高了可溶性碳水化合物(WSC)含量及有氧稳定性。添加布什乳杆菌或植物乳杆菌+布什乳杆菌复合菌剂可显著增加乙酸含量(P<0.05),降低不良微生物数量及NH_(3)-N含量,提高有氧稳定性。添加糖蜜显著增加了青贮饲料中有害菌的数量及NH_(3)-N含量(P<0.05),降低了乙酸、干物质(DM)和WSC含量。研究表明,综合考虑全株玉米青贮饲料的发酵特性、营养品质及有氧稳定性,生产中推荐采用6 mL/kg甲酸、单独添加布氏乳杆菌或按1∶5配比添加植物乳杆菌与布氏乳杆菌复合菌剂对全株玉米进行青贮。 展开更多
关键词 全株玉米 乳酸菌 糖蜜 甲酸 发酵特性 营养成分 有氧稳定性
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功能型植物纤维增强聚乳酸复合材料研究进展 被引量:1
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作者 李羽佳 王喜明 +1 位作者 姚利宏 胡建鹏 《塑料》 CAS CSCD 北大核心 2024年第3期104-108,共5页
天然植物纤维增强聚乳酸复合材料具有天然环保、可生物降解、力学性能较好等特点,已经成为极具发展潜力的“绿色材料”。功能型植物纤维增强聚乳酸复合材料的研发对于提升复合材料附加值、拓宽应用领域具有重要意义。因此,综述了植物纤... 天然植物纤维增强聚乳酸复合材料具有天然环保、可生物降解、力学性能较好等特点,已经成为极具发展潜力的“绿色材料”。功能型植物纤维增强聚乳酸复合材料的研发对于提升复合材料附加值、拓宽应用领域具有重要意义。因此,综述了植物纤维增强聚乳酸复合材料在阻燃、耐候、隔音、保温隔热、抗菌、色彩以及抗静电等领域的研究现状和进展,分析了阻燃剂、抗老化剂、保温剂、抗菌剂、颜料以及导电填物等功能型助剂选择、内在功能性机理解析、产业化技术研发以及产品功能多样性等方面存在的问题,并展望了该领域的发展趋势,以期为进一步推动功能型植物纤维增强聚乳酸复合材料的研发提供科学依据。 展开更多
关键词 植物纤维 聚乳酸 功能型复合材料 阻燃性 耐老化性
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PLA/天然废弃植物源提取物复合材料的制备与性能
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作者 宋洁 张蓉 +2 位作者 韩家旋 李胜港 余双 《化工新型材料》 CAS CSCD 北大核心 2024年第6期247-252,258,共7页
针对废弃资源综合利用和通用塑料污染问题,采用超声波辅助提取法提取天然废弃植物源有效成分,并与聚乳酸(PLA)复合,探究石榴皮提取物(PGE)和洋葱皮提取物(OPE)对PLA性能的影响。结果表明:两种提取物的加入并没有改变PLA的晶型,但提高了... 针对废弃资源综合利用和通用塑料污染问题,采用超声波辅助提取法提取天然废弃植物源有效成分,并与聚乳酸(PLA)复合,探究石榴皮提取物(PGE)和洋葱皮提取物(OPE)对PLA性能的影响。结果表明:两种提取物的加入并没有改变PLA的晶型,但提高了成核密度,减小了球晶尺寸。复合材料的热稳定性有一定的下降,但由于提取物中羟基与PLA发生了氢键作用使其下降幅度不大,同时弥补了复合材料力学性能减小的趋势。植物源提取物的添加使复合材料中的—OH基团数量增多,水蒸汽透过率也随之增大,适用于地膜及食品果蔬保鲜材料中。两种提取物赋予了复合材料不同色泽,染色成分与PLA间的界面作用使复合材料耐摩擦色牢度得以保持,扩大了其应用范围。两种复合材料具有显著的抑菌作用,其中,PGE含量为9%时,其复合材料的抗菌率可达95%以上,可以作为抗菌材料应用。 展开更多
关键词 聚乳酸 天然废弃植物源提取物 结晶性能 热稳定性 力学性能 抗菌性 耐摩擦色牢度
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玉米穗发芽突变体vp2的基因克隆及功能研究
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作者 张馨月 秦阳 +3 位作者 李瑞 黄全生 王逸茹 郑军 《作物学报》 CAS CSCD 北大核心 2024年第11期2712-2719,共8页
玉米穗发芽是指籽粒在果穗上未脱离母体时胚芽便开始萌发生长,穗发芽会严重影响玉米的产量和品质。因此高效挖掘和利用优良基因,培育抗穗发芽玉米品种对我国农业生产非常重要。本研究中的玉米穗发芽突变体vp2具有明显的穗发芽表型且性... 玉米穗发芽是指籽粒在果穗上未脱离母体时胚芽便开始萌发生长,穗发芽会严重影响玉米的产量和品质。因此高效挖掘和利用优良基因,培育抗穗发芽玉米品种对我国农业生产非常重要。本研究中的玉米穗发芽突变体vp2具有明显的穗发芽表型且性状能稳定遗传,受隐性单基因控制。通过分析vp2突变体基因组序列发现突变体中2个编码基因(Zm00001d015355和Zm00001d015356)存在缺失,Zm00001d015356编码对羟基苯丙酮酸双加氧酶(ZmHPPD1)。hppd1突变体表现穗发芽表型,且与vp2杂交后代中正常与穗发芽籽粒符合3∶1遗传分离比,结果表明Vp2编码ZmHPPD1基因。为进一步分析ZmHPPD1调控籽粒穗发芽的机制,我们检测了突变体中内源激素和ABA合成通路代谢物含量的变化,发现与正常籽粒相比,穗发芽籽粒中ABA含量显著下降,八氢番茄红素显著积累,且紫黄质、玉米黄质和叶黄素含量显著降低。这表明ZmHPPD1通过影响八氢番茄红素向番茄红素的转化,使ABA合成受阻,导致玉米籽粒打破休眠提前萌发。以上研究结果为解析玉米穗发芽的机制提供了基因资源。 展开更多
关键词 玉米 穗发芽 植物激素 脱落酸
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广西甘蔗主产区土壤酸化特征分析
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作者 曾艳 谢如林 +2 位作者 彭嘉宇 黄金生 沈小微 《南方农业学报》 CAS CSCD 北大核心 2024年第9期2623-2631,共9页
【目的】分析广西甘蔗主产区土壤pH现状和分布特点及土壤pH与交换性盐基离子含量、土壤交换性铝含量的关系,为探明广西蔗区土壤酸化机制及土壤酸化治理提供科学依据。【方法】2023年春季在广西15个甘蔗种植面积较大的县(区、市)共采集51... 【目的】分析广西甘蔗主产区土壤pH现状和分布特点及土壤pH与交换性盐基离子含量、土壤交换性铝含量的关系,为探明广西蔗区土壤酸化机制及土壤酸化治理提供科学依据。【方法】2023年春季在广西15个甘蔗种植面积较大的县(区、市)共采集515个地块的0~20 cm土壤样品,分别采用去离子水、0.01 mol/L CaCl_(2)溶液和1 mol/L KCl溶液测定土壤pH[分别标记为pH(H_(2)O)、pH(CaCl_(2))和pH(KCl)],同时测定交换性盐基离子、交换性酸和交换性铝含量,分析土壤pH与交换性盐基离子和盐基饱和度的关系,以及交换性铝积累对土壤p H的响应。【结果】广西甘蔗主产区土壤p H(H_(2)O)平均值为4.52,其中pH(H_(2)O)<4.5的强酸性土壤占63.9%;pH(CaCl_(2))和p H(KCl)平均值分别为4.06和3.71,与pH(H_(2)O)相比分别低0.46和0.81。土壤交换性酸平均含量为4.59 cmol/kg,且>6.0 cmol/kg的土壤占比32.8%。交换性铝是交换性酸的主要组分,在交换性酸含量>4.0 cmol/kg的土壤中,交换性铝占比超过80.0%。交换性铝含量与pH(KCl)的拟合优度最高(R^(2)=0.9005),当土壤交换性铝含量为2.0cmol/kg时,其所对应的pH(H_(2)O)、pH(CaCl_(2))和pH(KCl)的平均值分别为4.67、4.07和3.66。土壤交换性钙、交换性镁和交换性钾的平均含量分别为4.67、0.42和0.49cmol/kg,土壤交换性钙含量<1.5 cmol/kg的土壤占比31.1%,交换性镁含量<0.25 cmol/kg的土壤占比31.7%,交换性钾含量以介于0.2~0.6 cmol/kg的土壤占多数,约为46.8%。土壤盐基饱和度平均为49.5%,且有15.3%的土壤盐基饱和度在20%以下。盐基饱和度、交换性钙和交换性镁含量与土壤pH(H_(2)O)、pH(CaCl_(2))和pH(KCl)均呈极显著正相关(P<0.01)。【结论】广西甘蔗主产区出现严重的土壤酸化现象,pH≤4.5的土壤占大多数。钙镁缺乏、盐基饱和度偏低和铝毒危害风险较高已成为广西甘蔗主产区土壤酸化的主要特征。 展开更多
关键词 土壤酸化 土壤pH 交换性酸 交换性铝 盐基饱和度 广西蔗区
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