土壤硝态氮含量测定方法的选择和验证

对经典的酚二碳酸法和Ｎｏｒｍａｎ等人提出的紫外分光光度法测定土壤浸提液中硝态氮含量的可行性进行了对比验证。结果表明,用紫外分光光度“差减法”测定土壤侵提液中的硝态氮含量,在精度上能满足测定之需要（与酚二碳酸法相比）;由于供试土壤系列在２７０ｎｍ处的吸光度极低,因而,用Ｒ值校正和不校正结果间的差异不明显;对给定的土壤系列而言,土壤样品在２１０ｎｍ处的吸光率受土壤中其他非硝酸根离子含量的影响不大,因此“直接法”和双波长法的测定结果之间差异可忽略不计;在６０℃条件下鼓风烘干３～４小时,结果与湿士测定间的差异不明显,完全能满足农化服务大批量分析测定之需要。     

棉花种子水分测定前处理方法的研究

本试验选用高、中、低三种水分棉花种子、五种处理方法,进行棉花种子含水量的测定。结果表明:“对切法”与国家标准《农作物种子检验规程》的“切片法”相比,在高、中含水量情况下测值差异不显著,且提高工效6倍以上;整粒、夹玻、粉碎等处理测定结果与“切片法”相比,差异达极显著,测值偏低。“对切法”准确、快速、简便,是测定棉花种子水分较好的方法,在当前科研、生产中具有实用价值。     

Fluorescence decay times: proteins, coenzymes, and other compounds in water

The fluorescence decay time (tau) was 2 to 5 nanoseconds for proteins and 4 to 5 nanoseconds for flavin, pyridine nucleotide, and vitamin B(6)coenzymes; tau varied widely in 48 compounds measured in water. Altholugh reported values of tau for a few of the soluttions studied were in excellenlt agreement. previously "calculated" lifetimes, in severall instances, are apparently erroneous. Nonexponential decay was detectable with our "nanosecond-flash" apparatus, a modification of the first commercially aavilable unit for determination of tau.     

烟草根系柠檬酸分泌特性的遗传规律分析

[目的]改善烟草根系对土壤钾的活化能力,提高对钾的吸收效率。[方法]以农大202、中烟101、NC628、K358、NX232共5个烟草品种为亲本,采用双列杂交试验研究了烟草根系柠檬酸分泌特性的遗传规律。[结果]不同品种间烟草根系柠檬酸分泌特性存在显著差异。在柠檬酸分泌特性上,农大202的一般配合力效应值和农大202×NC628特殊配合力效应值均为正,对改善后代钾吸收效率有较高的利用价值。烟草根系柠檬分泌酸特性的遗传规律符合"加性-显性"遗传模型。缺钾敏感性不符合"加性-显性"遗传模型。[结论]该研究为进一步研究烟草根系柠檬酸分泌特性奠定了理论基础。     

Effects of Root-Zone Temperature on Growth,Chlorophyll Fluorescence Characteristics and Chlorophyll Content of Greenhouse Pepper Plants Grown under Cold Stress in Southern China

In Southern China, plants are usually exposed to cold stress during winter in an unheated greenhouse, but due to the high energy consumption and costs, most of the greenhouses remain unheated. In an attempt to find a simple and affordable solution to this problem, this study was undertaken. In this research, Capsicum frutescens L. plants were studied to investigate the effect of different root zone temperatures on its growth and chlorophyll fluorescence characteristics under cold stress. The plants were cultivated under cold stress conditions in a root zone temperature (RZT) control system where the roots were subjected to four different root-zone temperature treatments of 20°C-T20, 25°C-T25, 45°C-T45 and a control CK group. Growth characteristics studied included plant height, stem diameter, plant width, root length, biomass accumulation. Whilst fluorescence characteristics investigated were chlorophyll fluorescence ratio F_v/F_m, photochemical quenching (qL), efficiency of Photosystem II (Y[II]) and electron transport rate (ETR). Chlorophyll content in the leaves of the plants was also investigated. The findings demonstrated that plants in the CK group suffered a detrimental effect on the growth characteristics registering the lowest values in the measured variables. Conversely, the highest values were observed in T25 RZT treatment. In fluorescence characteristics, values of F_v/F_m were maintained at between 0.8 and 0.83 but also suffered a photo-inhibitory depression in CK and T45 RZT treatments to F_v/F_m values of <0.79. This depicted that root zone heating protected the PS II of these plants from photoinactivation induced by cold stress. Similar trends were seen in the qL, Y[II], ETR values with the T20 and T25 treatments registering the highest values. Chlorophyll content was significantly higher in the leaves of the plants in the T20 and T25 group. The lowest chlorophyll content was recorded in the CK group. Plants in all the treatments accumulated more biomass in the shoot than in the roots as depicted by a significantly lower shoot to root ratio values with the exception of those in the CK group. The findings of this study suggest that pepper plants can successfully be grown in an unheated greenhouse in the Yangtze River Delta area of Southern China during winter by heating the root zone of the plants to a RZT value of 25°C, thereby providing a simple, affordable and cost-effective technique.     

紫花含笑新品种的选育

从紫花含笑中选育出新品种墨紫含笑。经无性繁殖和多年观测,该品种花大,颜色为墨紫色,芳香,花瓣具有明显银白色镶边,花期长达3个月,抗性和适应性强,具有较高的园林观赏价值。     

简析张仲景医学伦理思想

医圣张仲景医德高尚,有着丰富的医学伦理思想。张仲景对于患者能持守“医道”原则：创六经之道救治患者;重视与患者疾病相关的一切因素;结合体质辨证;弘扬医家人文关怀。张仲景对于医学同行创“辨证”诊疗并无私传道：规范“辨证论治”,反对轻率诊疗;“考校以求验”,反对轻信医书;简明无私传道,反对藏私捂道。张仲景对于一般社会民众相和于“治未病”。这些思想具有一定现世价值。     

播期和种植密度对水稻“中浙优1号”RVA特征值和米饭质地的影响

以水稻组合"中浙优1号"为材料,研究播期和种植密度对其常规品质、RVA特征值和米饭质地的影响。结果表明,不同播期和密度处理下,供试样品的整精米率、垩白度、直链淀粉、RVA的消减值和回复值以及米饭硬度共6项指标差异达显著水平。不同播期试验中,播期Ⅲ(6/15)稻米的整精米率最高;播期Ⅰ(6/5)、Ⅱ(6/10)样品的淀粉RVA特征曲线接近,且其峰值粘度明显高于后3个播期;后3个播期淀粉RVA特征谱接近;播期Ⅰ、Ⅱ米饭粘性较高,且播期Ⅱ的硬度最小。不同种植密度处理试验中,种植密度Ⅱ(13.5万丛/hm2)处理的整精米率最低,种植密度Ⅴ(27万丛/hm2)的整精米率最高,两者差异达6.1%;种植密度Ⅴ处理的RVA的消减值、回复值和米饭质地的硬度均为最小。"中浙优1号"在温州地区可于6月10日左右播种,并选择27万丛/hm2的种植密度,其RVA的消减值约-50 RVU,米饭硬度约0.5 kg,粘性约20.0 g.mm2,米饭食味品质较好且米饭冷后不易回生。     

Is value conflict inherent in rural economic development? An exploratory examination of unrecognized choices

Rural development and economic change has generally been associated with growth and the in-migration of nonlocal firms or their branch plants and offices. Such change has been critiqued and at times resisted because of its implicit urbanism and conflict with rural values and modes of social interaction. The inevitability of the conflict has always been assumed, given the perspectives of development groups and many rural residents. This paper examines the apparent conflicts between the rural ethos and the growth ethos, and the considers the necessity for the pursuit of the forms of growth that tend to undermine rural values. The severely limited set of changes in the local economy considered by the common forms of growth-sponsoring economic development groups is then examined. Finally, the existence of alternative forms of economic change are hypothesized and their viability demonstrated. We conclude that improved economic well-being for rural residents need not sacrifice their values and lifestyles on the altar of urban-influenced economic growth.Peter B. Meyer is professor of Urban Policy at the University of Louisville. He was previously employed at The Pennsylvania State University where he directed the Local Economic Development Assistance Project, a research/technical assistance service to smaller cities, towns, and rural counties. Dr. Meyer's research interests are in processes of community and economic development in capitalist and third world countries and the ways in which processes and their outcomes are measured and valued.     

Total luminous flux: a possible response determinant for the normal monkey

Thirteen normal monkeys (Macaca mulatta) trained to discriminate between transilluminated figures of equal area and different luminance, and consequently different luminous flux, made similar numbers of errors during training on a new problem with the same luminance values but with targets equated for luminous flux. These findings together with results of "critical trials" suggest that the significant cue in the original problem was luminous flux. This behavior is strikingly similar to what has been reported for the monkey following exclusion of the geniculostriate system.     

防治母畜子宫内膜炎新药宫炎清的研制

宫炎清为甲酚磺酸与甲醛的缩合产物.本品采用混合甲酚为原料,经硫酸磺化,然后再与甲醛缩合而成.抗菌试验证明,宫炎清对大肠肝菌、金黄色葡萄球菌、绿脓杆菌、溶血性链球菌、变形杆菌等有较好的抗菌作用。对奶牛急慢性子宫内膜炎有较满意的治疗效果.经分析测定,本品质量稳定;毒副作用较小,小白鼠1次经口内服LD_(50)为698.2mg/kg,以4％宫炎清溶液冲洗母兔子宫,对母兔受孕、活产、仔兔出生成活率及子宫组织无不良影响。     

Differences in EM-38 Readings Taken Above Crop Residues Versus Readings Taken with Instrument-Ground Contact

Soil apparent electrical conductivity (EC) as measured by electromagnetic induction (EM) using the Geonics® EM-38 has shown promise as a soil survey tool in Iowa and other parts of the American Midwest. Surveys made with the EM-38 often take place in the fall after harvest or in the spring prior to planting. Because of this, and because use of conservation tillage and other techniques that leave crop residues on the soil surface is prevalent in many parts of the United States, it is common for fields to have crop residues covering the soil surface when EM surveys are conducted. These residues might alter the soil EC values obtained with the EM-38. To test this possibility, soil EC was determined at two sites with three different types of residue cover (corn (Zea mays L.), soybeans (Glycine max L.), and durum wheat (Triticum turgidum L.)). The residue cover at each site was then brushed aside, and the soil EC was determined with bare ground exposed to the EM-38. On average, soil EC readings were 0.2mS/m higher when the EM-38 was exposed to bare ground, and 68% of the bare ground readings were higher than the corresponding readings through crop residues. However, the 0.2mS/m average difference is not significant when compared to the natural variation found in soil EC readings within any given soil series. Therefore, the results of this study indicate that soil EC values obtained with the EM-38 through crop residues are valid representations of the actual soil EC value.     

气候变化对黑龙江玉米产量贡献份额研究

应用AEZ模型计算得到的1980—2009年逐年光温生产潜力和气候生产潜力作为气候变化影响因素,结合搜集到的1980—2009年黑龙江玉米生产的经济社会要素,本研究构建了主成分分析模型进行气候变化对玉米单产的贡献分析。结果表明:"气候变化及应对措施"主成分影响占到10%略多,"经济社会"主成分贡献率最大,达到50%以上;"传统投入"主成分贡献率约17%;相比较"经济社会"和"传统投入"主成分而言,"气候变化及应对措施"贡献份额最低。"气候变化及应对措施"1980—2009年的主成分得分呈现不规则波动,没有明显上升或下降趋势,表明气候的实际作用不明显。同时,该主成分得分与黑龙江玉米产量变化没有相关性;与黑龙江玉米产量呈线性相关的是"经济社会"主成分。     

Religious and sacred imperatives in human conflict

Religion, in promoting outlandish beliefs and costly rituals, increases ingroup trust but also may increase mistrust and conflict with outgroups. Moralizing gods emerged over the last few millennia, enabling large-scale cooperation, and sociopolitical conquest even without war. Whether for cooperation or conflict, sacred values, like devotion to God or a collective cause, signal group identity and operate as moral imperatives that inspire nonrational exertions independent of likely outcomes. In conflict situations, otherwise mundane sociopolitical preferences may become sacred values, acquiring immunity to material incentives. Sacred values sustain intractable conflicts that defy "business-like" negotiation, but also provide surprising opportunities for resolution.     

Metrology and the state: science, revenue, and commerce

"Natural measures of quantity, such as fathoms, cubits, inches, taken from the proportion of the human body, were once in use with every nation," taught Adam Smith in his lecture "Money as the measure of value and medium of exchange," delivered in 1763. "But by a little observation," he continued, "they found that one man's arm was longer or shorter than another's, and that one was not to be compared with the other; and therefore wise men who attended to these things would endeavour to fix upon some more accurate measure, that equal quantities might be of equal values. Their method became absolutely necessary when people came to deal in many commodities, and in great quantities of them." Smith's comments and the rationale underpinning them became increasingly urgent toward the end of the eighteenth century.     

“捆绑式”申报世界文化遗产模式研究——以新疆坎儿井与交河故城世界遗产资源和文化价值分析为例

通过提出"捆绑式申遗"概念,并结合新增"捆绑式"世界文化遗产现状,对新疆坎儿井与交河故城世界遗产资源和文化价值及其"捆绑"情况进行了详实地分析。     

壳聚糖处理对"杨小-2,6"南丰蜜桔果实采后生理及贮藏效果的影响

采用3种不同浓度的壳聚糖处理,研究它们在冷藏(5±1)℃条件下对杨小-2,6南丰蜜桔果实采后生理生化及贮藏效果的影响。结果表明:壳聚糖处理显著抑制了果实腐烂和失重,减缓了可溶性固形物含量的上升速度,延缓了糖酸的转化,大大提高了果实中可溶性蛋白质的含量,但对Vc含量影响不大;强烈抑制了果实的呼吸强度;同时,壳聚糖处理还有效地推迟并提高了过氧化氢酶(CAT)活性高峰,延长了货架期。在整个贮藏过程中发现,运用15g/L处理的效果最好。     

不同水氮耦合条件下棉花冠层NDVI分析与产量估算

为研究冠层归一化差值植被指数(Normalized difference vegetation index,NDVI)在棉花重要生育时期估算棉花产量的可行性,使用GreenSeeker分别对不同灌水施肥条件下棉花光谱反射率NDVI值进行测定优化,建立NDVI值与产量关系数学模型,并对模型精度进行验证。结果显示:不同水氮组合随着生育期的推移棉花冠层NDVI值变化趋势基本一致,都呈"低-高-低"的变化规律;选取在棉花出苗后80、105和140d冠层NDVI值分别与产量进行相关性分析,得出冠层NDVI值与产量具有明显的正相关关系,相关系数分别为R2=0.376 0,0.093 4,0.363 9。利用独立的试验数据对相关性最高的水氮组合棉花出苗后80d的产量模型进行模型验证,其相关系数R2=0.712 6,均方根误差(Root mean square error,RMSE)561.04kg/hm2。因此,棉花出苗后80d的冠层NDVI值可以估测棉花产量。     

转扁桃AcCBF1基因对烟草光合及叶绿素荧光特性的影响

【目的】扁桃AcCBF1基因对光合作用的影响,为扁桃新品种选育提供科学依据。【方法】采用农杆菌介导法获得转AcCBF1基因烟草,在经过连续室外37℃高温天气一周后,以野生烟草为对照,测定和分析试验烟草的光合参数和叶绿素荧光参数日变化特性。【结果】利用农杆菌介导法成功获得3株转基因烟草,经PCR检测证明AcCBF1基因已稳定地整合到烟草基因组中。转基因烟草和野生烟草的Pn、Gs均呈现“双峰”曲线,且峰值出现时间一致。12:00达到第一个峰值,16:00出现光合“午休”,18:00达到第二个峰值。二者的Pn日均值分别为6.496 、4.553 μmol/(m²·s);Gs日均值分别为157.357 、133.371 μmol/(m²·s)。转基因烟草和野生烟草的Fo均呈现出先上升后下降的趋势,Fm呈现先下降后上升的趋势。Fv/Fm、Fv/Fo、ΦPSII与Fm日变化趋势一致,均呈现先下降后上升的趋势,二者的Fv/Fm日均值分别为0.821、0.736;Fv/Fo日均值分别为5.044、3.391、ΦPSII日均值分别为0.763、0.600。【结论】与野生烟草相比,转AcCBF1基因烟草同化CO₂能力较高,光合能力较强,光合反应中心较稳定,对高温的适应能力较强。扁桃AcCBF1基因能够有效改善烟草的光合作用,维护光合反应中心的稳定;选育扁桃AcCBF1高表达品种应对夏季的干旱高温。     

Ground water redox reactions: an analysis of equilibrium state applied to eh measurements and geochemical modeling

Computer modeling of 611 high-quality analyses of normal ground waters from diverse geographic areas reveals that aqueous oxidation-reduction reactions are generally not at equilibrium. Multiple redox couples present in individual samples yield computed Nernstian Eh (redox potential) values spanning as much as 1000 millivolts. The computed Eh values do not agree with each other, nor do they agree with the single "master" value measured in the field with a platinum electrode. Because of internal disequilibrium, the use of any measured Eh value as input to equilibrium hydrogeochemical computer models will generally yield misleading results for normal ground waters.