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101.
为分析渔业领域授权专利的特点,为进一步优化产业布局、促进渔业知识产权运用、引导产业创新提供借鉴。以中国水产科学研究院为例,采用定量的方法,分析了渔业专利的时间分布、IPC技术类别、主题词、研究领域、法律状态等。研究发现,渔业专利发展可分为3个阶段,分别为缓慢增长期,快速增长期和波动增长期。渔业领域专利在传统水产养殖技术和捕捞方面布局广泛,如水产育种,饲料加工,深水网箱等方面,而在工业化水产养殖技术略显薄弱。中国渔业专利的授权率高于总体专利授权率,但专利成果存在转移转化率低、专利维持年限较短、技术走出去不足等问题。  相似文献   
102.
采用模拟Pb、Cd污染土壤培养法研究了紫茎泽兰在重金属Pb、Cd胁迫下植株不同部位对3种营养元素(N、P、K)吸收的影响。结果表明,紫茎泽兰各组织在Pb胁迫下对N、P的吸收总体上均保持一定的促进作用,对K则表现出一定的抑制效应;Cd胁迫下对N、P有良好的吸收,低浓度Cd促进K的吸收,高浓度则表现出抑制作用。Pb-Cd复合污染胁迫下根茎叶均对N的吸收有一定的促进作用,而对K的吸收有较强的抑制效应。这表明,紫茎泽兰在重金属Pb、Cd胁迫下可通过大量吸收N、P等元素来有效缓解重金属的毒害作用,这可能也是紫茎泽兰能适应高Pb、Cd胁迫的一种耐性机制。  相似文献   
103.
Grouper Epinephelus spp. is one of the most important mariculture fish species in China and South-East Asian countries. The emerging viral diseases, evoked by iridovirus which belongs to genus Megalocytivirus and Ranavirus, have been well characterized in recent years. To date, few data on lymphocystis disease in grouper which caused by lymphocystis disease virus (LCDV) were described. Here, a novel LCDV isolate was identified and characterized. Based on the sequence of LCDV major capsid protein (MCP) and DNA polymerase gene, we found that the causative agents from different species of diseased groupers were the same one and herein were uniformly defined as grouper LCDV (GLCDV). Furthermore, H&E staining revealed that the nodules on the skin were composed of giant cells that contained inclusion bodies in the cytoplasm. Numerous virus particles with >210 nm in diameter and with hexagonal profiles were observed in the cytoplasm. In addition, phylogenetic analysis based on four iridovirus core genes, MCP, DNA polymerase, myristoylated membrane protein (MMP) and ribonucleotide reductase (RNR), consistently showed that GLCDV was mostly related to LCDV-C, followed by LCDV-1. Taken together, our data firstly provided the molecular evidence that GLCDV was a novel emerging iridovirus pathogen in grouper culture.  相似文献   
104.
为了探索樱桃番茄无土栽培在海南热带地区种植效果及植株产量效应,本研究通过增施不同量叶面肥,设计3种处理、3次重复随机试验,并对试验最佳效果的植株产量、株高和茎粗建立相关数学模型。结果表明,增施叶面肥较传统施肥有明显增产效果,平均增产2250 kg/hm2,增产20.2%。而樱桃番茄株高与产量、茎粗与产量具有显著相关性,其模型分别为Y单株产量=(47.92060X株高-24.95763)2 (P= 0.0114<0.05)和Y单株产量=(61.885X茎粗-46.97988)2 (P=0.0372<0.05),符合植株生长趋势变化。因此,在海南开展樱桃番茄无土栽培是可行的,且可以通过调控来调节植株生长情况从而提高产量,增加经济效益。  相似文献   
105.
Nitrous oxide (N2O) fluxes from an apple orchard soil in the semiarid Loess Plateau of China were measured using static chambers from September 2007 to September 2008. In this study, three sites were selected at distance of 2.5 m (D 2.5), 1.5 m (D 1.5), and 0.5 m (D 0.5) from the apple tree row. Nitrous oxide fluxes followed seasonal pattern, with high N2O emission rates occurring in the hot-humid summer and low rates in the cold-dry winter. Pulses of N2O emissions occurred after nitrogen fertilizer application, summer rainfall events, and during freeze-thaw cycles. Annual average N2O emission rates were the highest at D 0.5 site (48.2 ± 39.9 μg N2O m−2 h−1), the lowest at D 2.5 site (31.9 ± 18.2 μg N2O m−2 h−1), and intermediate at D1.5 site (36.8 ± 32.2 μg N2O m−2 h−1), suggesting that N2O emissions from the apple orchard soil increased when the chamber location was closer to the apple tree row. This may be due to the fertilization close to roots in hot and humid season. Over one third (37.1%) of the annual N2O emission occurred in the summer. Annual N2O emissions from the apple orchard soil averaged to 3.22 kg N2O ha−1 year−1. Annual emission factor of the apple orchard from the applied fertilizer (uncorrected for background emission) was 0.658%. This value was nearly a half (53%) of the default value provided by the Intergovernmental Panel on Climate Change for the application of synthetic fertilizers to cropland (1.25%). Therefore, the amount of N2O emissions from the semiarid apple orchard soil could be largely overestimated if no regional-specific factor is used.  相似文献   
106.
Laboratory culture experiments were conducted with common reed (Phragmites australis) to elucidate the role of root exudates on CH4 production in wetland soils as well as the importance of different plant organs as routes of CH4 to the atmosphere. In the 50 d experiment period, root exudates ranged from 0.03 to 1.53 µmolg?1d?1, which increased with reed growth. CH4 production rate of soil was stimulated as root exudates collected was added. CH4 transport capacity rate also increased with plant growth and influenced by light intensity. Root tips were the most important part of controlling diffusion of CH4 into reed shoots, and leave transport accounted for 45.34% of total emissions into the atmosphere.  相似文献   
107.
Lu  M.  Yuan  D.  Li  Q.  Ouyang  T. 《Water, air, and soil pollution》2009,200(1-4):387-397
Water, Air, & Soil Pollution - Central composite design using response surface methodology was employed to optimize soil/liquid ratio (S/L), pH, and incubation time for polycyclic aromatic...  相似文献   
108.

Background, aim, and scope  

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) is one of the most widely used herbicides for broadleaf weed and certain annual grass controls and is popular because of its effectiveness and low cost. Losses of atrazine from agricultural lands into adjacent surface water and underlying groundwater have raised public concerns. Several computer models have been developed for atrazine runoff in watersheds. One limitation for most of these models, however, is that vast amounts of input parameters are required for simulations. These input parameters are sometimes difficult to obtain through the experimental measurements for model calibrations, validations, and applications. Therefore, a need exists to develop a simple and yet a realistic modeling tool that can be used for effectively investigating atrazine dynamics in agricultural soils. This study was designed to meet this need.  相似文献   
109.
闽江口景观资源评价研究   总被引:2,自引:0,他引:2  
闽江口是中国最具景观多样性的河口地区之一,山海川岛的地貌特征,深厚的历史文化底蕴,良好的生态环境,充满活力的现代产业景观以及别具一格的侨乡风貌构成了一幅绚丽多彩的风景画。本文采用VRM系统对闽江口的景观视觉质量进行了评价,十个景观质量评价单元中有九个属A级,一个属B级,可见闽江口地区的景观质量是非常高的。  相似文献   
110.
绿色农药分散剂GCL4-1的结构特征及应用性能研究   总被引:2,自引:0,他引:2  
采用红外光谱、电位滴定、凝胶渗透色谱对改性木质素磺酸钠农药分散剂GCL4-1的分子结构进行了研究,结果表明,GCL4-1分子中磺酸基含量较改性前的木质素磺酸钠LS有明显提高,磺化度从改性前的1.33 mmol/g增加到1.96 mmol/g;其重均分子量为9700,数均分子量为2300。进一步研究了GCL4-1对农药水分散粒剂(WG)应用性能和药效等的影响,发现以GCL4-1作分散剂制备的WG具有良好的润湿性和崩解性,WG热贮前后的悬浮率都超过90%;WG悬浮液分散稳定性优良,2 h后的悬浮液沉淀层厚度仅为0.386 mm,颗粒粒径为7.22 μm。制得的80%烯酰吗啉WG防治黄瓜霜霉病的EC90值为58.32 mg/L,80%氟虫腈WG样品对小菜蛾的LC50值为0.5196 mg/L,室内毒力达到了国外同类制剂最好产品水平。GCL4-1的综合性能达到甚至超过Borregaard公司的Kinsperse126,是一种具有优良性价比的绿色农药分散剂。  相似文献   
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