半导体制冷果蔬配送箱水冷散热参数优化试验研究

为提高半导体制冷果蔬配送箱的工作性能,提高半导体制冷片热端散热效率,降低散热系统能耗与质量,搭建水冷半导体果蔬配送制冷箱试验平台,针对水泵流量、散热风机风速、水箱容量对半导体制冷性能的影响进行试验研究。结果表明,导体制冷果蔬配送箱最佳水冷散热参数为:水泵流量为13 cm~3/s,散热风机风速4 m/s,水箱200 m L;在该参数条件下,箱内空气温度从25℃降到7℃仅需580 s,半导体制冷片能耗25 165.20 J,制冷系统总能耗为28 408.10 J,制冷效率26.004%,保证了较快的制冷速度和较小的水箱体积,并减少降温能耗。研究结果为便携式果蔬配送系统的设计和优化提供理论依据。     

太阳能制冷低温储粮应用效果初探

从降低机械压缩式制冷低温储粮能耗及运行成本的角度出发,设计、建造了一台太阳能吸附式制冷系统,并将该系统在高温季节进行了低温储粮的实仓实验。测试结果表明:在夏秋高温季节,采用太阳能制冷系统冷却粮仓上部空气隔离层,可有效降低仓温,抑制粮温回升,实现准低温储粮。经济性分析表明太阳能制冷系统用于低温储粮的运行成本明显低于压缩式制冷谷物冷却机。     

太阳能制冷空气隔离层环流通风储粮试验研究

低温储粮是一种具有广阔应用前景及实用价值的科学储粮方法。将太阳能制冷应用于低温储粮能有效节约常规能源。本文根据太阳能制冷系统的特点及仓内粮温分布规律,提出了采用太阳能制冷系统进行仓内空气隔离层(仓内粮堆上部空间)环流通风的储粮技术,并在中央储备粮扬州直属库进行了试验。结果表明:采用仓内空气隔离层环流通风冷却方式可有效地抑制高温季节仓内上层粮温的升高。在仓内上层平均粮温回升到15~20℃前将太阳能制冷系统适时地投入运行,能够实现准低温储粮。     

纯电动车车用复合储能装置控制策略及参数优化

为解决目前纯电动车动力电池比功率不足的缺陷,对纯电动车的储能装置进行了研究。根据复合储能装置的特点和目的,制定了复合储能装置的工作模式,提出了基于速度与电流约束的模糊控制策略。为了进一步提高整车性能并降低蓄电池的输出电流,对复合储能装置的关键参数进行了线性优化,仿真结果表明:加装复合储能装置的纯电动车的加速时间缩短了12%,制动能量回收效率提高了39%,百公里耗电量减少了8.55%,并显著降低了蓄电池的输出电流,有效延长了蓄电池使用寿命和整车的续驶里程。     

基于Zigbee无线冷藏车厢信息采集节点设计

摘 要：针对食品冷链全过程中运输环节实时监测的需要,利用无线传感器网络布线容易、成本低、低功耗等特点设计出能有效的实现物流配送中环境信息的在线采集与实时监测的Zigbee无线冷藏车厢信息采集节点。该节点使用以Jennic公司生产的Zigbee无线微型控制器JN5139-Z01-M02R1模块为核心,英国SENSIRION公司的SHT75为传感器,在实际应用中测试,证明该系统可行,可靠。     

太阳能制冷机组通风系统中粮库温度的系统分析

针对不同的粮库内部太阳能制冷机组空调分布形式,利用CFD计算软件,采用标准k-e模型对粮库内部的大空间气流组织的非稳定特性进行三维数值模拟,分别比较了集中辐射式分布和沿四壁周向式分布两种形式的粮食表面附近的截平面的速度和温度分布,模拟结果显示:采用集中辐射式分布的模型流场扰动范围大,换热效果好,温度场分布均匀,整体降温效果好.由此可以看出流体计算技术在研究空调换热空间速度场和温度场分布的巨大作用,为空调的设计运行参数提供了重要依据,从而可以选用换热效果更好的空调分布形式.     

神经网络自变量输入模式的视电阻率求解算法

根据瞬变电磁场理论公式中的响应和自变量之间的关系特点,提出用非线性方程模式的BP神经网络求解电阻率。通过构造单输入单输出网络结构,建立以不同时间点上的电流归一化的感应电压值为输入、视电阻率值为输出的神经网络,来拟合瞬变电磁场的二次涡流曲线。利用数值方法计算出的数据验证该训练网络的精确性,比较了不同算法对训练精度和收敛速度产生的影响。以重庆大学某处的防空洞探测实验为例验证了该算法的有效性,该算法避开具体的复杂电磁场计算或数值反问题计算,从而实现电阻率快速计算,为快速成像准备必要条件。     

屋顶花园绿地设计方案部分生态效益预测分析

以深圳市创富时代·俊景园景观规划的屋顶花园方案Ⅱ自然式设计为研究对象,借助CITYgreen 5.0软件,对该方案绿地建设当年以及二十年后在减少大气污染以及碳汇和碳吸收方面能够产生的部分生态效益进行了数量化、货币化分析,并对该设计方案的合理性进行快速评价,再根据分析结果提出相应的屋顶花园绿化与管理建议。结果表明,研究范围的绿地2007年在清除大气污染物以及碳汇和碳吸收方面的生态效益总价值为8 537.09元人民币。随着植物的生长发育,其可能产生的效益将会有所增加。     

植株叶绿素a和叶绿素b无损检测系统研究与开发

针对透射式叶绿素检测技术在检测较高含量叶绿素叶片时的局限性,研究设计基于光学漫反射式新颖的叶绿素检测系统,实现无损在线测试,直接输出植株叶片叶绿素a和b值。该检测系统采用3光源3光束垂直入射密闭光路设计,选用645 nm和663 nm 2个特征波长作为叶绿素a和b的检测波长,800 nm作为参照波长;采用光源调制、高通滤波放大和软件算法等消除外界光干扰;以透光度75%的消光片对该检测系统进行稳定性和重复性测试评价。测评结果为稳定性RSD≤0.39%(n=20),重复性RSD≤0.59%(n=20)。选取小麦、玉米、花卉共344个样本,漫反射法和常规Arnon法的叶绿素a和b总量的相关性达到极显著水平;且适用于厚度约3.0 mm玻璃翠花叶片的检测。     

基于变异系数法建立蒲公英脆片不同因素与评价指标的选择

为使蔬果的食用不受季节限制且符合当下绿色健康的食品理念,蔬菜脆片应运而生,但不同蔬菜脆片的研制过程中所用的指标不尽相同。为了给蔬菜脆片研究与相关食品开发提供更科学、精准的评价指标,以蒲公英脆片研制为例,对蒲公英脆片生产工艺中膨化时间、膨化功率、马铃薯淀粉用量与物料厚度等因素对脆片品质影响进行研究。首先,利用变异系数法分析脆片的膨化率、硬度、脆度、模糊数学法感官评分等指标在脆片品质评价所占的权重。结果表明,对蒲公英山野菜脆片品质影响从大到小的指标依次为脆度>模糊数学感官评分>硬度>膨化率;再经过标准化并结合权重进行计算,得到对蒲公英脆片品质影响从大到小的因素依次为膨化时间>膨化功率>脆片厚度>马铃薯淀粉用量。     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.