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Evaluation of Temporal Changes in Deep Well Water Quality in Igabi Local Government Area of Kaduna State 预览
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作者 John Jiya Musa Otuaro Ebierni Akpoebidimiyen +2 位作者 Mohammed Tanimu Musa Pius Olusegun Olufemi Dada Elijah Tsado Musa 《环境保护(英文)》 2020年第1期22-33,共12页
The research work was carried out in Igabi Local Government of Kaduna State. Thirty water samples from boreholes were randomly collected within the major towns in November to April (Dry), and May to October (Rainy sea... The research work was carried out in Igabi Local Government of Kaduna State. Thirty water samples from boreholes were randomly collected within the major towns in November to April (Dry), and May to October (Rainy season). The samples were analyzed for physical, chemical, and bacteriological parameters and to observe any changes in the groundwater quality of the area. Analysis of variance (ANOVA), Pearson Correlation were performed on the data obtained using SPSS 10.0 for a window for significant variations and inter-element relationship. High mean turbidity was recorded in boreholes in Danfili (12.2 NTU), Kwarau (6.2 NTU). Mean turbidity of 4.3 NTU was recorded in Dry season for wells with Rigachikun having 5.1 NTU. It was observed that a negative correlation exists between well depth and heavy metal concentration. There was also a linear relationship of 0.686 between well distance and nitrate (faecal contaminant). Mean value for Fluoride (0.22 mg/l), Sodium (20.78 mg/l), Calcium (15.7 mg/l), Iron (0.013 mg/l), Nitrate (3.69 mg/l), Cadmium (0.00102 mg/l) Chloride (22.107 mg/l) recorded for sampled wells were all within WHO standard. A high value of 24 mg/l and 25 mg/l for Nitrate was recorded in Saminaka Road and Danfili. An indication of contamination during the rainy season indicates surface-groundwater intrusion (influx). The results of the bacteriological analysis indicated that most wells sampled have a range of 1 cfu/100 ml to 7 cfu/100 ml with Danfili Mani having the highest value (7 cfu/100 ml) which make it unsaved (not Potable). 展开更多
关键词 TEMPORAL CHANGE Analysis GROUNDWATER Physiochemical Bacteriological Quality
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Quality Analysis and Evaluation of Different Peach Varieties 预览
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作者 Huihe LI 《农业生物技术:英文版》 CAS 2020年第2期92-96,共5页
[Objectives] Comprehensive evaluation was made on five peach varieties,in order to select the best varieties.[Methods] With Tongnan century peach,Chengdu Diao Baifeng,Chengdu ball peach,Wujian yellow peach and Wujian ... [Objectives] Comprehensive evaluation was made on five peach varieties,in order to select the best varieties.[Methods] With Tongnan century peach,Chengdu Diao Baifeng,Chengdu ball peach,Wujian yellow peach and Wujian flat peach as research objects,the sensory quality indicators including single fruit weight,fruit shape index and hardness and nutritional quality indicators including soluble solids,total sugar,organic acid,sugar-acid ratio and vitamin C were comprehensively evaluated.[Results] The single fruit weights of different peach varieties ranked as ball peach > century peach > Diao Baifeng > yellow peach > flat peach;fruit firmness followed an order of yellow peach > flat peach > century peach > ball peach > Diao Baifeng;the fruit shape index ranked as yellow peach > ball peach > century peach > Diao Baifeng > flat peach;the contents of soluble solids showed an order of century peach > yellow peach > ball peach > Diao Baifeng > flat peach;the total sugar contents followed an order of century peach > ball peach > Diao Baifeng > yellow peach > flat peach;the organic acid contents ranked as by ball peach > Diao Baifeng > century peach > flat peach > yellow peach;the sugar-acid ratios exhibited an order of yellow peach > century peach > Diao Baifeng > ball peach > flat peach;and the vitamin C contents followed an order of flat peach > Diao Baifeng > century peach > yellow peach > ball peach.Comprehensive evaluation was performed using the rationality-satisfaction degree multiple value theory,and the results showed that the synthesized rationality-satisfaction degree values ranked as yellow peach > century peach > Diao Baifeng > ball peach > flat peach.[Conclusions] Among the five peach varieties in this study,the yellow peach from Wujian town of Yongchuan District was the best,followed by century peach ranking second. 展开更多
关键词 PEACH Sensory quality Nutritional Quality OVERVIEW
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Applying multivariate statistics for identification of groundwater chemistry and qualities in the Sugan Lake Basin, Northern Qinghai-Tibet Plateau, China
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作者 XIANG Juan ZHOU Jun-ju +6 位作者 YANG Jun-cang HUANG Mei-hua FENG Wei LI Qiao-qiao XUE Dong-xiang ZHAO Ya-ru ZHU Guo-feng 《山地科学学报:英文版》 SCIE CSCD 2020年第2期448-463,共16页
The Sugan Lake Basin is located in the inland arid region of northwestern China,in which groundwater is of great significance to human and ecology.Therefore,it is necessary to understand the chemical characteristics a... The Sugan Lake Basin is located in the inland arid region of northwestern China,in which groundwater is of great significance to human and ecology.Therefore,it is necessary to understand the chemical characteristics and quality of groundwater in the basin.Based on samples collected from 35 groundwater wells in Sugan Lake Basin,the spatial distribution characteristics of groundwater chemistry,main hydrogeochemical processes and groundwater quality have been discussed in this paper by using the multivariate statistics and hydrochemistry analysis methods.The results showed that the groundwater is weakly alkaline,and its total dissolved solid(TDS)and total hardness(TH) are high,with the average values of 1244.03 mg/L and 492.10 mg/L,respectively.The types of groundwater are mainly HCO_3~--SO_4~(2-)-Ca~(2+)type in the runoff area and Cl~--SO_4~(2-)-Na~+type in the catchment area.Rock weathering and ion exchange are the main controlling factors of regional groundwater chemistry,followed by evaporative crystallization,and human activities have less impact on groundwater.The spatial difference of groundwater quality is obvious,the water quality of the catchment area is not suitable for drinking,and the suitability for plant growth is also poor.The groundwater in the runoff area can be used for drinking,but the hardness is slightly higher,which is more suitable for ecological purpose. 展开更多
关键词 HYDROCHEMISTRY GROUNDWATER Water quality assessment Sugan Lake Basin Water quality TIBET
Pre- and Post-Slaughter Factors Influencing Hide and Skin Quality in West Shewa Zone, Ethiopia 预览
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作者 Mitiku Eshetu Ewunetu Bekele Yosef Tadesse 《动物科学期刊(英文)》 2020年第1期162-181,共20页
Ethiopia has high livestock population and hence has high potential for hide and skin production. Likewise, in west Shewa Zone of the country there is high hide and skin production. But hides and skins are affected by... Ethiopia has high livestock population and hence has high potential for hide and skin production. Likewise, in west Shewa Zone of the country there is high hide and skin production. But hides and skins are affected by different types of defects that hampered effective and efficient utilization of these resources. Therefore, a study was conducted in Bako Tibe and Ilu Gelan districts of west Showa zone with the objectives to assess pre- and post-slaughter defects that influence hide and skin qualities. Primary data were collected from sample household heads, middlemen, butcheries, hotel/restaurants and tanneries using semi-structured interview and direct observations. All middlemen, butchery and hotel/restaurants in the study areas were employed for data collection while households were selected using simple random sampling techniques. Results of the study revealed that all household respondents reported absence of extension services on hide and skin management. The maximum pre-slaughter defect observed by households (87.2%), hotel/restaurants (91.3%), butcheries (93.3%) and middle men (90%) were due to ectoparasites. Out of the respondents 64.6%, 40% and 82.6% of respondents from household, butcheries and hotels/restaurants, respectively were slaughtered animals on the ground without stunning. The maximum post-slaughter defects observed during slaughtering by households (95.4%), hotel/restaurants (87.0%), and butcheries (86.7%) were dirt and flay cut. According to the respondents, 38.5 of the households kept hide and skin on the ground before marketing. It was found that the major post-slaughter defects of hide were flesh remnant (94.3%), dirty (74.3%), corduroying (71.4%), and flay cut (65.7%). Moreover, traditional animal husbandry and slaughtering practices, poor storage and preservation methods of raw hides and skins, the absence of slaughtering facility and extension service exacerbated the problem. Therefore, there is an urgent need for good animal management practices, animal transportation and slaughtering 展开更多
关键词 Animal Transportation CATTLE Defects GOAT QUALITY SHEEP
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智库产品质量标准模型构建研究 预览
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作者 韩瑞珍 邱均平 《重庆大学学报:社会科学版》 CSSCI 北大核心 2020年第2期85-95,共11页
智库产品质量是智库生存和发展的基石,对智库产品质量的控制和管理是智库建设的关键环节;标准化是质量管理的基础和手段,制定和实施智库产品质量标准有利于加强和完善质量管理、有效提升产品质量,并为科学评价提供参考依据,因此构建智... 智库产品质量是智库生存和发展的基石,对智库产品质量的控制和管理是智库建设的关键环节;标准化是质量管理的基础和手段,制定和实施智库产品质量标准有利于加强和完善质量管理、有效提升产品质量,并为科学评价提供参考依据,因此构建智库产品质量标准具有深刻的理论和现实意义。论文首先界定了智库产品,分析了智库产品质量标准的基本内涵;其次采用文献调研、调查问卷、专家访谈等方法明确了智库产品质量标准核心要素;在此基础上遵循四大原则,构建了由环境、资源、过程、成果、影响效果等五要素组成的PRICE"蛛网式"智库产品质量标准模型。 展开更多
关键词 智库 智库产品 质量 质量标准 模型
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设施老汉瓜采后干制技术研究 预览
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作者 杜娟 热比古丽·哈力克 +1 位作者 沙吾提·阿布拉江 廖新福 《农产品加工》 2020年第4期30-32,共3页
以设施老汉瓜为试材,采用不同成熟度、前处理、预处理温度后进行干制,测定含水率、失重率、色差等指标变化。相同的干燥温度、时间条件下,6个成熟度、2种不同的前处理、5种预处理温度的设施老汉瓜的失重率、最终含水率、总色差值在干制... 以设施老汉瓜为试材,采用不同成熟度、前处理、预处理温度后进行干制,测定含水率、失重率、色差等指标变化。相同的干燥温度、时间条件下,6个成熟度、2种不同的前处理、5种预处理温度的设施老汉瓜的失重率、最终含水率、总色差值在干制期内变化不同。结果表明,不同成熟度的设施老汉瓜,干制期的预处理温度、前处理和烘制温度差距,影响老汉瓜在干制过程中水分的散失。采用不同处理方式至完全干燥,可溶性固形物含量11%的设施老汉瓜,瓜干失重率、含水率、瓜干总色差值ΔE变化略慢,较好地保持瓜干的品质,适宜于老汉瓜的加工。 展开更多
关键词 设施老汉瓜 干制 预处理 温度 品质
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Generation of selectable marker-free soft transgenic rice with transparent kernels by downregulation of SSSII-2 预览
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作者 Zhihao Xu Meimei Yu +8 位作者 Youwei Yin Cenwen Zhu Wen Ji Changquan Zhang Qianfeng Li Honggen Zhang Shuzu Tang Hengxiu Yu Qiaoquan Liu 《作物学报:英文版》 CAS CSCD 2020年第1期53-61,共9页
The amylose content(AC)of rice endosperm starch varies from 0 to 35%,and is associated with rice cooking and eating quality.Soft rice has low AC,generally between 6%and 15%,and its eating quality is high whether it is... The amylose content(AC)of rice endosperm starch varies from 0 to 35%,and is associated with rice cooking and eating quality.Soft rice has low AC,generally between 6%and 15%,and its eating quality is high whether it is consumed hot or cold.However,the appearance quality of current soft rice cultivars needs to be improved,especially opaque endosperm.Conventional genetic engineering has improved some agronomic traits of soft rice varieties,but not endosperm appearance.In the present study,a RNAi construct of the soluble starch synthase II-2(SSSII-2)and the hygromycin phosphotransferase(HPT)gene were introduced into an elite japonica rice variety,Kangtiaowuyunjing(KWY8)by co-transformation.Several selectable marker-free(SMF)transgenic lines were obtained,and SSSII-2 expression was significantly downregulated in selected transgenic lines,resulting in lower AC of the endosperm.The physicochemical properties of the transgenic rice kernels,including gel consistency(GC)and rapid visco analyzer(RVA)profile,differed significantly from those of wild-type rice and were similar to those of a soft rice variety,Nanjing 46(NJ46).These findings indicate that the cooking,eating,and processing qualities of transgenic rice are comparable to those of NJ46.However,the transgenic rice endosperm retained a transparent appearance under low-moisture conditions.Thus,SMF SSSII-2 RNAi rice provides a resource for breeding soft rice with transparent endosperm. 展开更多
关键词 Rice(Oryza sativa L.) SSSII-2 RNAi Starch quality SMF transgenic lines
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热除菌对肉鸡品质的影响研究 预览
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作者 杨红 孙群 +3 位作者 胡庆国 李新林 孔玲 汤飞 《安徽农业科学》 CAS 2020年第3期193-196,共4页
为了探索热除菌对肉鸡胴体品质的影响,提高其杀菌效率,对杀菌温度和杀菌时间进行单因素试验,通过测定大肠菌群数及菌落总数来确定这些因素的杀菌效果,同时研究不同处理条件对鸡肉挥发性盐基氮含量、色差、质构等品质的影响。结果表明,经... 为了探索热除菌对肉鸡胴体品质的影响,提高其杀菌效率,对杀菌温度和杀菌时间进行单因素试验,通过测定大肠菌群数及菌落总数来确定这些因素的杀菌效果,同时研究不同处理条件对鸡肉挥发性盐基氮含量、色差、质构等品质的影响。结果表明,经75~79℃的热除菌下处理15 s后的肉鸡胸肌和腿肌中挥发性盐基氮的含量分别为66.50和120.96 mg/kg;肉鸡胸肌的亮度值(ΔL*)为7.42,红度值(Δa*)为-12.09,黄度值(Δb*)为-6.34;肉鸡腿肌的亮度值(ΔL*)为-3.87,红度值(Δa*)为-0.42,黄度值(Δb*)为-1.01;硬度6.577 kg,弹性76.61%,咀嚼性3.351 kg,胶黏性4.373 kg;肉鸡胸肌的大肠菌群数为6.40×10~4 CFU/g,菌落总数为10.70×10~4 CFU/g;肉鸡腿肌的大肠菌群数为1.14×10~4 CFU/g,菌落总数为1.34×10~4 CFU/g。该试验结果表明,75~79℃下杀菌15 s时杀菌效果最好。 展开更多
关键词 热除菌 肉鸡 品质
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Basal internode elongation of rice as affected by light intensity and leaf area 预览
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作者 Xuhua Zhong Kaiming Liang +5 位作者 Bilin Peng Ka Tian Xiaojuan Li Nongrong Huang Yanzhuo Liu Junfeng Pan 《作物学报:英文版》 CAS CSCD 2020年第1期62-70,共9页
Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of bas... Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of basal internodes persists.The objectives of this study were(1)to identify key factors affecting the elongation of basal internodes and(2)to establish a quantitative relationship between basal internode length and canopy indices.An inbred rice cultivar,Yinjingruanzhan,was grown in two split-plot field experiments with three N rates(0,75,and 150 kg N ha−1 in early season and 0,90,and 180 kg N ha−1 in late season)as main plots,three seedling densities(16.7,75.0,and 187.5 seedlings m−2)as subplots,and three replications in the 2015 early and late seasons in Guangzhou,China.Light intensity at base of canopy(Lb),light quality as determined from red/far-red light ratio(R/FR),light transmission ratio(LTR),leaf area index(LAI),leaf N concentration(NLV)and final length of second internode(counted from soil surface upward)(FIL)were recorded.Higher N rate and seedling density resulted in significantly longer FIL.FIL was negatively correlated with Lb,LTR,and R/FR(P<0.01)and positively correlated with LAI(P<0.01),but not correlated with NLV(P>0.05).Stepwise linear regression analysis showed that FIL was strongly associated with Lb and LAI(R2=0.82).Heavy N application to pot-grown rice at the beginning of first internode elongation did not change FIL.We conclude that FIL is determined mainly by Lb and LAI at jointing stage.NLV has no direct effect on the elongation of basal internodes.N application indirectly affects FIL by changing LAI and light conditions in the rice canopy.Reducing LAI and improving canopy light transmission at jointing stage can shorten the basal internodes and increase the lodging resistance of rice. 展开更多
关键词 Internode elongation Leaf area index Light intensity Light quality R/FR Light transmission ratio Leaf N concentration
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《旅行箱包》标准(2018)内容解读
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作者 常生 单学蕾 +3 位作者 李楠 杨兰 孙月 从俊峰 《中国皮革》 CAS 2020年第1期54-57,59,共5页
从规范性引用文件、产品分类、要求和试验方法、检验规则、标志、包装、运输和贮存等方面介绍了QB/T2155-2018《旅行箱包》的内容,并与QB/T 2155-2010《旅行箱包》进行了比较,指出了标准更新内容。并对新标准的实施提出了7点建议。对新... 从规范性引用文件、产品分类、要求和试验方法、检验规则、标志、包装、运输和贮存等方面介绍了QB/T2155-2018《旅行箱包》的内容,并与QB/T 2155-2010《旅行箱包》进行了比较,指出了标准更新内容。并对新标准的实施提出了7点建议。对新标准QB/T 2155-2018的解读有助于旅行箱包生产企业和相关检测机构更好地理解和运用该标准。 展开更多
关键词 旅行箱包 质量 标准 差异 检测
施氮深度对油后直播棉花产量及品质的影响 预览
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作者 李熠 张志刚 周仲华 《湖南农业大学学报:自然科学版》 CAS CSCD 北大核心 2020年第1期7-13,共7页
以湘K25为试验材料,在相同施氮量前提下,设置4个施氮深度处理H1(0 cm)、H2(5 cm)、H3(10 cm)、H4(15 cm),研究不同施氮深度对油后直播棉花品质及产量的影响。结果表明:施氮深度对棉花产量影响显著,对纤维品质影响不显著;施氮深度为10 cm... 以湘K25为试验材料,在相同施氮量前提下,设置4个施氮深度处理H1(0 cm)、H2(5 cm)、H3(10 cm)、H4(15 cm),研究不同施氮深度对油后直播棉花品质及产量的影响。结果表明:施氮深度对棉花产量影响显著,对纤维品质影响不显著;施氮深度为10 cm时,棉花皮棉产量为1354.26 kg/hm^2,比H1、H2、H4处理分别高412.24、218.6、171.3kg/hm^2;吐絮期,H3处理的干物质积累量最大,达13640.8 kg/hm^2;盛铃期,H3处理的叶面积指数仅小于H2处理的;盛铃期,冠层横向、纵向有效光合辐射(PAR)截获率相对合理,获取的冠层光合有效辐射(PAR)较多。综合分析,施氮深度为10 cm时,油后直播棉花的产量和品质均相对较好。 展开更多
关键词 棉花 施氮深度 产量 品质 冠层光合有效辐射 叶面积指数
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钙钼硼肥对花生光合特性及产量品质的影响 预览
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作者 刘娜 曲胜男 +7 位作者 王晓光 谢畅 高世杰 王婧 于海秋 蒋春姬 赵新华 赵姝丽 《沈阳农业大学学报》 CAS CSCD 北大核心 2020年第1期27-34,共8页
辽宁省作为我国花生的主产区之一,普遍存在施肥不均衡的现象,合理配施肥料是提高花生产量和改善花生品质的有效手段。以农花5号为试材,采用大田随机区组试验,在施用一定氮磷钾肥的基础上,设置4个不同钙钼硼肥配比处理:氧化钙75kg·h... 辽宁省作为我国花生的主产区之一,普遍存在施肥不均衡的现象,合理配施肥料是提高花生产量和改善花生品质的有效手段。以农花5号为试材,采用大田随机区组试验,在施用一定氮磷钾肥的基础上,设置4个不同钙钼硼肥配比处理:氧化钙75kg·hm^-2(T1)、氧化钙75kg·hm^-2+钼酸铵7.5kg·hm^-2(T2)、氧化钙75kg·hm^-2+钼酸铵7.5kg·hm^-2+硼酸22.5kg·hm^-2(T3)和不施钙钼硼肥(CK),研究钙钼硼肥的不同配施组合对花生光合生理特性及产量品质的影响。2年的试验结果表明:单施钙肥处理(T1)和钙钼肥配施处理(T2)可以使农花5号花生在结荚期及以后维持较高的叶色值(SPAD值),显著增强开花下针期和结荚期叶片的净光合速率、蒸腾速率、气孔导度以及群体光合势,进而提高花生的百果重、百仁重、单株饱果数和荚果产量,其中以T2处理效果最佳,2年产量分别为6438.24kg·hm^-2和6015.47kg·hm^-2,比对照增产13.6%和6.9%,单施钙肥处理(T1)次之,而钙钼硼配施处理(T3)则表现为较对照群体光合势降低和产量减少,两年分别比对照减产3.65%和14.77%;在花生籽仁品质方面,增施中微肥显著或极显著提高了脂肪、亚油酸和蛋白质含量,显著降低了可溶性糖含量,而对油酸含量的影响不显著,其中T1和T2处理的脂肪含量,T1、T2和T3处理的亚油酸含量,T2处理的蛋白质含量均显著或极显著高于对照,而T2和T3处理的可溶性糖含量极显著低于CK处理,T2处理的各品质指标在3个处理中变化最大,其次为T1和T3处理。 展开更多
关键词 花生 钙钼硼肥 光合特性 产量 品质
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气候变化与农业活动对中国开都河流域下游水质的影响
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作者 巴乌龙 杜鹏飞 +4 位作者 刘铁 包安明 陈曦 刘蛟 秦成新 《地理学报:英文版》 SCIE CSCD 2020年第1期164-176,共13页
In the context of climate change and over-exploitation of water resources,water shortage and water pollution in arid regions have become major constraints to local sustainable development.In this study,we established ... In the context of climate change and over-exploitation of water resources,water shortage and water pollution in arid regions have become major constraints to local sustainable development.In this study,we established a Soil and Water Assessment Tool(SWAT)model for simulating non-point source(NPS)pollution in the irrigation area of the lower reaches of the Kaidu River Basin,based on spatial and attribute data(2010-2014).Four climate change scenarios(2040-2044)and two agricultural management scenarios were input into the SWAT model to quantify the effects of climate change and agricultural management on solvents and solutes of pollutants in the study area.The simulation results show that compared to the reference period(2010-2014),with a decline in streamflow from the Kaidu River,the average annual irrigation water consumption is expected to decrease by 3.84×10^8 m^3 or 8.87%during the period of 2040-2044.Meanwhile,the average annual total nitrogen(TN)and total phosphorus(TP)in agricultural drainage canals will also increase by 10.50%and 30.06%,respectively.Through the implementation of agricultural management measures,the TN and TP in farmland drainage can be reduced by 14.49%and 16.03%,respectively,reaching 661.56 t and 12.99 t,accordingly,and the increasing water efficiency can save irrigation water consumption by 4.41×10^8 m^3 or 4.77%.The results indicate that although the water environment in the irrigation area in the lower reaches of the Kaidu River Basin is deteriorating,the situation can be improved by implementing appropriate agricultural production methods.The quantitative analysis results of NPS pollutants in the irrigation area under different scenarios provide a scientific basis for water environmental management in the Kaidu River Basin. 展开更多
关键词 CLIMATE change AGRICULTURAL management non-point POLLUTANTS SWAT Kaidu River BASIN water quality
Transcriptome and QTL analyses reveal candidate genes for fiber quality in Upland cotton 预览
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作者 Hantao Wang Ruiting Zhang +3 位作者 Chao Shen Ximei Li De Zhu Zhongxu Lin 《作物学报:英文版》 CAS CSCD 2020年第1期98-106,共9页
With increasing demand for high-quality cotton,it is desirable to identify genes involved in fiber development for molecular improvement of cotton.In this study,780 differentially expressed genes(DEGs)were identified ... With increasing demand for high-quality cotton,it is desirable to identify genes involved in fiber development for molecular improvement of cotton.In this study,780 differentially expressed genes(DEGs)were identified in developing fibers at 10 days post-anthesis(DPA)in Gossypium hirsutum acc.DH962 and G.hirsutum cv.Jimian 5 using RNA-seq.Of 15 stable QTL for fiber quality identified in the same two parents in previous studies,4,3,6,1,and 1 QTL were associated with fiber length(FL),fiber strength(FS),micronaire(MIC),fiber elongation(FE)and fiber length uniformity ratio(FU),respectively.Integration of DEGs and QTL allowed the identification of 31 genes in 9 QTL regions,of which 25 were highly expressed in fibers based on the transcriptome datasets and 9 were preferentially expressed in different stages of fiber development.Gh_A01G0453(GhDTX19),Gh_D07G1581 and Gh_D04G0942 were expressed specifically in 5 and 10 DPA fibers,with Gh_D04G0942 showing low expression in other tissues except pistil.Gh_D07G1799(GhGAUT9),Gh_D11G0326(GhVPS29),Gh_D11G0333(GhTCP14),and Gh_D11G0334(GhNRP2)were preferentially expressed in 5 or 10 DPA fibers;Gh_A01G0397(GhABCG10)and Gh_D07G1744 were expressed specifically in 20 and 25 DPA fibers.These results suggest candidate genes for molecular improvement of cotton fiber quality. 展开更多
关键词 Upland cotton Fiber quality RNA-SEQ QTL Candidate genes
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乌头(Aconitum carmichaeli Debx.)的种根质量标准探究
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作者 文秋姝 张亚琴 +2 位作者 王少军 章卉 陈兴福 《分子植物育种》 CAS CSCD 北大核心 2020年第1期302-310,共9页
随着社会进步,人类急性心肌梗死、冠心病、肿瘤、慢性心力衰竭等疾病发生率居高不下,现代医学表明,乌头类产品有治疗心血管疾病、肿瘤、免疫系统疾病、能量代谢等疾病具有广泛的临床意义。乌头产品需求过高但供应不足,生产上为了提高乌... 随着社会进步,人类急性心肌梗死、冠心病、肿瘤、慢性心力衰竭等疾病发生率居高不下,现代医学表明,乌头类产品有治疗心血管疾病、肿瘤、免疫系统疾病、能量代谢等疾病具有广泛的临床意义。乌头产品需求过高但供应不足,生产上为了提高乌头产量,广泛使用化肥及生长调节剂,但是化肥以及生长调节剂的施用会对环境、土壤以及人体产生较大的负面影响。探究乌头种根质量标准,用绿色生产的模式标准提高产量,对满足乌头的市场需求、医疗需求具有重大意义。为解决化肥及调节剂对人类及生态带来的恶劣影响,采用生态有机的方法解决乌头药材的生产需求,以达到提高乌头种根资源利用率,探索出乌头栽培生产中种根的最佳质量等级,制定出乌头生产的最佳种根标准。本研究将乌头的种根分成三个等级,使用单因素随机试验设计进行大田试验,通过相关性分析和灰色关联度分析等方法对产量、药典指标和经济效益指标进行综合评测。在产量水平上分析,大种根的川乌产量最高,中种根的附子产量优势较强。从质量水平分析,发现种根等级仅对新乌头碱和乌头碱含量具有显著影响,对水分、灰分和生物碱总量影响不大。中种根的经济效益最好。通过灰分关联法和DTOPSIS法对乌头的15种性状进行分析,发现中种根的综合性状更优良。建议生产中采用中种根做种,即以9~18 g的种根作为乌头种植的质量等级标准。 展开更多
关键词 乌头(Aconitum carmichaeli Debx) 种根标准 产量 质量 经济效益
石油套管质量评价方法研究 预览
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作者 闫凯 梁剑 +3 位作者 卫栋 韩华刚 余国民 马跃鹏 《机械制造》 2020年第1期83-85,89,共4页
石油套管是油气田开采中重要的物资装备,其质量直接影响油气田的生产安全与开采效率。对石油套管质量评价方法进行研究,优选反映石油套管质量的性能参数,通过归一化处理,结合专家知识,建立评价模型,进而得到石油套管质量的评价结果。将... 石油套管是油气田开采中重要的物资装备,其质量直接影响油气田的生产安全与开采效率。对石油套管质量评价方法进行研究,优选反映石油套管质量的性能参数,通过归一化处理,结合专家知识,建立评价模型,进而得到石油套管质量的评价结果。将所研究的评价方法应用于P110石油套管质量评价中,评价结果准确、直观,方法有效实用。 展开更多
关键词 石油套管 质量 评价
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Land cover change and eco-environmental quality response of different geomorphic units on the Chinese Loess Plateau 预览
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作者 SONG Yongyong XUE Dongqian +3 位作者 DAI Lanhai WANG Pengtao HUANG Xiaogang XIA Siyou 《干旱区科学:英文版》 SCIE CSCD 2020年第1期29-43,共15页
Land cover in the Chinese Loess Plateau has undergone dramatic changes since the late 1980s.Revealing the trend in land cover change and eco-environmental quality response of different geomorphic units in this stage i... Land cover in the Chinese Loess Plateau has undergone dramatic changes since the late 1980s.Revealing the trend in land cover change and eco-environmental quality response of different geomorphic units in this stage is a realistic requirement for promoting sustainable development of the Chinese Loess Plateau.Based on the data of geomorphic units and land cover in 1990,2000,2010 and 2018 of the Chinese Loess Plateau,we studied the trend of land cover change and eco-environmental quality response of different geomorphic units by using a significance index of land cover change,a proportion index of land cover change and an eco-environmental response model.The results indicated that from 1990 to 2018,the areas of forestland and construction land substantially increased,whereas those of cropland,grassland,wetland and unused land considerably decreased.Land cover change exhibited large geomorphic differences,and the main conversion of land cover was from cropland into other land types.Unstable trend of land cover change in the loess tablelands and sandy loess hills declined,whereas the unstable trends in the other geomorphic units enhanced.Eco-environmental quality varied among different geomorphic units.The expansion of construction land and degradation of forestland,grassland and wetland resulted in the deterioration of eco-environmental quality.The conversion of cropland and unused land into forestland and grassland,and the conversion of grassland into forestland were the main factors that drove the improvement of eco-environmental quality.The findings of this study may provide theoretical reference and support decision making for the optimization of land use structure and the improvement of eco-environmental quality on the Chinese Loess Plateau. 展开更多
关键词 CROPLAND DEGRADATION eco-environmental quality index GRASSLAND human activity unused land relative ecological value
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不同干燥方式对樱桃果粉品质的影响 预览
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作者 刘岩龙 张彩丽 +3 位作者 李婷婷 丛婷玉 徐琳琳 贡汉生 《食品研究与开发》 CAS 北大核心 2020年第7期26-30,共5页
采用热风干燥、真空冷冻干燥、真空干燥3种干燥方式制备樱桃果粉,比较不同干燥方式对果粉水分含量、溶解性、流动性、色度、花色苷与多酚含量、抗氧化能力等理化品质的影响。结果表明:真空冷冻干燥的樱桃果粉水分含量(4.46%)最低,溶解性... 采用热风干燥、真空冷冻干燥、真空干燥3种干燥方式制备樱桃果粉,比较不同干燥方式对果粉水分含量、溶解性、流动性、色度、花色苷与多酚含量、抗氧化能力等理化品质的影响。结果表明:真空冷冻干燥的樱桃果粉水分含量(4.46%)最低,溶解性(52.36%)最好,色泽最接近樱桃的色泽,花色苷含量(5.85 mg/g)和多酚含量(2.13 mg/g)最高,抗氧化能力和清除自由基能力最好,但是流动性最差。热风干燥的樱桃果粉堆积密度(0.45 g/mL)最大,休止角(38.36°)最小,流动性最好。总之,干燥方式对樱桃果粉品质的影响较大,考虑樱桃果粉的理化品质,真空冷冻干燥更适合用于生产高品质樱桃果粉。 展开更多
关键词 樱桃 果粉 干燥方式 品质 理化性质
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品味稻米 预览
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作者 沈希宏 《中国稻米》 2020年第1期102-104,共3页
以一位稻米从业者的感想出发,对我国稻米的地位、历史文化、产量、品质、市场反应等进行了简要描述和讨论。期望能更广泛地来尊敬稻米、更大角度来品味稻米。
关键词 稻米 产量 品质 品味
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不同部位西门塔尔杂交黄牛肉干品质差异分析 预览
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作者 张丽萍 柳艳霞 +4 位作者 赵改名 祝超智 李苗云 贝翠平 韩广星 《肉类研究》 北大核心 2020年第2期7-12,共6页
为研究不同部位牛肉品质的差异,选取西门塔尔杂交黄牛的臀肉、肩肉、黄瓜条、米龙、霖肉5个部位,通过测定出品率、嫩度、风味、色泽和感官品质等指标,探讨部位对黄牛肉干品质的影响规律。结果表明:以米龙制备的黄牛肉干出品率、水分含... 为研究不同部位牛肉品质的差异,选取西门塔尔杂交黄牛的臀肉、肩肉、黄瓜条、米龙、霖肉5个部位,通过测定出品率、嫩度、风味、色泽和感官品质等指标,探讨部位对黄牛肉干品质的影响规律。结果表明:以米龙制备的黄牛肉干出品率、水分含量和水分活度均显著高于其他部位黄牛肉干(P<0.05),且核磁共振信号强度较大;黄牛肉干的亮度值表现为肩肉>黄瓜条>米龙>霖肉>臀肉,以米龙制备的黄牛肉干的红度值(5.76)和黄度值(10.23)均为最大;以黄瓜条和米龙制备的黄牛肉干挥发性风味差异较小,以肩肉制备的黄牛肉干挥发性风味与其他4个部位黄牛肉干差异较大;根据主成分分析和聚类分析得出各指标权重,出品率权重较大,以米龙制备的黄牛肉干出品率最高,因此米龙较适合加工成牛肉干。 展开更多
关键词 胴体部位 牛肉干 品质特征 主成分分析 聚类分析
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