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1.
[目的]研究秸秆生物反应堆技术的应用对茄子温室内气温和二氧化碳浓度的影响,[方法]以茄子温室为研究对象,通过栽培试验和室内测定分析方法相结合,对玉米秸秆反应堆技术应用过程中的温室内外二氧化碳浓度进行跟踪观测.[结果]秸秆生物反应堆对棚内气温有明显的提高,平均提高1.5-2.3℃,最高可以提高温室温度4℃.应用秸秆生物反应堆可以明显提高棚内二氧化碳浓度.[结论]秸秆生物反应堆技术能够明显改善温室的生态环境,解决日光温室CO<,2>不足的矛盾,为温室蔬菜增产提供基础保证.  相似文献   

2.
[目的]研究精细化气候预测产品的制作方法及效果检验.[方法]以国家地面观测标准资料和来用距离权重插值法获得的二级资料库为依据.建立气候预报模型,集合多种预报方法和人工订正,做出定时、定点、定量的气象要素精细化气候预报,并参照气象部门制定的相关评分标准,对预报效果进行检验.[结果]目前,广州市精细化气候预测系统常用于制作该市10个站点的6个气象要素(平均气温、最高气温、最低气温、雨量、平均气压、日照)的逐日、侯、旬、月、季、年的气候预测.对近5年(2006~2010年)广州市10个站点的气象要素预报效果进行了检验,预报检验平均得分为:月雨量75.0分,月平均气温94.5分,月最高气温98.6分,月最低气温88.9分;旬雨量77.1分,旬平均气温90.6分,旬最高气温90.1分,旬最低气温82.8分,均达到广东省气象台的目标管理要求.[结论]该系统可广泛应用于农业气侯灾害预报以及大型水库、新机场、核电站等定点预报.  相似文献   

3.
[目的]研究辽西朝阳农村的气温和热量资源变化特征.[方法]选取1966~2010年辽西朝阳农村气象站资料,应用序列相关和气候倾向率等统计方法,对朝阳农村的气温和热量资源变化特征进行分析,掌握该农村的气候现状.[结果]1966~2010年辽西朝阳农村日平均气温、日最高气温和日最低气温的年均值呈波动变化,其中日最高气温年均值趋势升高增温幅度最大(0.328℃/10a),且显著水平最高,是气温升高的主体;日平均气温增幅(0.151℃/10a)和显著水平次之;日最低气温呈下降趋势,且显著水平不明显.在冬、夏半年时间尺度里,日最高气温平均值趋势升高明显,气候倾向率分别为0.417和0.250℃/10a,以冬半年升高最突出;日平均气温趋势性显著水平较低,日平均最低气温趋势性不显著.辽西朝阳农村≥10℃积温呈波动增加趋势明显,气候倾向率为42.590(℃·d)/10a,近45年趋势增加192(℃·d).[结论]该研究为调整农业结构和品种布局等农业措施提供气候依据.  相似文献   

4.
[目的]研究气象因素对杨干象发生的影响.[方法]利用多元线性回归和判别分析的方法分析了1~12月份月极低温度、月极高温度、月平均温度、月降水量等对杨干象发生的影响.[结果]多元线性回归后,建立了回归模型:y=0.781+0.021x<,16>+0.004x<,26>+0.058x<,20>+0.015x<,23>+0.055x<,34>,模型的预测精度达到了利用模型进行预测的基本要求.通过对进入多元线性回归模型中的自变量和因变量的关系进行判别分析,进一步确定了影响杨干象虫口密度的重要气象因子,分别为4月极低温度(x<,34>)、2月极高温度(x<,23>)、1月平均温度(x<,16>)、3月平均温度(x<,26>)和1月降水量(x<,20>).[结论]4月极低温度(x<,34>)、2月极高温度(x<,23>)、1月平均温度(x<,16>)、3月平均温度(x<,26>)和1月降水量(x<,20>)是影响杨干象发生的重要气象因子.  相似文献   

5.
[目的]分析河西走廊东部近50年高、低温气候特征.[方法]利用河西走廊东部5个气象站 1960~2009 年高(日最高气温≥35℃)、低温(日最低气温≤-20℃)资料,运用统计学方法详细分析了高、低气温的时空分布、强度、持续性和环流形势等气候特征.[结果]河西走廊东部高温天气主要发生在东北部沙漠边缘;低温天气主要发生在海拔较高的山区和北部沙漠边缘.随着气候变暖,高温日数呈弱增加趋势,强度增强;低温日数呈明显减少趋势,强度减弱.高温天气主要出现在7、8月;低温主要出现在1、2、12月.高、低温天气具有持续性特征,强高、低温大多出现在高、低温持续时段内.高温天气出现在副热带高压控制及影响的区域内;低温天气出现在强冷空气堆积和入侵的区域内.[结论]该研究为高、低温的准确预报和预警提供了一定的理论基础.  相似文献   

6.
[目的]研究不同植物根系对土壤抗冲性的影响.[方法]采用改进的原状土冲刷水槽法,探讨了不同雨量、不同坡度下,4种植物的土壤抗冲性与根系生物量的关系.[结果]在小雨冲刷下,不同植物上层土壤的抗冲性和根系生物量随着坡度的增大而增强,而下层土壤表现出相反趋势;中雨冲刷下,丁香对上层土壤抗冲性的影响较大,而丁香、红瑞木下层土壤的抗冲性和根系生物量随着坡度的增加而减小;大雨冲刷下,不同植物上层土壤的抗冲性基本上随着坡度的增大逐渐增强,而根系生物量呈相反趋势,在下层土壤中其表现规律不一致.另外,土壤抗冲性与根系生物量密切相关,中雨、大雨冲刷下土壤抗冲指数与根系生物量的相关性明显高于小雨冲刷下.[结论]不同植物根系对土壤抗冲性有明显影响,可为水土流失区的植被修复提供科学依据.  相似文献   

7.
[目的]观察东方蝾螈胃和小肠的组织结构.[方法]制作组织切片,利用显微镜观察组织结构.[结果]东方蝾螈的胃壁和小肠壁由内向外依次可分为黏膜层、黏膜下层、肌层、浆膜层4层,小肠黏膜下层不明显.黏膜层向腔内形成纵褶,且较厚,肌层主要由内环外纵2层平滑肌构成.小肠绒毛由黏膜上皮和固有膜向肠腔突出形成,在十二指肠段密集且较高,向远端(回肠端)渐疏渐短.[结论]东方蝾螈胃和小肠的形态结构较简单,胃肠壁较薄,肌层欠发达.  相似文献   

8.
[目的]分析近49年辽宁省玉米生长季气候变化特征及其对产量的影响.[方法]利用线性趋势模拟、滑动平均等方法,将标准化后的1961~2009年辽阳市玉米播种期、营养生长期及生殖生长期气温、降水、日照等气象资料和玉米单产资料进行对比分析.[结果]近49年玉米生长季各个时期平均气温均呈上升趋势,营养生长和生殖生长期增温明显;降水在播种期变化不大,在营养生长和生殖生长期呈减少趋势;日照在整个生长季均呈减少趋势.无论在哪个生长时期,气温的升高对玉米产量的增加都起到了一定的促进作用;降水和日照的减少是造成近4年玉米小幅减产或增产缓慢的原因.[结论]该研究为政府和农业部门领导科学安排指挥农业生产,充分利用温、光、水资源及准确预报玉米产量提供参考依据.  相似文献   

9.
热轧高强钢回火炉的设计温度范围很大(150~750℃),因此预测钢板在炉内的温度变化对热处理过程非常重要。开发了大型回火炉内的钢板温度预报模型,能够预报不同厚度钢板回火时的温度变化。预报精度与实测值相比在5 K以内,完全满足现场要求。阐述和分析了不同的炉温设置策略,探索其对应的节能效果,找出钢板的优化升温曲线及最佳炉温设定策略,从而实现钢板回火质量达标及炉子能耗最小。  相似文献   

10.
通过对某198 m~2烧结机料层温度以及烧结矿分区质量的测试研究了烧结矿的成矿特性。烧结料层温度测试结果表明:上层烧结矿燃烧带持续时间短、最高温度低,其燃烧带的热流强度(CTI)仅不足下层的10%,说明烧结料层下层热量充沛、液相充足,上层热量不足、不利于液相生成。烧结矿质量分区检测结果表明:烧结矿质量偏析主要集中在垂直方向上,表现为表层烧结矿强度低、抗摔性能和粒度组成差;下层烧结矿强度高、抗摔性能和粒度组成好;30%以上的烧结返矿集中在占总烧结矿料层厚度16.7%的表层烧结矿。基于此,增加表层矿热量、提高表层烧结矿质量是改善烧结矿质量的重要方向之一,热风烧结和厚料层烧结等技术是可行的技术手段。另外,进一步改善偏析布料效果仍需要深入研究。  相似文献   

11.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。  相似文献   

12.
Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.  相似文献   

14.
鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".  相似文献   

15.
张兴强  叶运福 《冶金设备》2005,(6):71-72,47
针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。  相似文献   

16.
17.
通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。  相似文献   

18.
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.  相似文献   

19.
20.
In this paper is treated the fundamental problematic of the fracture of the diaphysis of the tibia and the therapeutic results after the conservative and operative treatment are confronted. Among 518 patients with 433 open fractures and 35 with closed fractures of the diaphysis of the tibia, successful treatment of more 2/3 was obtained in the period from 1968 to 1972. Following our casuistics and literature, whose results are similar, we find out that the average total treatment of the osteosynthesis of the fracture of the diaphysis was shortened for 2,5 months depending upon the type and the localisation of the fracture. Apolied methods of the operative and conservative and conservative treatment in relation to the velocity of the medical cure as well as to the extreme anatomical-functional results are analised. We noticed that osteosynthesis, made by the intermedullary nail and the extension of the canals or by a small AO table, by the achieved stability makes conditions of immediate motions and an early rehabilitation. Because of that it gives the best functional results.  相似文献   

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