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Root distribution and influencing factors of dry-sowing and wet-growing cotton plants under different water conditions
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作者 DING Yu ZHANG Jianghui +4 位作者 BAI Yungang LIU Hongbo ZHENG Ming ZHAO Jinghua XIAO Jun 《排灌机械工程学报》 CSCD 北大核心 2023年第10期1073-1080,共8页
To study the effect of soil water and salt environment factors on the root growth of cotton under different moisture control,three different emergence water volumes(60,105,and 150 m^(3)/hm^(2)),two different frequenci... To study the effect of soil water and salt environment factors on the root growth of cotton under different moisture control,three different emergence water volumes(60,105,and 150 m^(3)/hm^(2)),two different frequencies(high frequency and low frequency)and one double film cover winter irrigation control treatment(CK:2250 m^(3)/hm^(2))were set up to analyze the spatial distribution patterns of soil water and salt environment and root density in dry sown and wet emerged cotton fields under diffe-rent moisture control conditions.The results show that the soil water content and water infiltration range gradually become larger with the increase of seedling water quantity,and the larger the seedling water quantity,the higher the soil water content.With the same seedling water quantity,the soil water content of the high-frequency(HF)treatment becomes obviously larger.The soil conductivity of each treatment tends to decrease gradually with the increase of seedling water and drip frequency,among which the distribution of soil conductivity of S6 treatment is closest to that of CK.With the increase in soil depth,the soil conductivity tends to increase first and then decrease.Compared with the low-frequency(LF)treatment,the high-frequency treatment shows a significantly deeper soil salt accumulation layer.The root length density(RLD)of cotton gradually increases with the amount of seedling water and the frequency of dripping.The soil layer of root distribution gradually deepens with the amount of seedling water in the vertical direction,and the RLD value in the horizontal direction is significantly greater in the mulched area than that in the bare area between films.This research can serve as a solid scientific foundation for the use of dry sowing and wet emergence techniques in cotton fields in southern Xinjiang. 展开更多
关键词 COTTON double film mulching dry sowing and wet germination moisture regulation water and salt distribution root distribution cotton double film mulching dry sowing and wet germination moisture regulation water and salt distribution root distribution
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Two stages power generation test of the hot dry rock exploration and production demonstration project in the Gonghe Basin,northeastern Qinghai-Tibet plateau,China
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作者 Er-yong Zhang Dong-guang Wen +24 位作者 Gui-ling Wang Xian-peng Jin Lin-you Zhang Hai-dong Wu Wen-shi Wang Cheng-ming Ye Wei Weng Kuan Li Jin-sheng Wu Xian-chun Tang Chong-yuan Zhang Qing-da Feng Sheng Lian Li-sha Hu Gui-lin Zhu Xing-long Xie Bin Wu Dan Wang Xue Niu Zhao-xuan Niu Dong-lin Liu Hui Zhang Wen-hao Xu Shu-qing Yao Li Yang 《China Geology》 CAS CSCD 2024年第3期409-421,共13页
The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in eff... The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in efficient drilling and completion,reservoir construction,and fracture simulation.In 2019,China Geological Survey(CGS)initiated a demonstration project of HDR exploration and production in the Gonghe Basin,aiming to overcome the setbacks faced by HDR projects.Over the ensuing four years,the Gonghe HDR project achieved the first power generation in 2021,followed by the second power generation test in 2022.After establishing the primary well group in the initial phase,two directional wells and one branch well were drilled.Noteworthy progress was made in successfully constructing the targeted reservoir,realizing inter-well connectivity,power generation and grid connection,implementing of the real-time micro-seismic monitoring.A closed-loop technical validation of the HDR exploration and production was completed.However,many technical challenges remain in the process of HDR industrialization,such as reservoir fracture network characterization,efficient drilling and completion,multiple fracturing treatment,continuous injection and production,as well as mitigation of induced seismicity and numerical simulation technology. 展开更多
关键词 Power generation Hot dry rock(HDR) Enhanced geothermal system(EGS) Genesis mechanism Gonghe Basin directional drilling Reservoir construction Circulation test Induced seismicity Clean energy exploration engineering
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Effects of Direct Sowing under Mulch-Based Cropping System (DMC) on Cotton and Maize Yield and Chemical Characteristics of Ferruginous Soil (Lixisoil) in the South Sudan Area of Burkina Faso
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作者 Adama Ouattara Bazoumana Koulibaly +4 位作者 Déhou Dakuo Kalifa Coulibaly Pascal Bazongo Oula Traore Hassan Bismarck Nacro 《Open Journal of Soil Science》 2021年第6期352-365,共14页
To better understand the effects of direct sowing under mulch-based cropping system (DMC) in Burkina Faso’s cotton production systems, randomized blocks of Fisher experimental design were implemented at Farako-B<s... To better understand the effects of direct sowing under mulch-based cropping system (DMC) in Burkina Faso’s cotton production systems, randomized blocks of Fisher experimental design were implemented at Farako-B<span style="white-space:nowrap;">a</span> research station from 2010 to 2019. The study was conducted on lixisoil to evaluate DMC effects on biomass production, crops yields and soil chemical properties in a maize and cotton rotation system associated with cover crop. Conventional tillage and direct seeding without cover crop were compared to DMC under <em>B</em>. <em>ruziziensis</em> (GERM. & EVRARD), DMC under <em>B</em>. <em>ruziziensis</em> + <em>M</em><em>.</em> <em>cochinchinensis</em> mulch and DMC under <em>C. juncea</em> (L.) mulch used in association with maize. Biomass production, crop yields and soil chemistry were evaluated. Results showed that over 10 years, no-till with or without a cover crop provided cotton seed and maize yields that were statistically equivalent to the tillage commonly practiced by farmers. Cover crop has allowed increasing the biomass production compared to Conventional Tillage and Direct Seeding. Maize yield has not varied significantly with the cover crop. After 10 years of maize and cotton rotation, the improvement raised from +27% to +38% for organic matter and from +15% to +29% for nitrogen with DMC including legumes such as <em>M. cochinchinensis</em> and <em>C. juncea</em> compared to Conventional Tillage on 0 - 5 cm depth. No significant differences were found on soil pH like P<sub>2</sub>O<sub>5</sub> and K<sub>2</sub>O content. Although DMC with <em>C. juncea</em> used as cover crop did not provide the best biomass production, it contributes to increase nitrogen and organic matter and presents better mineral balances in 10 years of rotation. The 5 - 10 cm and 10 - 20 cm were little influenced by DMC systems. 展开更多
关键词 Cover Crop Tillage direct sowing under Mulch-Based Cropping System Crop Rotations Soil Characteristic Leguminous
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Influence of Seed Priming on Performance and Water Productivity of Direct Seeded Rice in Alternating Wetting and Drying 被引量:5
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作者 Hafeez Ur REHMAN Muhammad KAMRAN +2 位作者 Shahzad Maqsood Ahmed BASRA Irfan AFZAL Muhammad FAROOQ 《Rice science》 SCIE CSCD 2015年第4期189-196,共8页
Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated t... Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying (DSR-AWD) in comparison with direct seeded rice at field capacity (DSR- FC). Seed priming treatments were osmo-priming with KCI (2.2%), CaCI2 (2.2%) and moringa leaf extracts (MLE, 3.3%) including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with CaCI2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with CaCI2 in DSR- AWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or CaCI2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or CaCI2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation. 展开更多
关键词 crop establishment grain filling rate seed priming water productivity YIELD direct seededrice alternating wetting and drying grain quality
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Effect of Sowing Rate on Agronomic Traits of Sorghum (Sorghum bicolor Moench) in Southern Kyushu, Japan 被引量:2
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作者 Sachiko Idota Yasuyuki Ishii +1 位作者 Mayumi Izu Yukistugu Nishimura 《Agricultural Sciences》 2016年第5期308-314,共7页
Newly released sudangrass-type sorghum cv. “Tarzan” was bred for use as a bioenergy-resource feedstuff in Germany. Since the genotype was collected at a high altitudinal site in the Central Africa continent, its ear... Newly released sudangrass-type sorghum cv. “Tarzan” was bred for use as a bioenergy-resource feedstuff in Germany. Since the genotype was collected at a high altitudinal site in the Central Africa continent, its early growth is vigorous at low temperature. As vigorous growth at low temperature is derived from high tillering ability, the sowing rate of this genotype should be reduced from the ordinary rate for sorghum. Thus, in the present study, the optimal sowing rate of cv. “Tarzan” in southern Kyushu was determined by the effect of sowing rate at 0.5, 1.0, and 1.5 g·m<sup>-2</sup>, designated as low (L), middle (M), and high (H) levels, respectively, on growth habit compared with the normal sudangrass cultivar “Roll-king II”. Early growth was retarded by heavy precipitation in June, after which the growth was comparable for the two genotypes. Dry matter yield of “Tarzan” increased with higher sowing rate;the H level yield was 1298 g·m<sup>-2</sup>, and the yield was not adversely affected by the humidity and heat in the summer growing season, compared with “Roll-king II”. This suggests that “Tarzan” can adapt to the humid, hot climate in southern Kyushu, and the optimum sowing rate of “Tarzan” should be as low as 1.0 - 1.5 g·m<sup>-2</sup>, which is less than one-fifth to one-third that of forage sudangrass grown in the region. 展开更多
关键词 dry Matter Yield GENOTYPE Sorghum bicolor sowing Rate
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Nutrient deficiency limits population development,yield formation,and nutrient uptake of direct sown winter oilseed rape 被引量:12
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作者 WANG Yin LIU Tao +3 位作者 LI Xiao-kun REN Tao CONG Ri-huan LU Jian-wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第4期670-680,共11页
Direct-sowing establishment method has great significance in improving winter oilseed rape(Brassica napus L.) production and guaranteeing edible oil security in China. However, nutrient responses on direct sown wint... Direct-sowing establishment method has great significance in improving winter oilseed rape(Brassica napus L.) production and guaranteeing edible oil security in China. However, nutrient responses on direct sown winter oilseed rape(DOR) performance and population development dynamic are still not well understood. Therefore, five on-farm experiments were conducted in the reaches of the Yangtze River(RYR) to determine the effects of nitrogen(N), phosphorus(P), and potassium(K) deficiencies on population density, dry matter production, nutrient uptake, seed yield, and yield components of DOR plants. Four fertilization treatments included the balanced NPK application treatment(NPK, 180 kg N, 39.3 kg P, 100 kg K, and 1.8 kg borax ha–1) and three nutrient deficiency treatments based on the NPK treatment, i.e., –N, –P, and –K. The results indicated that DOR population density declined gradually throughout the growing season, especially at over-wintering and pod-development stages. Nutrient deficiency decreased nutrient concentration in DOR plants, limited dry matter production and nutrient uptake, and thereby exacerbated density reduction during plants growth. The poor individual growth and reduced population density together decreased seed yield in the nutrient deficiency treatment. Averaged across all the experiments, seed yield reduced 61% by N deficiency, 38.3% by P deficiency, and 14.4% by K deficiency. The negative effects of nutrient deficiency on DOR performances followed the order of –N–P–K, and the effects were various among different nutrient deficiencies. Although N deficiency improved DOR emergence, but it seriously limited dry matter production and nutrient uptake, which in turn led to substantial plants death and therefore resulted in a very low harvested density. The P deficiency significantly reduced initial density, limited plants growth, and exacerbated density reduction. The K deficiency mainly decreased individual growth and yield, but did not affect density dynamic. Our results highlighted the importance of balanced NPK application in DOR production, suggesting that management strategy of these nutrients should be comprehensively considered with an aim to build an appropriate population structure with balanced plant density and individual growth. 展开更多
关键词 oilseed rape(Brassica napus L.) direct-sowing nutrient deficiency population density seed yield yield components nutrient uptake
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Chemical Weeding in Dry Direct Seeding Fields of Single Cropping Middlelate Rice
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作者 Liu Huaizhen Li Kanghuo +5 位作者 Huang Qing Lu Xiuming Zhang Bin Li Huifen Zou Jixiang Zhou Shaochuan 《Plant Diseases and Pests》 CAS 2014年第3期34-38,共5页
Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide( pretilachlor + bensulfuron-methyl,Yang... Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide( pretilachlor + bensulfuron-methyl,Yangguo and butachlor),and the sub-treatment was application method( soil treatments,seedling treatment and integrated treatment). The results showed that 80 g pretilachlor + bensulfuron-methyl( 36% pretilachlor + 4% bensulfuron-methyl) diluted with 50 kg water could be sprayed or 200 g Yangguo( 23. 9% butachlor + 1. 1% bensulfuron-methyl) mixed with 15 kg sandy soil could be broadcasted per 667 m2 on the sowing day or the second day under moist condition of soil,which could effectively control weeds in dry direct seeding fields of single cropping middle-late rice. 展开更多
关键词 Single cropping middle-late rice dry direct seeding field Chemical weeding
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基于四行精密播种的玉米直播机设计与试验
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作者 赵会娟 尹小定 池成忠 《农机化研究》 北大核心 2024年第1期141-145,共5页
为了解决播种玉米种子精度低的问题,设计了一款基于四行精密播种的玉米直播机,可实现玉米种子快速、精准播种。试验表明:该玉米直播机移动性能好、播种速度快、种植深度和每穴种子数量更加准确,封土情况也大幅改善,符合设计需求,具有较... 为了解决播种玉米种子精度低的问题,设计了一款基于四行精密播种的玉米直播机,可实现玉米种子快速、精准播种。试验表明:该玉米直播机移动性能好、播种速度快、种植深度和每穴种子数量更加准确,封土情况也大幅改善,符合设计需求,具有较高的可靠性和可行性。 展开更多
关键词 玉米 四行精密播种 直播机 快速 精准
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播种量对滨海稻区水稻机械旱直播产量、米质及经济效益的影响
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作者 王柏秋 王宇 王诗宇 《北方水稻》 CAS 2024年第1期8-11,38,共5页
为了完善滨海稻区水稻机械旱直播稻高产栽培技术体系,保证产量米质同时尽量降低农业成本、降低劳动强度,提高农业生产效率、经济效益,为直播稻未来在滨海稻区发展提供理论依据。采用田间对比试验方法,研究了不同播种量对滨海稻区水稻机... 为了完善滨海稻区水稻机械旱直播稻高产栽培技术体系,保证产量米质同时尽量降低农业成本、降低劳动强度,提高农业生产效率、经济效益,为直播稻未来在滨海稻区发展提供理论依据。采用田间对比试验方法,研究了不同播种量对滨海稻区水稻机械旱直播产量、米质及经济效益的影响,探索滨海稻区水稻机械旱直播最佳播种量。结果表明,播种量为97.5 kg/hm^(2)机械旱直播产量最高,加工品质较好,但稻米营养品质及食味值略低于播种量为120 kg/hm^(2);水稻机械旱直播比机插秧分别减产2.13 t/hm^(2)、1.76 t/hm^(2)、2.05 t/hm^(2),但效益比机插秧分别增加了0.144万元/hm^(2)、0.218万元/hm^(2)、0.118万元/hm^(2),处理2比处理1、3分别增加0.074万元/hm^(2)、0.100万元/hm^(2)。 展开更多
关键词 播种量 滨海稻区 水稻机械旱直播 产量 米质 经济效益 影响
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化肥优化减施对麦茬旱直播稻强、弱势粒食味与营养品质的影响
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作者 刘奇华 孙召文 +1 位作者 尹秀波 郑崇珂 《河南农业科学》 北大核心 2024年第6期27-36,共10页
以常规施肥处理(F0,施N 350 kg/hm^(2)、P_(2)O_(5)135 kg/hm^(2)、K_(2)O 135 kg/hm^(2))为对照,研究不同化肥优化减施处理(F1:施N 280 kg/hm^(2)、P_(2)O_(5)108 kg/hm^(2)、K_(2)O 135 kg/hm^(2);F2:施N 210 kg/hm^(2)、P_(2)O_(5)81... 以常规施肥处理(F0,施N 350 kg/hm^(2)、P_(2)O_(5)135 kg/hm^(2)、K_(2)O 135 kg/hm^(2))为对照,研究不同化肥优化减施处理(F1:施N 280 kg/hm^(2)、P_(2)O_(5)108 kg/hm^(2)、K_(2)O 135 kg/hm^(2);F2:施N 210 kg/hm^(2)、P_(2)O_(5)81 kg/hm^(2)、K_(2)O 135 kg/hm^(2);F3:施N 140 kg/hm^(2)、P_(2)O_(5)54 kg/hm^(2)、K_(2)O 135 kg/hm^(2))对麦茬旱直播稻强、弱势粒食味与营养品质的影响,以期为直播稻优质高产施肥管理提供参考。结果表明,各化肥优化减施处理总体上均显著提高了直播稻强、弱势粒崩解值和峰值黏度,改善了食味品质,F1、F2、F3处理强势粒的崩解值分别比F0处理显著提高8.35%、7.65%、9.78%,F1、F3处理弱势粒的崩解值分别比F0处理显著提高13.25%、11.13%。各化肥优化减施处理总体上均显著降低了强、弱势粒中组氨酸、脯氨酸及锰含量,总体上均显著提高了强、弱势粒中酪氨酸、精氨酸、赖氨酸含量和弱势粒中铜、锌含量,另外,F1处理还显著提高弱势粒中铁含量,F2处理显著提高强势粒中铁、铜含量及强、弱势粒中钙含量。与F0处理相比,F1、F2、F3处理强势粒的酪氨酸含量分别显著提高100.28%、44.76%、41.08%,弱势粒的酪氨酸含量分别显著提高85.21%、61.64%、22.47%;F1、F2、F3处理强势粒的赖氨酸含量分别显著提高28.87%、27.32%、70.62%,F1和F3处理弱势粒的赖氨酸含量分别显著提高27.23%、39.44%;F1、F2、F3处理强势粒的精氨酸含量分别显著提高6.54%、11.84%、2.18%,弱势粒的精氨酸含量分别显著提高32.83%、33.59%、23.02%。与F0处理相比,F1处理弱势粒铁含量显著提高27.16%,F1、F2、F3处理弱势粒锌含量分别显著提高18.86%、6.56%、3.39%,F1、F2、F3处理弱势粒铜含量分别显著提高2.49%、2.95%、3.11%。综上,化肥优化减施在提高强、弱势粒食味品质的同时,可以改善营养品质,总体上以F1处理最优。 展开更多
关键词 水稻 化肥 优化减施 旱直播 强势粒 弱势粒 品质
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肥密措施对水直播稻苗期杂草发生及产量的影响
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作者 刘福强 向军 +5 位作者 郑华斌 王慰亲 陈元伟 覃斌 吴文革 唐启源 《中国稻米》 北大核心 2024年第3期48-52,共5页
为明确水分管理方式、施氮量和用种量对水直播稻生长发育特性、产量和苗期稻田杂草发生的影响,于2021年以卓两优1126为试验材料,采用再裂区试验设计,在湖南省浏阳市开展大田试验。以水分管理方式为主区,施氮量为副区,播种量为再副区。... 为明确水分管理方式、施氮量和用种量对水直播稻生长发育特性、产量和苗期稻田杂草发生的影响,于2021年以卓两优1126为试验材料,采用再裂区试验设计,在湖南省浏阳市开展大田试验。以水分管理方式为主区,施氮量为副区,播种量为再副区。水分管理(播种至3叶1心期)设淹水(W1)和湿润(W2)2个处理;施氮量设0 kg/hm^(2)(N0)、150 kg/hm^(2)(N1)和195 kg/hm^(2)(N2)3个处理;播种量设15.0 kg/hm^(2)(D1)、22.5 kg/hm^(2)(D2)和30.0 kg/hm^(2)(D3)3个处理。结果表明,不同水分管理方式间苗期稻田杂草总数差异极显著,而不同施氮量和用种量处理间杂草总数差异不显著。W1处理水稻平均产量为8.5 t/hm^(2),显著高于W2处理;N1和N2处理间水稻平均产量差异不显著,但均显著高于N0处理;水稻产量随着用种量的增加而增加,但不同用种量处理间差异不显著。综上,水稻淹水直播条件下,施氮量为150 kg/hm^(2),播种量为15.0 kg/hm^(2),并于3叶1心期除草1次,可在减少除草剂用量的同时实现水稻增产。 展开更多
关键词 直播稻 水分管理 施氮量 播种量 杂草 产量
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直接肾素抑制剂(DRI)阿利吉仑在慢性肾脏疾病(CKD)中的应用进展 被引量:7
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作者 韩蕊(综述) 叶志斌(审校) 《复旦学报(医学版)》 CAS CSCD 北大核心 2012年第4期422-427,共6页
肾素-血管紧张素系统(renin-angiotensin system,RAS)在慢性肾脏疾病(chronic kidney disease,CKD)的发生、发展过程中起重要作用,目前广泛应用的RAS抑制剂血管紧张素转化酶抑制剂(angiotensin convertingenzyme inhibitor,ACEI)和血管... 肾素-血管紧张素系统(renin-angiotensin system,RAS)在慢性肾脏疾病(chronic kidney disease,CKD)的发生、发展过程中起重要作用,目前广泛应用的RAS抑制剂血管紧张素转化酶抑制剂(angiotensin convertingenzyme inhibitor,ACEI)和血管紧张素受体阻断剂(angiotensin receptor blocker,ARB)类药物不足以完全阻断肾脏局部的RAS激活。近年来研发成功的直接肾素抑制剂(direct renin inhibitor,DRI)阿利吉仑为更有效地阻断RAS系统提供了新的选择,许多基础和临床研究均证实了DRI在保护肾功能方面的独特优势,且耐受性好、安全性高,本文就这些研究作一综述。 展开更多
关键词 肾素-血管紧张素系统(RAS) 直接肾素抑制剂(DRI) 慢性肾脏疾病(CKD) 阿利吉仑
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干血斑中34种苯二氮卓类物质的实时直接分析-串联质谱快速筛查研究
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作者 刘富邦 张瑛 +2 位作者 王继芬 周沛龙 侯晓龙 《分析测试学报》 CAS CSCD 北大核心 2024年第2期309-314,共6页
该文通过优化仪器条件和前处理方法建立了实时直接分析-串联质谱快速筛查干血斑(DBS)中34种苯二氮卓类物质(BZDs)的方法。首先将50μL血液沉积在采血卡上形成DBS,DBS经溶剂充分提取后取上层溶液,使用DART 12Dip-It^(TM)模块进样5μL,在... 该文通过优化仪器条件和前处理方法建立了实时直接分析-串联质谱快速筛查干血斑(DBS)中34种苯二氮卓类物质(BZDs)的方法。首先将50μL血液沉积在采血卡上形成DBS,DBS经溶剂充分提取后取上层溶液,使用DART 12Dip-It^(TM)模块进样5μL,在多反应监测模式下检测。结果表明:选用400℃作为载气加热器温度,以乙酸乙酯-水(体积比3∶1)混合溶剂提取DBS样品,所得响应强度较高且建立的筛查方法选择性良好,无延迟效应影响,除阿地唑仑、奥沙西泮和α-羟基三唑仑外,其他物质的检出限均在5~50 ng/mL。所建方法可在90.3%的阳性检材中成功筛选出BZDs物质,方法快速、简便、有效,适用于服药自杀等类案件中DBS检材的快速筛查检验。 展开更多
关键词 实时直接分析 干血斑 苯二氮卓类物质 快速筛查
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鄂中地区油菜专用肥施用效果
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作者 谷贺贺 方雯 +5 位作者 陈金 李旭春 廖世鹏 杨于雄 任涛 鲁剑巍 《湖北农业科学》 2024年第2期74-78,共5页
为明确油菜(Brassica napus L.)专用肥对鄂中地区直播油菜产量的提升效果,于2019—2021年在湖北省沙洋县开展了连续2年的田间试验,设置了不施肥、常规施肥、宜施壮专用肥和洋丰专用肥4个施肥处理,考察各处理下成熟期油菜产量、地上部生... 为明确油菜(Brassica napus L.)专用肥对鄂中地区直播油菜产量的提升效果,于2019—2021年在湖北省沙洋县开展了连续2年的田间试验,设置了不施肥、常规施肥、宜施壮专用肥和洋丰专用肥4个施肥处理,考察各处理下成熟期油菜产量、地上部生物量、地上部养分含量、地上部养分积累量以及肥料偏生产力等的差异。结果表明,与不施肥对照相比,常规施肥和专用肥处理均能显著提高油菜子产量;与常规施肥相比,专用肥处理总养分投入减少了41.3%,而两者油菜子产量无明显差异。施肥显著增加了油菜地上部生物量,促进了油菜地上部对养分的吸收。油菜专用肥处理显著提高了肥料偏生产力,与常规施肥处理相比,宜施壮专用肥和洋丰专用肥处理平均肥料偏生产力在2019—2020年、2020—2021年分别提高了80.6%和68.2%。综上所述,油菜专用肥在保障油菜高产稳产的同时,提高了肥料利用率。 展开更多
关键词 直播油菜(Brassica napus L.) 油菜专用肥 产量 肥料利用率 鄂中地区
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不同播种量对直播山地油菜农艺性状和产量的影响
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作者 凡迪 陈德珍 +1 位作者 曾兵 冯文豪 《山地农业生物学报》 2024年第3期52-56,68,共6页
为在低纬度高原山区综合评价并推广直播油菜最适宜的播种量和种植密度,研究不同播种量对早熟杂交油菜品种‘黔油早2号’产量及经济性状等的影响。结果表明:(1)‘黔油早2号’油菜生育期、成株率、株高、一次分枝数、主花序荚数、主花序... 为在低纬度高原山区综合评价并推广直播油菜最适宜的播种量和种植密度,研究不同播种量对早熟杂交油菜品种‘黔油早2号’产量及经济性状等的影响。结果表明:(1)‘黔油早2号’油菜生育期、成株率、株高、一次分枝数、主花序荚数、主花序长、单株有效荚数、每角粒数等性状均随着播种量的增加呈下降趋势,油菜倒伏率、分枝高随着播种量的增加呈增加趋势;(2)不同播种量的油菜产量构成因子有较大差异,单位面积有效荚数、千粒重、产量随着播量增加呈现先增后减的趋势;(3)‘黔油早2号’在10月中上旬播种,播种量为200 g/667m^(2)时,油菜生长势较强,单位面积有效角果数最高,产量也最高,可达220.99 kg/667m^(2)。本研究通过对早熟油菜品种生育期、倒伏性、冻害、一致性、株高、主花序长、产量构成因子、产量等全性状对比分析,进一步明确了不同种植密度下直播油菜主要性状的变化趋势,明确了低纬度高海拔山区‘黔油早2号’直播的最佳种植密度,该研究结果对于山地生产条件下科学评价和推荐直播油菜最佳种植密度具有现实意义。 展开更多
关键词 直播山地油菜 播种量 ‘黔油早2号’ 农艺性状 产量
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宣粳糯7号选育及作麦茬稻种植的高产栽培技术
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作者 黄一飞 何小卫 +3 位作者 胡锋 郭静 李慈娟 郭成 《安徽农学通报》 2024年第10期1-4,共4页
本文分析了宣粳糯7号的选育过程及其特征特性,并从机插秧和直播两种栽培模式总结其作为麦茬稻的高产栽培技术。选育方面宣粳糯7号是以宣粳糯1号为母本,粳糯86120-5为父本经过系统选育而成的早熟晚粳糯稻品种,具有耐迟播、抗逆性强和适... 本文分析了宣粳糯7号的选育过程及其特征特性,并从机插秧和直播两种栽培模式总结其作为麦茬稻的高产栽培技术。选育方面宣粳糯7号是以宣粳糯1号为母本,粳糯86120-5为父本经过系统选育而成的早熟晚粳糯稻品种,具有耐迟播、抗逆性强和适应性广等品种特性,适宜机插秧和直播作麦茬稻种植。作麦茬稻高产栽培技术原则是在有足够的有效穗数基础上,促壮秆、成大穗和增粒重,配合病虫草害防治。具体措施包括适时适量播种、科学肥水管理、综合防治病虫草害和适时收获等,机插秧还要求匀栽密植、插足基本苗。目的在于为该品种的推广种植提供参考。 展开更多
关键词 宣粳糯7号 品种选育 麦茬稻 机插秧 直播 适时播种 肥水管理
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Effects of different mechanical direct seeding methods on grain yield and lodging resistance of early indica rice in South China 被引量:10
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作者 WANG Wen-xia DU Jie +6 位作者 ZHOU Yan-zhi ZENG Yong-jun TAN Xue-ming PAN Xiao-hua SHI Qing-hua WU Zi-ming ZENG Yan-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第5期1204-1215,共12页
Direct seeding of rice has become a main planting method due to the low labor input and high economic benefit in South China.Dry direct seeding(DDS)has been widely used for single-season rice planting establishment.Ho... Direct seeding of rice has become a main planting method due to the low labor input and high economic benefit in South China.Dry direct seeding(DDS)has been widely used for single-season rice planting establishment.However,few studies have examined the performance of early-season indica rice under mechanical dry direct seeding.A two-year field experiment was conducted with two indica rice cultivars(i.e.,Zhongjiazao 17 and Zhuliangyou 819)to study lodging characteristics and grain yield formation under DDS,flooded direct seeding(FDS)and wet direct seeding(WDS)patterns.The results showed that the annual grain yield in DDS was higher by 14.42–26.34%for cultivar ZLY819 and 6.64–24.58%for cultivar ZJZ17 than in WDS and FDS,respectively,and these increases were mainly attributed to the improvement of the panicles.The DDS pattern significantly increased the seedling emergence rate of early indica rice cultivars,and increased total dry weight and crop growth rate.Meanwhile,shorter basal internodes,better stem diameter and stem wall thickness and lower lodging index were found in DDS in contrast to FDS and WDS.In particular,DDS improved the stem lodging resistance.Our results suggested that the appropriate direct seeding method was beneficial for improving the grain yield and lodging resistance of early indica rice. 展开更多
关键词 mechanical dry direct seeding early indica rice grain yield lodging resistance South China
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利用熔铁浴高温粗煤气冶炼DRI的能耗估算 被引量:2
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作者 苏亚杰 牛强 +1 位作者 杜英虎 陈寿林 《烧结球团》 北大核心 2020年第6期23-28,共6页
为降低炼铁能耗,本文提出熔铁浴煤制气加热循环还原气生产直接还原铁(DRI)的新工艺,并对过程能耗进行了估算。新工艺流程:DRI炉顶气经除尘、CO变换H2、洗涤降温至25℃后脱S和CO2后,被转化成H2体积分数>90%的循环还原气;利用熔铁浴产... 为降低炼铁能耗,本文提出熔铁浴煤制气加热循环还原气生产直接还原铁(DRI)的新工艺,并对过程能耗进行了估算。新工艺流程:DRI炉顶气经除尘、CO变换H2、洗涤降温至25℃后脱S和CO2后,被转化成H2体积分数>90%的循环还原气;利用熔铁浴产生的1300~1700℃的高温粗煤气加热25℃循环还原气至850℃,使V(H)/V(C)(体积比)>1.3,并将还原气送入竖炉冶炼DRI。能耗估算结果表明:新工艺的能耗为329.4 kg标煤/tDRI;若利用转炉富余热量全流程加入30%DRI用于炼钢,与2018年的全国炼钢平均技术指标相比,其能耗降低225.84 kg标煤/t,能源成本降低459元/t;此外,30%DRI加入转炉炼钢比DRI直接加入电炉的能耗降低135.46 kg标煤/t,能源成本降低162元/t。由于利用了高温粗煤气的显热、压力,新工艺的能耗、排放和成本大幅降低。此外,该工艺可低成本回收纯净CO2,利用绿色H2(核能或可再生电力生产的H2)将CO2合成尿素或甲醇后,可以实现CO2零排放。 展开更多
关键词 熔铁浴煤制气 粗煤气显热 直接还原铁 余热炼铁 氢还原铁
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Evaluation of patients with dry eye disease for conjunctival Chlamydia trachomatis and Ureaplasma urealyticum 被引量:6
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作者 Maha Mohssen Abdelfattah Rania Abdelmonem Khattab +1 位作者 Magda H.Mahran Ebrahim S.Elborgy 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第10期1457-1465,共9页
AIM:To determine the possibility of the development of dry eye disease(DED) as a result of persistent infection with Chlamydia trachomatis and Ureaplasma urealyticum in the conjunctiva of patients.METHODS: This st... AIM:To determine the possibility of the development of dry eye disease(DED) as a result of persistent infection with Chlamydia trachomatis and Ureaplasma urealyticum in the conjunctiva of patients.METHODS: This study was conducted on 58 patients of age range 20-50 y,diagnosed with DED confirmed by Schirmer I test and tear breakup time.The non-dry eye control group included 27 subjects of the same age.Ocular specimens were collected as conjunctival scrapings and swabs divided into three groups: the first used for bacterial culture,the second and third taken to detect Chlamydia trachomatis and Ureaplasma urealyticum by direct fluorescent antibody(DFA) assay and polymerase chain reaction(PCR) method. RESULTS: Chlamydia trachomatis was detected in 65.5% and 76% of DED patients by DFA and PCR methods respectively.Ureaplasma urealyticum was found in 44.8% of DED infected patients using the PCR method.Both organisms were identified in only 37.9% of DED patients found to be infected.Control subjects had a 22%detection rate of Chlamydia trachomatis by DFA assay versus a 7% detection rate by PCR; while Ureaplasma urealyticum was detected in 3.7% of the controls by PCR method.The conjunctival culture revealed that gram positive microorganisms represented 75% of isolates with coagulase negative Staphylococci the most common(50%) followed by Staphylococcus aureus(20%),whereas gram negative microorganisms occurred in 25% of cases,isolating Moraxella spp.as the most frequent organism. CONCLUSION: Our results tend to point out that Chlamydia trachomatis and Ureaplasma urealyticum were detected in a moderate percentage of patients with DED,and could be a fair possibility for its development.PCR is more reliable in detecting Chlamydia trachomatis than DFA technique.The presence of isolated conjunctival bacterial microflora can be of some potential value. 展开更多
关键词 dry eye disease CONJUNCTIVA Chlamydia trachomatis Ureaplasma urealyticum direct fluorescent antibody polymerase chain reaction
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The first power generation test of hot dry rock resources exploration and production demonstration project in the Gonghe Basin,Qinghai Province,China 被引量:6
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作者 Er-yong Zhang Dong-guang Wen +39 位作者 Gui-ling Wang Wei-de Yan Wen-shi Wang Cheng-ming Ye Xu-feng Li Huang Wang Xian-chun Tang Wei Weng Kuan Li Chong-yuan Zhang Ming-xing Liang Hong-bao Luo Han-yue Hu Wei Zhang Sen-qi Zhang Xian-peng Jin Hai-dong Wu Lin-you Zhang Qing-da Feng Jing-yu Xie Dan Wang Yun-chao He Yue-wei Wang Zu-bin Chen Zheng-pu Cheng Wei-feng Luo Yi Yang Hao Zhang En-lai Zha Yu-lie Gong Yu Zheng Chang-sheng Jiang Sheng-sheng Zhang Xue Niu Hui Zhang Li-sha Hu Gui-lin Zhu Wen-hao Xu Zhao-xuan Niu Li Yang 《China Geology》 CAS 2022年第3期372-382,共11页
Hot dry rock(HDR)is a kind of clean energy with significant potential.Since the 1970s,the United States,Japan,France,Australia,and other countries have attempted to conduct several HDR development research projects to... Hot dry rock(HDR)is a kind of clean energy with significant potential.Since the 1970s,the United States,Japan,France,Australia,and other countries have attempted to conduct several HDR development research projects to extract thermal energy by breaking through key technologies.However,up to now,the development of HDR is still in the research,development,and demonstration stage.An HDR exploration borehole(with 236℃ at a depth of 3705 m)was drilled into Triassic granite in the Gonghe Basin in northwest China in 2017.Subsequently,China Geological Survey(CGS)launched the HDR resources exploration and production demonstration project in 2019.After three years of efforts,a sequence of significant technological breakthroughs have been made,including the genetic model of deep heat sources,directional drilling and well completion in high-temperature hard rock,large-scale reservoir stimulation,reservoir characterization,and productivity evaluation,reservoir connectivity and flow circulation,efficient thermoelectric conversion,monitoring,and geological risk assessment,etc.Then the whole-process technological system for HDR exploration and production has been preliminarily established accordingly.The first power generation test was completed in November 2021.The results of this project will provide scientific support for HDR development and utilization in the future. 展开更多
关键词 Hot dry rock directional drilling Reservoir stimulation Microseismic monitoring Organic Rankine cycle(ORC) Power generation test Energy geological survey engineering Gonghe Basin Qinghai Province China
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