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21.
随着新疆阿克苏地区机采棉面积的激增,棉花质量出现下降,存在颜色级下降、长度偏短、成熟度不够等现象。为全面了解阿克苏地区棉花纤维品质变化情况及成因,阿克苏地区农业农村局组织有关人员深入植棉县(市)种子管理站、种业企业、棉花加工企业、棉纺企业、种植大户开展调研。结合调研分析,认为影响棉花质量的主要因素是品种、种植管理、采收、收购和加工工艺等,并从积极发挥政策引导作用,加大优质棉花品种选育与管理,开展配套生产技术研究与规范棉花种植管理,规范棉花采收、加工行为,强化棉花质量监督检查,合力打造品牌棉花,促进信息互联互通等方面提出了相应对策,以期对提升该地区棉花质量起到指导作用。 相似文献
22.
2011年,在吉林省大安市、洮南市和镇赉县分别进行了大田烤烟,锰、硼、钼、锌和镁肥的施肥量和施用方法的试验研究。试验结果表明:在锰、硼、钼、锌和镁等中微量元素有效含量缺乏的烟田中,增施适量的中微肥,能够促进烤烟的营养均衡并在此基础上促进其生长;能够提高土壤和叶片中相应的中微量元素含量;烤烟的经济效益也随之得到提高。从试验长势看,所有试验中微肥都比对照好,喷施比基施表现要好,基施中硼、钼、锌、镁表现比较好,喷施中硼、钼、镁、钾+钼、钾+锌表现最好;从烘烤质量上看,不论基施的还是喷施的钼都表现得最好。 相似文献
23.
A cobalt-mediated decrease in ethylene production reduced the inhibition of nodulation by nitrate in Vigna radiata (mungbean). Nitrate increased the ethylene production in 5-day-old seedlings, while it caused a reduction in the nodulation
status (nodule number and nodule weight) and nodule efficiency (acetylene reduction activity) in mungbean plants. The application
of cobalt chloride inhibited nitrate-affected ethylene production and also decreased the inhibitory effect of nitrate on nodulation.
The effect of cobalt was most marked on nodule number.
Received: 6 August 1999 相似文献
24.
Ayu-Lana-Nafisyah Endang-Dewi-Masithah Kazumi Matsuoka Mirni-Lamid Mochammad-Amin-Alamsjah Shizuka O-hara Kazuhiko Koike 《Fisheries Science》2018,84(5):877-887
Mangrove forests and adjacent creeks are known to be highly productive estuaries, which are partly supported by benthic microalgae that grow on the sediments. During surveys investigating the microalgal floras of mangrove swamps in the eastern part of Java Island, a mud sample unexpectedly included large numbers of a notorious fish killer, Chattonella-like motile cells, and its resting cysts. These motile cells were established as clonal cultures for further identification and physiological tests. The cysts were examined through palynological and molecular biological means. Identification based on light microscopy and ribosomal RNA gene sequences confirmed that these cells and cysts were Chattonella marina var. marina. While the strains were genetically identical to the temperate strains isolated from Japan and China, temperature experiments showed that the Indonesian strains possessed a high maximum quantum yield of photosystem II even after exposure to 34 °C, a temperature at which the Japanese strain could not survive. Salinity experiments showed adaptation of the strains to a salinity of 15. These findings, together with the discovery of populations of cysts in the mangrove sediment, highlight the tough and unique nature of the Indonesian strains, which are likely adapted to wide fluctuations of temperature and salinity in mangrove swamps, and pose a potential risk to fisheries in Indonesia. 相似文献
25.
试验选取4头安装有永久性瘤胃、十二指肠和回肠瘘管的荷斯坦泌乳奶牛,采用4×4拉丁方试验设计,研究日粮中添加亚油酸(LA)和二十二碳六烯酸(DHA)对瘤胃原虫中奇数碳链脂肪酸和支链脂肪酸的影响.试验结果表明:奇数碳链脂肪酸和支链脂肪酸(OBCFA)是原虫脂肪酸的重要组成部分,与对照组相比,日粮中单独添加LA或DHA对瘤胃原虫中主要OBCFA的含量无显著影响,而当LA和DHA协同添加时C15∶0和C17∶0的含量显著降低(P0.05),但对异构酸和反异构酸的含量无显著影响. 相似文献
26.
Logistic模型模拟乙醇发酵产物动力学 总被引:1,自引:0,他引:1
乙醇发酵产物动力学的研究有助于更好的认识发酵过程,为其工业放大及生产操作条件的优化提供理论基础。基于Logistic方程的菌体生长动力学模型可较好的描述细胞生长期及细胞自身抑制作用,但由于该模型方程中的比例参数与积分常数没有明显的生物学意义,使其应用受到了限制。该文从生物学与化学工程学结合角度对Logistic模型方程重新参数化,将发酵产物乙醇生成动力学与酵母生长动力学方程类比,给出了乙醇浓度的显式函数模型,模型中不再出现酵母菌浓度变量,大大简化了模型,并且赋予参数其物理意义;在研究了以葡萄糖和玉米淀粉为原料乙醇质量浓度、总糖质量浓度在不同底物质量浓度和料液比条件下随发酵时间的变化规律的基础上运用该模型拟合了以葡萄糖和玉米淀粉为原料进行乙醇发酵的试验数据,结果表明:模型值与试验数据具有较好一致性,拟合度均大于0.97,可见该重新参数化的Logistic模型可以描述发酵生产乙醇过程中产物乙醇的动力学行为,具有预测工业上实际发酵过程中乙醇浓度的潜力。 相似文献
27.
This paper presents empirical evidence on the impact of socio-economic factors on the adoption of agroforestry practices in
Cameroon. The analysis uses primary farm-level data collected from June to December 1996. Three major provinces of the country
were covered, namely Centre, Southwest and Northwest Several agroforestry technologies have been promoted among farmers in
the zone, including alley farming, improved fallow, live fencing, cut-and-carry fodder and apiculture. The status of adoption
of each agroforestry practice is described and factors that affect adoption identified. These are gender of farmer, household
family size, level of education, farmer’s experience, membership within farmers’ associations, contact with research and extension,
security of land tenure, agroecological zone, distance of the village from nearest town, village accessibility and income
from livestock. Research findings indicate that since factors affecting farmers’ adoption of agroforestry practices differ
across techniques, generalisation is to be avoided. 相似文献
28.
Dimethylaminopropyl methacrylamide (DMAPMA) was grafted onto PET/wool blend fabrics by continuous UV irradiation. Union dyeing
of the photografted fabrics was investigated using three reactive dyes of α-bromoacrylamide reactive groups. The influence of grafting yield, DMAPMA concentration, NaCl amount, pH value, and dyeing
temperature on the dyeability was evaluated. The dyeability of both PET and wool components was improved significantly by
the DMAPMA photografting and successive reactive dyeing. Although the dyeability of the PET component in the blend substantially
was improved with higher grafting, equal dyeability between PET and wool was difficult to achieve due to more facile grafting
and higher reactivity of the wool component compared with the modified PET component. However, the color fastness of the PET/wool
blend fabric was excellent for all three colors. This study may offer a way to achieve union dyeing of PET/wool blend fabrics. 相似文献
29.
Pavarot Noranarttragoon Yuji Ueda Tsutomu Hattori Takashi Matsuishi 《Fisheries Science》2011,77(4):497-502
The yield-per-recruit (YPR) analysis has been used to assess growth overfishing of exploited fish stocks. Since the ex-vessel
price per weight widely depends on the size of the fish, the result of the YPR does not imply the revenue. The value-per-recruit
(VPR) analysis, which is an economic expansion of the YPR analysis, was conducted for bighand thornyhead Sebastolobus macrochir caught off the Pacific coast of northern Honshu, Japan. The results showed that, for the current age at first capture (t
c = 3), the current fishing mortality (F = 0.12) was close to the optimum level. However, for the current F, optimum t
c in the VPR model was 8 years and would lead to a 47% increase compared to the current revenue. The maximum YPR was obtained
at t
c = 6 years, but the revenue at t
c = 6 only gave a 20% increase in the maximum revenue. The difference was caused by the size dependency of the ex-vessel price
per weight. The VPR model would generate fisheries management plans with both economical and biological consideration and
would help in making general consensus of fisheries management strategies. 相似文献
30.
地方高校要发挥自身优势,自觉为“三农”服务 总被引:3,自引:0,他引:3
在当前教育高速发展的新形势下,地方高校要发挥自身优势,自觉为“三农”服务是高校为地方经济发展服务的延伸和发展。本从三个方面进行阐述,一是高等教育通向农村是实现农业现代化的客观要求;二是通向农村是高等教育自身发展的内在要求;三是提出了高等教育通向农村的对策措施。 相似文献