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1.
关志强 《广东海洋大学学报》1997,17(2):41-44
通过模拟计算压力比，单位容积制冷量和理论循环制冷系数等性能指标，对比评价ＨＣＦＣ－１２３和ＣＦＣ－１１两种制冷工质，理论分析表明：ＨＣＦＣ－１２３工质性质接近于ＣＦＣ－１１，是当前可以接受的ＣＦＣ－１１的过渡性替工工质。 相似文献
2.
关志强 《广东海洋大学学报》1995,(2)
运用Ａ．Ｃ．Ｃｌｅｌａｎｄ提供的制冷工质热力学参数曲线拟合方程编写程序，对新制冷工质ＨＦＣ１３４ａ应用于理论回热循环的性能指标进行模拟计算和特性评价，并与ＣＦＣ１２回热循环性能指标进行比较。结果表明：在实用的工况范围内，与制冷基本循环相比，以ＨＦＣ１３４ａ为工质采用回热循环可提高循环的理论制冷系数和单位容积制冷量；与ＣＦＣ１２对比，ＨＦＣ１３４ａ回热循环的理论制冷系数较ＣＦＣ１２回热循环的理论制冷系数为低，在蒸发温度较高的工况下，ＨＦＣ１３４ａ回热循环单位容积制冷量大于ＣＦＣ１２回热循环单位容积制冷量，在蒸发温度较低的工况下，ＨＦＣ１３４ａ回热循环单位容积制冷量小于ＣＦＣ１２回热循环单位容积制冷量。 相似文献
3.
根据国外最新实验资料，经过理论分析和计算机绘图，给出了R134a的制冷及热泵理想朗肯循环性能计算的公式及结果，以及压力比、单位制冷量及热力性能系数对蒸发温度和冷凝温度的关系曲线图，并对其进行了分析。可供设计和研究采用这种工质的制冷设备和热泵时参考。 相似文献
4.
根据国外最新实验资料，经过理论分析和计算机绘图，给出了Ｒ１３４ａ的制冷及热泵理想朗肯循环性能计算的公式及结果，以及压力比，单位制冷量及热力系数对蒸发温度和冷凝温度的关系曲线图，并对其进行了分析。可供设计和研究采用这种工质的制冷设备和热泵时参数。 相似文献
5.
以氨一次节流中间完全冷却两级压缩制冷循环为例．模拟计算两级压缩制冷循环制冷系数和压缩机单位容积制冷量随工况和高低压容积比变化的情况，得出一系列结论，为探讨合理的两级压缩机高低压容积比和确定最佳运行工况提供指导。 相似文献
6.
济宁市保有煤炭资源储量123．9亿t，其中天然焦4．1亿t，约占山东省的一半。随着几大天然焦赋存煤田周边勘探找煤工作的深入，天然焦的资源储量还将增加4亿～11亿t，最终济宁市的天然焦资源储量将达8亿～15亿t。如何综合利用天然焦将直接影响济宁市乃至山东省资源开发利用水平，并关系到“节能降耗”的能源战略和矿区的服务年限。 相似文献
7.
关志强 《广东海洋大学学报》1994,(2)
采用非线性二乘法对国产１２．５系列往复活塞式制冷压缩机的实测性能数据进行拟合，得出描述该系列制冷压缩机性能系数与运行工况之间相关关系的曲面回归方程，为制冷系统的数值计算、动态特性模拟和优化设计提供数学模型。 相似文献
8.
积－微分方程是一类应用广泛且讨论较难的数学问题，其中，反问题更具有实际应用价值。本文研究了一类以迁移理论为背景的积－微分方程的反问题，证明了这类反问题解的存在性和唯一性。 相似文献
9.
热泵是消耗一定高品位能源把能量从低温物体传递到高温物体的设备。热泵是以低温地热水作为热泵夏季制冷的冷却源、冬季采暖供热的低温热源，同时是实现采暖制冷和生活用热水的一种系统。它用来替代传统的用制冷机和锅炉进行空调采暖和供热的模式，是改善城市大气环境和节约能源的一种有效途径，也是国内地源能利用的一个新发展方向。 相似文献
10.
残余和现今应力场重迭法预测强震危险时区 总被引：3，自引：0，他引：3
以红河断裂带测区为例，用Ｘ射线法测量了测区的古构造残余应力场及其应变能密度场，用有限单元法计算了测区在两种边界条件下的水平最大剪应力场，用实验和理论证明了古构造残余主压应力大小和方向对岩石破坏、破裂扩展和震级的影响。用上述方法预测，松平—南涧、玉溪—开远、普洱为测区内强震危险区段。结合地球自转角速度相对变率的天文观测曲线在时间轴上的外延，预测得１９８９－１９９６、１９９９－２００４、２００７－２０１３、２０１６－２０１８年为测区内强震危险时段。 相似文献
11.
韩丽君 《中国海洋湖沼学报》2003,21(2):171-179
Measurements of three chlorofluorocarbons(CFCs) :trichlorofluoromethane (CFC-11),dichlorodifluoromethane (CFC-12) and trichlorotrifluoroethane (CFC-113), along with methyl chloroform (CH3CCl3) and carbon tetrachloride (CCl4) were made in water samples from Lake Washington,using Electron Capture-Gas Chromatography (EC-GC).The samples were collected in mid-autumn, a period when the lake‘‘‘‘‘‘‘‘s upper layer undergoes rapid cooling,At the time of sam-pling,a strong vertical temperature gradient was present in the lake,with surface temperatures of -14℃,and near bottom(50 meters) temperatures of -8℃ ,The concentrations of dissolved CFC-12 and CFC-11 increased with depht ,as expected from the higher solubilities of these gases at lower temperatures ,Atmospheric measurements made at the sampling site at the time of the cruise ,showed that CFC-11 and CFC-12 saturations in the near surface samples were 100% and 106%,respectively,For the deepest sample (52 meters)CFC-11 and CFC-12 saturations were 102% and 126%,Because the surface layer of the lake respondes to changes in atmospheric CFCs on a time scale of several weeks ,the highere than equilibrium concentrations of CFC-12 observed at the time of sampling may reflect earlier episodes of elevated levels of atmospheric CFC-12 in this urban area.High concentrations of dissolved CFCs in runoff or industrial effluent might also lead to elevated CFC levels in the lake. The cold ,deep water of Lake Wahington is realtively isolated from the effects of surface gas exchange except during winter ,and the supersaturations observed in the deep layer may reflect pe-riods of elevated atmospheric CFC-12 levels from the previous winter season.These results were compared to summertime profiles of CFC-11 and CFC-12 made in 1994. 相似文献
12.
In this paper, we characterize the North Yellow Sea (NYS) water masses in summer by analyzing temperature and salinity data
surveyed in 2006. The Liaonan Coastal Water is characterized by low salinity westward and southward flow paths. The westward
path flows parallel to land, turns to the south, then to the southeast adjacent to the mouth of the Lüshun River, where it
mixes with other coastal water directly to the southwest. It becomes the main source of low salinity water in the deep water
area west of 123°E. The high-salinity Lubei Coastal Water is the remnant of the winter Lubei Coastal Water, which is located
mostly in a small area between Yantai and Weihai, and does not originate in the Bohai Sea Coastal Water. The two NYS zones
demarcated at 123°E have distinctly different temperature and salinity characteristics. There are two high-salinity centers
east of 123°E, whereas there is low-salinity water to the west whose temperature and salinity structures are complex, composed
of the coastal water south of Chengshantou, the Liaonan Coastal Water and the Bohai Sea Water. 相似文献
13.
采用罗丹明123(Rh123)和碘化丙啶(PI)两种荧光染料对栉江珧(Atrina pectinata)精子线粒体活性进行检测,比较不同染液浓度和染色时间的检测效果,并用该方法检测和比较超低温冷冻保存对线粒体活性的影响。结果显示:Rh123和PI染色的最适染液浓度均为10μg/mL,染色时间控制在10 min之内;染色后具有线粒体活性的精子发出绿色荧光,死精子发出红色荧光,质膜受损但线粒体还未受损的精子发出红绿色荧光,表明Rh123和PI双荧光染色检测栉江珧精子线粒体活性是可行的;精液经冷冻后,线粒体活性为61.9%、质膜完整率56.8%,显著低于新鲜精液组(95.3%、93.5%),表明冷冻对精子结构会造成不同程度的损伤,Rh123和PI双荧光染色法可用来检测栉江珧精子质量。 相似文献
14.
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????????YRY??2????????????????????о????????????????????????????????????????????????????????????????????????????2004??12??26???2005??3??28???????????????δ???????????????????????????0T11??0T18????????????ε????????仯??????????????ε???????0T11??0T18???????????????????????仯???С????????????????????????????????????????????2???????????????????????????????ù???????? 相似文献
15.
??????GPS?????????????????????????????????11??PVA??Position??Velocity??Acceleration)?????????е?????λ??????????????????????????????????????????????????????????????????????ó???????????????????????·??Ч?????????????????????λ???????????????????????????? 相似文献
16.
Based on survey data from April to May 2009, distribution and its influential factors of dissolved inorganic nitrogen (DIN) over the continental slopes of the Yellow Sea (YS) and East China Sea (ECS) are discussed. Influenced by the Changjiang (Yangtze) River water, alongshore currents, and the Kuroshio current off the coast, DIN concentrations were higher in the Changjiang River estuary, but lower (<1 μmol/L) in the northern and eastern YS and outer continental shelf area of the ECS. In the YS, the thermocline formed in spring, and a cold-water mass with higher DIN concentration (about 11 μmol/L) formed in benthonic water around 123.2°E. In Changjiang estuary (around 123°E, 32°N), DIN concentration was higher in the 10 m layer; however, the bottom DIN concentration was lower, possibly influenced by mixing of the Taiwan Warm Current and offshore currents. 相似文献
17.
一种短基线硐体应变仪 总被引：1，自引：0，他引：1
实验发现,在硐体完整基岩1 m深处,日温度波动只有硐体空气中日温度波动的的百分之一左右.将1m基线的硐体应变仪,用自应力水泥耦合在硐体1 m深度的基岩槽中,可以提高硐体应变仪的稳定性和高频性能. 相似文献
18.
精密和详细测定地球重力场及其时间变化，是目前卫星重力测量的主要课题。基于固体潮研究的最新成果，研究了固体潮对地球重力场时变特征的影响。不同于IERS2003采用的Cartwright和Tayler(1971)的引潮力位(TGP)展开，而是利用郗钦文的TGP展开，给出了固体潮对地球重力场时变特征影响的理论公式，并考虑到4阶潮汐的效应，精度可达到1011^-11ms^-2量级，同时采用最新的TGP展开数据重新计算了固体潮Love数相对频率特性对地球引力场的影响，并考虑了较多的潮波项，最后对重力数据归算中的永久性潮汐的处理进行了总结和说明。 相似文献
19.
Light transmission data collected from June to July 1987 and from February to March 1997 by the R/V Kexue 1 in the East China Sea were used to analyze its distribution characteristics and its relation to the sediment transport in this sea. Some results obtained were: (1) The Taiwan Warm Current flowing northwards seemed to be a barrier preventing suspended matter discharged from the Changjiang River Estuary from continuously moving southeastward and causing the suspended matter to flow along a path near 123°30′E in summer and 123°00′E in winter. (2) Suspended matter in the area adjacent to the Changjiang River Estuary could not be transported southward along the coast in summer due to opposing offshore currents including the Taiwan Warm Current flowing northward and the Changjiang Diluted Water turning northeastward. (3) The thermocline and temperature front bar suspended matter from crossing through. 相似文献
20.
成都市空气质量预报中WRF的本地化参数选取 总被引：1，自引：0，他引：1
为更准确的研究气象因素对成都市空气质量的影响,需要进一步提高天气预报模式WRF的模拟效果。设定16种天气预报模式WRF中尺度数值模式的参数化方案与气象信息综合分析处理系统(MICAPs)的气象实测数据进行地表温度(T2m)和海平面气压(Psl)及高空温度的比对,通过统计学方法进行结果评估,选取适用于成都市本地化的天气预报模式WRF参数方案。结果表明:第15组参数化方案模拟结果与气象信息综合分析处理系统(MICAPs)气象实测数据的对比分析效果表现最佳,是为成都市空气质量预报中天气预报模式WRF的最优参数设置,第11组次之。 相似文献