中华蜜蜂群体内温度、湿度及CO2浓度的变化及调节研究

采用可以测量肯时温度、相对湿度及ＣＯ２浓度值的电子显示仪,对中华蜜蜂（Ａｐｉｓｃｅｒａｎａ ｃｅｒａｎａ Ｆａｂ．）群体内温度、湿度及ＣＯ２浓度这３种生态因素进行测量,在施加人为干扰条件下,这些因素的变化及恢复过程。以意大利蜜蜂（Ａｐｉｓｍｅｌｌｉｆｅｒａ ｌｕｑｕｓｔｉｃａＬ．）作对照。结果表明：中华蜜蜂维持群体内温度及ＣＯ２浓度稳定性不及意大利蜜蜂,子脾间及箱内空间的相对湿度（ＲＨ）高于意大     

Decadal variation of the surface water PCO2 in the western and central equatorial Pacific

The equatorial Pacific Ocean is one of the most important yet highly variable oceanic source areas for atmospheric carbon dioxide (CO2). Here, we used the partial pressure of CO2 (PCO2), measured in surface waters from 1979 through early 2001, to examine the effect on the equatorial Pacific CO2 chemistry of the Pacific Decadal Oscillation phase shift, which occurred around 1988 to 1992. During the decade before the shift, the surface water PCO2 (corrected for temperature changes and atmospheric CO2 uptake) in the central and western equatorial Pacific decreased at a mean rate of about -20 microatm per decade, whereas after the shift, it increased at about +15 microatm per decade. These changes altered the CO2 sink and source flux of the equatorial Pacific significantly.     

施肥对红壤有机碳矿化特征的影响

为阐明不同肥料施用对红壤有机碳矿化及几种碳形态的影响,对长期定位试验红壤单施有机肥(M)、施用化肥(NPK)、化肥十有机肥(NPKM)、不施肥(CK)4个处理的土样进行室内培养,在培养期间定期采样红壤CO2释放量及土壤微生物生物量碳(SMBC)和可溶性有机碳(WSOC)的含量进行分析.结果表明:1)不同施肥处理CO2释...     

干湿交替条件下铁氧化对水稻土CO_2排放的影响

以湖北省2种典型水稻土[咸宁市的中稻-冬闲水稻土(第四世纪红壤,XR)和潜江市的中稻-冬闲水稻土(钙质潮土,QR)]为材料,研究土壤干湿交替条件下[土壤落干(孔隙含水率55%)到完全淹水(土水比1∶1)]添加Fe2+对土壤Fe3+、可溶性有机碳(DOC)含量及CO2排放的影响,拟揭示水分转变过程中土壤活性铁氧化对土壤有机碳固持的影响。结果表明,整个培养期间,与CK(不添加Fe2+)相比,添加Fe2+促进了XR和QR土壤中活性铁的氧化,XR和QR土壤中Fe3+平均含量分别较CK提高了133.87%和95.66%。落干期间,与CK相比,添加Fe2+促进了CO2的排放,XR和QR土壤CO2累积排放量分别增加了59.77%和124.48%;促进了土壤DOC的积累,XR和QR土壤DOC平均含量分别提高了42.57%和23.71%。淹水期间,与CK相比,添加Fe2+抑制了CO2的排放,XR和QR土壤CO2累积排放量分别降低了54.03%和35.27%;培养前期促进了土壤DOC的积累,培养后期抑制了土壤DOC含量的积累,总体上XR土壤DOC平均含量降低了35.29%,QR土壤DOC含量提高了16.59%。整个培养期间,添加Fe2+后,XR和QR土壤CO2累积排放量分别降低了43.87%和22.14%。综上,我国南方富含铁氧化物的红壤具有更高的固碳减排潜力。     

密度调控对长白落叶松人工林土壤呼吸的影响

为探明密度调控对北温带森林土壤呼吸的影响机制,以长白落叶松人工林为研究对象,选择4种林分密度P₁(300~350株/hm2)、P₂(500~550株/hm2)、P₃(600~650株/hm2)和P₄(850~900株/hm2),使用LI-6400便携式土壤呼吸测定仪对其生长季(5—10月)土壤呼吸速率进行测定。结果表明:不同密度林分生长季土壤呼吸速率均呈现明显的季节动态,最高值均出现在8月末,最低值出现在10月中旬;不同密度林分生长季土壤呼吸速率及土壤累积CO₂排放量均随林分密度增大而显著降低(P＜0.05)。不同密度林分土壤呼吸与土壤温度之间均呈极显著的指数相关(P＜0.001),但与土壤含水量之间相关关系不显著(P＞0.05);双因素模型拟合效果更优,土壤温度和含水量共同解释了土壤呼吸速率的73.1%~81.0%。土壤呼吸温度敏感系数Q₁₀值表现为:在300~350株/hm2时最低(2.41),500~550株/hm2最高(3.32)。生物因子随着林分密度的增大而显著增大(P＜0.05),非生物因子均随林分密度增大而显著减小(P＜0.05);生长季土壤累积CO₂排放量与生物因子达到极显著负相关(P＜0.001),与非生物因子均达到极显著正相关(P＜0.001)。逐步线性回归分析表明,生长季凋落物量、土壤有机碳、微生物生物量碳含量和土壤全氮含量与土壤呼吸的关系最为密切。综上所述,不同密度林分之间土壤温度及含水量、生物及非生物因子的差异是导致土壤CO₂排放产生差异的主要原因。在森林经营管理中,为减小森林土壤CO₂的排放量,应将林分密度设置为850~900株/hm2。      

红参加工中皂苷的脱羧降解反应及其产物的研究

从鲜人参中提取分离出天然皂苷,模拟红参加工工艺过程,探讨红参加工中天然皂苷成分转化过程,以揭示出皂苷成分转化机理。方法：将红参粉以甲醇提取,乙醚脱脂,正丁醇萃取;水层通过大孔树脂（Ｄ１０１型）吸附,水洗除去水溶性发质和糖分。再经过硅胶柱层析和阳离子交换树脂柱层析,获得丙二酸单酰基人参皂苷。模拟红参加工工艺过程得转化物,对该转化物进行分离鉴定,诸如化学试验、ＩＲ、ＦＤ－ＭＳ等仪器分析。结果表明：从鲜人参中分离出丙二酸单酰基人参皂苷－Ｒｂ２和－Ｒｂ２等皂苷,通过模拟红参加工试验发现在７５℃烘干过程,丙二酸单酰基人参皂苷－Ｒｂ２转化为乙酰基人参皂苷－Ｒｂ２,即人参皂苷Ｒｓ１。结论：人参皂苷Ｒｓ１是红参加工烘干阶段产生的,对其分解产物的分析有二氧化碳放出,说明该反应是丙二酸单酰基人参皂苷上的丙二元到遇热发生脱羧降解反应     

Activity of CeOx and TiOx nanoparticles grown on Au(111) in the water-gas shift reaction

The high performance of Au-CeO2 and Au-TiO2 catalysts in the water-gas shift (WGS) reaction (H2O + CO-->H2 + CO2) relies heavily on the direct participation of the oxide in the catalytic process. Although clean Au(111) is not catalytically active for the WGS, gold surfaces that are 20 to 30% covered by ceria or titania nanoparticles have activities comparable to those of good WGS catalysts such as Cu(111) or Cu(100). In TiO(2-x)/Au(111) and CeO(2-x)/Au(111), water dissociates on O vacancies of the oxide nanoparticles, CO adsorbs on Au sites located nearby, and subsequent reaction steps take place at the metal-oxide interface. In these inverse catalysts, the moderate chemical activity of bulk gold is coupled to that of a more reactive oxide.     

Crystal structure of a carbon monoxide dehydrogenase reveals a [Ni-4Fe-5S] cluster

The homodimeric nickel-containing CO dehydrogenase from the anaerobic bacterium Carboxydothermus hydrogenoformans catalyzes the oxidation of CO to CO2. A crystal structure of the reduced enzyme has been solved at 1.6 angstrom resolution. This structure represents the prototype for Ni-containing CO dehydrogenases from anaerobic bacteria and archaea. It contains five metal clusters of which clusters B, B', and a subunit-bridging, surface-exposed cluster D are cubane-type [4Fe-4S] clusters. The active-site clusters C and C' are novel, asymmetric [Ni-4Fe-5S] clusters. Their integral Ni ion, which is the likely site of CO oxidation, is coordinated by four sulfur ligands with square planar geometry.     

红桦幼苗干物质分配与营养对CO_2升高的响应

采用控制环境生长室研究了2个密度水平下CO2浓度升高对红桦幼苗干物质分配与营养的影响,并分析了红桦干物质分配与养分浓度的关系。试验设2个CO2浓度水平(350和700μmol.mol-1),每个CO2浓度水平下又设28和84株.m-2两个密度水平。结果表明,升高CO2浓度可促进红桦幼苗生物量的增加,但对根冠比没有显著影响。促进效应的存在是由于短期内CO2浓度升高后植物大量吸收了土壤速效养分。CO2浓度的升高加速了土壤养分的消耗,但植物各器官N、P含量均下降,这是由生物量迅速增加产生的稀释效应造成的。     

Atmospheric carbon dioxide levels over phanerozoic time

A new model has been constructed for calculating the level of atmospheric CO(2) during the past 570 million years. A series of successive steady states for CO(2) is used in order to calculate CO(2) level from a feedback function for the weathering of silicate minerals. Processes considered are: sedimentary burial of organic matter and carbonates; continental weathering of silicates, carbonates, and organic matter; and volcanic and metamorphic degassing of CO(2). Sediment burial rates are calculated with the use of an isotope mass-balance model and carbon isotopic data on ancient seawater. Weathering rates are calculated from estimates of past changes in continental land area, mean elevation, and river runoff combined with estimates of the effects of the evolution of vascular land plants. Past degassing rates are estimated from changes in the rate of generation of sea floor and the shift of carbonate deposition from platforms to the deep sea. The model results indicate that CO(2) levels were high during the Mesozoic and early Paleozoic and low during the Permo-Carboniferous and late Cenozoic. These results correspond to independently deduced Phanerozoic paleoclimates and support the notion that the atmospheric CO(2) greenhouse mechanism is a major control on climate over very long time scales.     

球孢白僵菌对小菜蛾呼吸作用的影响

利用红外 CO2 分析仪测定了小菜蛾感染球孢白僵菌后呼吸节律的变化 .结果表明 ,小菜蛾呼吸节律属于不规则波动型 ,染病幼虫呼出的 CO2 量显著低于对照组 .说明感染球孢白僵菌后 ,小菜蛾幼虫的生理代谢受到干扰 ,呼吸代谢水平降低     

CO2浓度升高对红桦幼苗树皮和去皮树干特征的影响

研究了高(HD)、低(LD)两个种植密度下红桦幼苗的树皮和去皮树干特征对CO2升高的响应。结果表明,不论是否达到显著水平,树皮厚度、树皮基部横截面积和树皮体积均受到CO2升高的促进作用,但是受到种植密度升高的负作用。低密度处理中,CO2升高对去皮树干的大部分特征没有显著影响,高密度处理中,CO2升高对去皮树干特征产生了显著影响。在两个CO2处理下,所有的去皮树干的特征参数都受种植密度增加的影响而降低。此外,研究结果还发现树皮和树干对CO2升高和/或种植密度的反应程度不同,但反应方向一致。由于本实验是在控制环境生长室中对幼苗进行的,因而实验结果不宜外推到自然界生长的成年树木上。     

Alkali-stabilized Pt-OHx species catalyze low-temperature water-gas shift reactions

We report that alkali ions (sodium or potassium) added in small amounts activate platinum adsorbed on alumina or silica for the low-temperature water-gas shift (WGS) reaction (H(2)O + CO → H(2) + CO(2)) used for producing H(2). The alkali ion-associated surface OH groups are activated by CO at low temperatures (~100°C) in the presence of atomically dispersed platinum. Both experimental evidence and density functional theory calculations suggest that a partially oxidized Pt-alkali-O(x)(OH)(y) species is the active site for the low-temperature Pt-catalyzed WGS reaction. These findings are useful for the design of highly active and stable WGS catalysts that contain only trace amounts of a precious metal without the need for a reducible oxide support such as ceria.     

Doppler interpretation of quasar red shifts

The hypothesis that the quasistellar sources (quasars) are local objects moving with velocities close to the speed of light is examined. Provided there is no observational cutoff on apparent bolometric magnitude for the quasars, the transverse Doppler effect leads to the expectation of fewer blue shifts than red shifts for an isotropic distribution of velocities. Such a distribution also yields a function N(z), the number of objects with red shift less than z which is not inconsistent with the present data. On the basis of two extreme assumptions concerning the origin of such rapidly moving sources, we computed curves of red shift plotted against magnitude. In particular, the curve obtained on the assumption that the quasars originated from an explosion in or nearby our own galaxy is in as good agreement with the observations as the curve of cosmological red shift plotted against magnitude.     

Infrared Reflection-Absorption Spectroscopy and STM Studies of Model Silica-Supported Copper Catalysts

The structure of model silica-supported copper catalysts has been investigated with scanning tunneling microscopy (STM) and infrared reflection-absorption spectroscopy (IRAS). The IRAS studies of CO on the model silica-supported copper catalysts indicate that there are several types of copper clusters with surface structures similar to (111), (110), and other high-index planes of single-crystal copper. The STM studies show several types of copper clusters on silica and reveal images of metal clusters on an amorphous oxide support with atomic resolution.     

纳米铜/聚苯乙烯-丁二烯(SBS)杂化材料研究

采用脉冲激光轰击法连续制备了纳米铜,进而采用共混法连续制备了纳米铜/SBS杂化材料,用UV-V is、TEM、荧光光谱、FT-IR和TG-DTA对其结构和性质进行了表征.结果表明因为金属铜纳米颗粒的引入表面原子配位不足,表面能极高,活性高,很容易与SBS链段中的不饱和键相互作用,导致UV-V is吸收峰的移动和消失,SBS分子的荧光部分淬灭,整体荧光强度下降,与C=C双键相连的C-H红外变形振动吸收频率的降低;TEM观察显示由于聚合物链段的空间位阻及聚合物链段与铜纳米颗粒的相互作用对铜纳米颗粒的团聚产生阻碍,使杂化材料中铜纳米颗粒的尺寸受到限制,故铜纳米颗粒在SBS在中有较高的稳定性.TG-DTA结果发现Cu/SBS杂化材料的分解温度比SBS高,高温失重较小,热稳定性较好,这是由于Cu纳米粒子和SBS中的C=C双键之间的相互作用,形成具有桥键的结构,使聚合物SBS大分子间的作用力增大所致.     

8种新疆产干果的红外光谱特征研究

分析了新疆产8种干果的红外光谱特征。这8种干果可分为两类，其红外图谱在官能团区有很大差异。巴旦木、核桃仁、花生仁、带壳杏仁富含蛋白质和脂类物质，红外图谱显示出在2914，2847cm^-1附近的CH伸缩振动和1742cm^-1附近的C=O伸缩振动；枸杞子、红枣、葡萄干和无花果干富含多糖、蛋白类物质，其红外图谱显示出在3370cm^-1附近的OH变形振动、NH伸缩振动和2920cm^-1附近的CH伸缩振动。     

微切助互作技术辅助提取辣椒红色素的研究

为研究微切助互作技术辅助提取辣椒中辣椒红色素的最佳工艺条件,本试验以辣椒红色素的吸光度和色价为指标,考察微切助互作技术辅助提取辣椒中辣椒红色素的影响因素,并通过正交试验确定最佳工艺。结果表明：最佳提取条件为Na2CO3助剂用量为5％（w／w）,研磨时间为40min,溶液95％乙醇,料液比为1：70（g：ml）。在该条件下检测红色素色价,较热回流法提高了15．09％。     

不同改良剂对镉污染土壤的改良效果和对水稻光合特性的影响

采用盆栽试验,研究赤泥、石灰和海泡石对Cd污染土壤的改良效果和水稻光合特性的影响。结果表明:施赤泥、石灰和海泡石均能有效促进土壤交换态Cd的稳定,有利于Cd的固定,其中以赤泥对Cd的钝化效果最佳;与对照相比,赤泥处理的水稻增产幅度较大,为11.41%,海泡石处理的水稻产量略有提高,石灰处理的水稻产量略有下降;不同改良剂均能增加水稻剑叶的叶绿素含量(SPAD值)、气孔导度、净光合速率、胞间CO2浓度及蒸腾速率,其中以施赤泥处理效果最好,分别比对照提高6.63%、8.59%、6.93%、11.95%、5.42%;不同改良剂处理水稻剑叶面积均有不同程度的上升,添加赤泥更能缓解Cd污染对水稻生长的影响。     

管道输送CO2准临界特性及安全控制

管输CO2在临界点附近会出现物性参数发生剧烈波动的准临界特性,进而影响管道安全稳定运行。采用密度作为基准参数,拟合出大规模管输CO2密度波动最剧烈处的准临界温度关系式,分析杂质对管输CO2准临界温度关系的影响并提出安全控制方案,以国内首条CO2管道示范工程为实例,提出安全输送操作建议。研究表明：非极性及弱极性杂质将使准临界温度线向低温方向偏移,强极性杂质及水汽将使准临界温度线向高温方向偏移;管输含不同杂质的多组分CO2时,需要采用不同的起始温度、压力,以避免管内工况接近准临界温度线或进入两相区,采用高于14MPa压力输送,管内介质可以保持安全稳定流动。国内首条大规模长距离超临界CO2管道示范工程输送燃煤电厂排放的烟气,需采用输送含非极性杂质CO2对应的安全控制技术。（图4,表1,参18）