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1.
0概况巴西联邦共和国,位于南美洲东部.全国总面积851.20万km2,约占南美洲总面积的一半,是南美洲面积最大的国家。总人口为18065.4万人(2004年),也是南美洲人口最多的一个国家,其中55%为白种人,38%为混血种人,葡萄牙语为其官方语言,  相似文献   

2.
在一跃成为玉米多功能收获机销售量全国领先和政府补贴台数领先的企业之后,2008年,山东金亿机械制造有限公司(以下简称"金亿公司")欲继续发力于自走式小麦收获机市场.  相似文献   

3.
1.选好机型 目前,水稻联合收割机机型很多,应按先进适用原则,选择性能好、效率高、适应性强、可靠性好、价格合理的机型.2006年在江西省吉水县推广的机型有丹霞4L-0.5、柳林-160、三联-160和碧浪4L-1.0等.经使用,丹霞4L-0.5型具有体积小、转移方便、适用于山区和种粮大户的特点,每台每季可作业7hm2以上,农民反映较好.柳林-160型具有质量好、功效高、故障少的特点,适应于平原大田块和为其他农户服务用,每台每季作业13hm2以上,深受机手和农民欢迎.  相似文献   

4.
紧急受命 1954年,山西省在文水县南安乡谢家寨村建起了山西省碱地改良站,前苏联专家在视察该改良站土地后提出:对留茬的玉米地,必须先用拖拉机进行深耕(耕深22cm),等过了冬季,才能检验出防治盐碱的效果.在当时,前苏联专家的建议就是最权威的命令,山西省农业厅的领导不敢怠慢,赶紧组织人手、分配任务,由于条件有限,整个晋中地区只有榆次县张庆乡有几台拖拉机,在汾河岸以西还没有一台农业机械.  相似文献   

5.
(本刊讯)天上飞行助威、地上热歌劲舞。10月26日上午,2007年全国农机产品订货交易会暨第十一届中国国际农业机械展览会开幕式在郑州国际会展中心  相似文献   

6.
介绍了Audi(奥迪A6)MOST-BUS结构,传输和工作过程的特点,针对MOST-BUS结构,提出MOST-BUS系统故障诊断的基本思路和环型断裂诊断法.  相似文献   

7.
现阶段,我国制药行业星罗棋布,生产水平良莠不齐,持有生产许可证的生产企业已达6000多家,但其中90%为中小型企业,规模小,技术落后,设备陈旧,产品质量安全亦无保障.针对当前国际上全自动配料设备价格相当昂贵、国内目前同型设备短缺及我国中小企业的实际生产状况,设计并制造了自动控制配料机,该机通过PLC编程实现药品配方原料成分识别、料斗自动旋转、制动和成份称重后的自动倒料过程.介绍了配料机的组成、工作原理以及结构设计过程.  相似文献   

8.
随着浦城县农村经济的快速发展,联合收割机的使用越来越普遍,作为一种致富的工具,联合收割机越来越受到用户的重视和欢迎。但用户在使用联合收割机过程中时常反映"跑粮"(籽粒损失)问题。  相似文献   

9.
高寅 《农村电工》2007,15(7):34-34
2006年8月28日20时10分,一辆装有泥土的翻斗汽车在安徽省宿松某开发区工地卸土时,不慎将一条10 kV高压线挂断,致使县城西南方上千户居民和单位突然断电.由于高压线采用的是绝缘线,车主才幸免于难.  相似文献   

10.
豪丰印象     
5月下旬,正是小麦夏收时节,笔者如约来到位于河南省许昌县张潘镇的河南豪丰机械制造有限公司.10多年前我曾来过当时还是许昌县农机总厂的这家企业,当年的厂长,现任公司董事长刘少林早已等在办公楼前,一口纯正的河南腔,还是那个大嗓门,虽然岁月的沧桑给他增添了些许皱纹,但眼前这个一米八的中原汉子依旧那么豪爽,那么开朗,竟使人看不出多少岁月磨砺的痕迹.在寒暄后的访谈和参观中,一个现代农机具生产企业和它的当家人的形象逐渐在我的脑海中清晰起来.  相似文献   

11.
对饮料中的柠檬黄含量进行了测定和不确定度分析,通过对各影响因素的不确定度评定,试验重复性对饮料中合成着色剂的测量结果不确定度的影响最大,其次是样品处理回收率和标准曲线拟合引入的不确定度对试验结果也有较大的影响。结果表明:饮料中柠檬黄的含量为(103.5?3.5)mgkg,k=2。   相似文献   

12.
Adoption of a new technology, such as irrigation, is a complex phenomenon. Several factors of economic and social nature contribute to the farm-level decisions affecting adoption. In this study, the role played by attitudes of potential adopters towards irrigation and its subsequent adoption on their farm unit was estimated. Two models were estimated, one incorporating only adopters' socio-economic characteristics, and the other, only their attitudes towards irrigation. Results suggest that adopters' attitude, particularly with respect to economic and environmental effects of irrigation, were significant determinants of their decision to proceed with adoption of irrigation, and have a role to play in adoption of irrigation over and above that explained by socio-economic characteristics. In particular, these results suggest that negative perceptions with respect to economics of irrigation and those related to its detrimental impacts on environmental quality, particularly through soil salinity, may be significant deterrents for adoption of irrigation. The study suggests that planning of large scale water development projects, particularly those involving irrigation, must be cognizant of attitudes of potential adopters. Furthermore, during the planning stages, more attention should be paid to the development of proper educational programs, as well as extension packages, to ensure that potential adopters formulate correct attitudes towards the new technology.  相似文献   

13.
数学作为一门基础性学科,在学生的各个学习阶段都起到了不可替代的作用,在工科院校中数学教学的重要性更是升到了一个新的高度。通过数学的学习,可以培养学生的应用能力和探究思维,通过对数学知识的学习和灵活运用,学生的综合能力会得到系统性的提高。对于数学的教学工作,应当做到有针对性、有目标,在教学工作中,充分做到对症下药、有的放矢,让学生通过对数学的学习,提高自身的综合能力,更好地为社会建设贡献力量。  相似文献   

14.
15.
本试验通过沼气燃烧,提高冬季温室温度,促进西红柿生长发育.试验结果表明:增温可有效提高冬季温室温度,为西红柿越冬生产提供良好条件,有利于西红柿植株茎粗增加及果实膨大速率提高;可使西红柿坐果期提前10天左右,采收期延长20天左右,并提早上市.同时,增温可显著提高西红柿产量,亩增产800kg.  相似文献   

16.
分析了四川简阳地区砂岩和土壤中的水分运动特性和砂岩中储存的水分对土壤水分补给量的多少。对当地的砂岩和土壤进行了水分特征曲线的测定试验、入渗试验和蒸发试验,并采用研究中常用模型对试验结果进行了拟合,通过对拟合结果的分析,得出了当地土壤和砂岩的水分特性,总结出了该地区表面土层在缺水时水分很容易被下部砂岩层补给,砂岩中的水分是作物利用的重要水资源的结论。这对于充分利用当地水资源,合理确定类似地质条件地区灌溉定额,解决无灌溉条件丘陵区作物缺水问题,实现农业节水灌溉有一定的参考价值。  相似文献   

17.
Agricultural ecosystems and their associated business and government systems are diverse and varied. They range from farms, to input supply businesses, to marketing and government policy systems, among others. These systems are dynamic and responsive to fluctuations in climate. Skill in climate prediction offers considerable opportunities to managers via its potential to realise system improvements (i.e. increased food production and profit and/or reduced risks). Realising these opportunities, however, is not straightforward as the forecasting skill is imperfect and approaches to applying the existing skill to management issues have not been developed and tested extensively. While there has been much written about impacts of climate variability, there has been relatively little done in relation to applying knowledge of climate predictions to modify actions ahead of likely impacts. However, a considerable body of effort in various parts of the world is now being focused on this issue of applying climate predictions to improve agricultural systems.

In this paper, we outline the basis for climate prediction, with emphasis on the El Niño-Southern Oscillation phenomenon, and catalogue experiences at field, national and global scales in applying climate predictions to agriculture. These diverse experiences are synthesised to derive general lessons about approaches to applying climate prediction in agriculture. The case studies have been selected to represent a diversity of agricultural systems and scales of operation. They also represent the on-going activities of some of the key research and development groups in this field around the world. The case studies include applications at field/farm scale to dryland cropping systems in Australia, Zimbabwe, and Argentina. This spectrum covers resource-rich and resource-poor farming with motivations ranging from profit to food security. At national and global scale we consider possible applications of climate prediction in commodity forecasting (wheat in Australia) and examine implications on global wheat trade and price associated with global consequences of climate prediction.

In cataloguing these experiences we note some general lessons. Foremost is the value of an interdisciplinary systems approach in connecting disciplinary knowledge in a manner most suited to decision-makers. This approach often includes scenario analysis based on simulation with credible models as a key aspect of the learning process. Interaction among researchers, analysts and decision-makers is vital in the development of effective applications — all of the players learn. Issues associated with balance between information demand and supply as well as appreciation of awareness limitations of decision-makers, analysts, and scientists are highlighted. It is argued that understanding and communicating decision risks is one of the keys to successful applications of climate prediction.

We consider that advances of the future will be made by better connecting agricultural scientists and practitioners with the science of climate prediction. Professions involved in decision making must take a proactive role in the development of climate forecasts if the design and use of climate predictions are to reach their full potential.  相似文献   


18.
Pesticides degrade principally through biodegradation processes, whereas antibiotics kill microorganisms or inhibit their growth in soils and thus may affect the fate of pesticides. In this study, the impact of antibiotics on the degradation of atrazine in a sandy soil is investigated in lysimeters over a ninety-day period. Four treatments, monensin, narasin, salinomycin and non-antibiotic, were assigned in triplicate to twelve PVC lysimeters. Both soil and leachate samples were collected and analyzed at predetermined time intervals. In all treatments, atrazine was found to leach down through the soil profiles with the concentration level decreasing with depth, and only trace amounts of atrazine were found in the leachate. However, the statistical analysis of the results showed that all the three antibiotic treatments yielded a significantly slower dissipation of the atrazine level as compared to the non-antibiotic treatment; the mass balance analysis indicated an increased half-life of atrazine in the presence of antibiotics.  相似文献   

19.
北京典型灌区土壤和农产品多氯联苯污染风险评估   总被引:5,自引:0,他引:5  
为明确北京东南郊灌区表层土壤和农作物多氯联苯(PCBs)含量和污染水平以及人体健康风险,2015年在该灌区采集了20个土壤样品和28个作物样品,利用气相色谱-质谱联用仪分析了样品中7大类PCBs含量。研究结果表明,灌区表层土壤PCBs质量比为ND(低于检出限)到0.711 776μg/kg,均值为0.43μg/kg,总体上土壤PCBs含量随污灌历史年限增加而增加。本研究区表层土壤PCBs含量处于较低水平,土壤未受到PCBs污染且其生态风险概率均小于10%。灌区采集的冬小麦籽粒、大葱、茄子、梨、白薯、芥蓝PCBs含量均低于实验检出限,未检出;夏玉米籽粒、菜心和油菜PCBs总量分别为0.17~0.47μg/kg、1.63μg/kg和5.91μg/kg。不同污灌历史年限并未显著影响夏玉米籽粒PCBs含量。本研究区农产品PCBs含量处于较低水平,均低于美国卫生及公共服务部建议限量。采集的土壤和农产品样品仅四氯联苯含量高于实验检出限,能检测出;一氯联苯到三氯联苯和五氯联苯到七氯联苯均低于实验检出限,未检出。本研究中成人和儿童PCBs致癌风险分别为8.49×10-7和4.66×10-7,非致癌风险分别为1.41×10-1和3.88×10-1,均低于US EPA规定限值,说明PCBs未对人群产生明显的健康危害。致癌危害和非致癌危害均以口-作物(玉米和蔬菜)为主,其对人体健康所造成的风险占总个人年风险的比例分别为99.79%~99.95%和99.81%~99.94%。  相似文献   

20.
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