986 resultados para 37.014[82]
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贝类养殖作为我国传统的海水养殖产业,在我国沿海地区的经济发展中起重要作用。但由于近年来养殖扇贝病害的不断发生,不仅造成了巨大的经济损失,而且直接威胁到现有养殖产业的生存和发展。目前认为,机体抗病能力的下降是发生流行性死亡的主要原因之一。因此,深入研究扇贝免疫防御特性,能更好地了解和解决贝类养殖中的病害问题。本文比较了健康状态和重金属污染以及高温胁迫下海湾扇贝和栉孔扇贝部分免疫指标的变化,并对同龄不同大小的栉孔扇贝的部分免疫指标进行了比较,以期更好的了解贝类的防御机制,为扇贝病害防治提供资料。研究结果如下: 用流式细胞仪技术对血细胞死亡率、细胞吞噬率和呼吸爆发进行了测定,发现健康状态下两种扇贝的细胞死亡率相差不大,海湾扇贝为4.83%,栉孔扇贝为4.95%;细胞吞噬率差异显著(P<0.05),海湾扇贝为26.73%,栉孔扇贝为19.89%;呼吸爆发的基础值相差也不大,海湾扇贝为1.94,栉孔扇贝为1.56。另外用免疫化学方法对健康状态下栉孔扇贝和海湾扇贝血淋巴和肝胰腺中SOD、ACP活性和MDA含量也进行了测定与比较。发现在血淋巴和肝胰腺中,两种扇贝SOD活性均存在显著差异(P<0.05),其中海湾扇贝分别为995.43和113.99,栉孔扇贝分别为446.64和40.6;血淋巴和肝胰腺中ACP活性差异显著(P<0.05),海湾扇贝分别为90.19和432.36,栉孔扇贝分别为73.26和146.63;血淋巴中和肝胰腺中MDA含量差异不显著(P>0.05),海湾扇贝分别为3.37和92.46,栉孔扇贝分别为2.17和28.96。实验结果说明,海湾扇贝对细菌等异物的吞噬和杀灭能力以及机体自身的抗氧化能力高于栉孔扇贝,这为海湾扇贝比栉孔扇贝具有更高的抗逆性提供了证据。 用相同的方法对不同浓度(0, 0.2, 0.3, 0.5 mg L-1) Pb2+溶液浸泡后的栉孔扇贝和海湾扇贝的血细胞死亡率、细胞吞噬率和呼吸爆发进行了检测,同时测定了Pb2+处理后肝胰腺中SOD、ACP活性和MDA含量的变化。结果表明,栉孔扇贝的血细胞死亡率与对照组相比有上升趋势,且随着Pb2+浓度的增加而显著增加,而海湾扇贝在相同条件Pb2+的胁迫下,血细胞的死亡率明显低于栉孔扇贝。栉孔扇贝各实验组细胞吞噬率均低于对照组,而海湾扇贝在低浓度的Pb2+浸泡后,细胞的吞噬率与对照组相比有所降低,但随着浓度的继续增加,细胞的吞噬率反而上升,甚至略高于对照组。栉孔扇贝血细胞的呼吸爆发在Pb2+胁迫后较对照组有所升高,但随着浓度的增加,呼吸爆发有下降的趋势,而海湾扇贝的呼吸爆发随着Pb2+浓度的增加而显著增加。对两种扇贝体液免疫指标的测定发现,各实验组SOD的活性均比对照组高,且海湾扇贝的SOD活性高于栉孔扇贝;随着Pb2+浓度的增加,各实验组ACP的活性一直呈上升趋势,且海湾扇贝的ACP活性也高于栉孔扇贝;Pb2+处理后MDA的含量均显著增加,其中栉孔扇贝MDA含量的增幅明显高于海湾扇贝。该结果说明,Pb2+对两种扇贝的免疫系统都有一定的影响,但相同剂量的Pb2+对两种扇贝的毒害程度不同,海湾扇贝对Pb2+的耐受性似乎高于栉孔扇贝。 对海湾扇贝和栉孔扇贝的升温刺激实验发现,当养殖水体的温度从18℃缓慢升高到30℃后,栉孔扇贝在第三天开始出现大量死亡现象,而海湾扇贝未出现死亡。因而本文只对升温前后的海湾扇贝进行了细胞死亡率、吞噬率和呼吸爆发的测定和比较。结果发现,与升温前相比,血细胞的死亡率在温度升高后略有增加,但差异不显著(P>0.05);而细胞吞噬率在温度升高后显著下降;通过对呼吸爆发积聚的活性氧(Reactive Oxygen Species,ROS)的测定发现,升温后血细胞的ROS含量显著高于升温前(P<0.05)。该结果表明,高温会影响血细胞的功能,使机体的免疫防御能力下降,从而导致病害的发生。 另外,本文对同龄不同大小的栉孔扇贝的血细胞吞噬率以及血淋巴和肝胰腺中SOD、ACP活性和MDA含量进行了测定与比较。结果发现: 小扇贝的血细胞吞噬率略高于大扇贝,分别达到了22.82和20.96;在血淋巴及肝胰脏中,两组扇贝SOD酶的活性均差异显著(P<0.05),小扇贝分别为613.88和102.01,大扇贝分别为356.15和50.22;血淋巴中小扇贝ACP的活性极显著的高于大扇贝(P<0.01),分别为44.3和2.91,但肝胰腺中大扇贝和小扇贝ACP的活性相差不大,大扇贝为455.75,小扇贝为485.33;大扇贝和小扇贝血淋巴和肝胰脏中MDA含量相差不大,大扇贝分别为2.67和31.83,小扇贝分别为3.17和35.33。该结果说明,小扇贝对细菌等异物的吞噬和杀灭能力以及机体自身的抗氧化能力高于大扇贝,这为生长与抗逆性相颉抗提供了依据。
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鱼类胚胎由于其自身结构特征:体积大、含水量高、多室结构等,迄今超低温保存尚未成功。超低温保存过程中所造成的冷冻损伤是制约鱼类胚胎超低温保存成功与否的关键,具体表现为渗透压影响、抗冻剂毒性、冰晶损伤等。系统研究并阐明鱼类胚胎冷冻损伤机理,是成功建立鱼类胚胎超低温保存技术的基础。本论文主要针对胚胎对渗透压的耐受性、抗冻剂对胚胎的渗透性、降温速率对胚胎内外冰晶形成温度的影响等冷冻损伤机理进行了系统研究,主要研究结果如下: 1.通过检测胚胎在不同浓度人工海水(0%、25%、50%、75%、1×、2×、3×、4×,渗透压范围0~3740 mOsm/kg)中的孵化率,确定了真鲷不同发育时期胚胎对渗透压的耐受范围,以及心跳期胚胎浸泡不同时间对渗透压的耐受范围。结果显示:①真鲷2-4细胞期、原肠期、10-14体节期胚胎、心跳期和出膜前期胚胎孵化率>50%时渗透压的范围依次为:919~1391 mOsm/kg、919~1391 mOsm/kg、462 ~1391 mOsm/kg、232~1878 mOsm/kg和692~1391 mOsm/kg,表明心跳期胚胎对渗透压变化的耐受范围最广;②在不同浓度人工海水中分别浸泡10 min、30 min、1 h、5 h和10 h后,真鲷胚胎孵化率无显著变化的渗透压范围分别为0~2804 mOsm/kg、0~1878 mOsm/kg、232~1391 mOsm/kg、232~1391 mOsm/kg和919~1391 mOsm/kg;结果表明心跳期胚胎对渗透压的耐受范围随浸泡时间的延长而减小。 2.采用毛细管电泳技术检测胚胎内部DMSO的浓度,并且分析了胚胎孵化率和胚胎内部DMSO的浓度随浸泡时间变化与外部抗冻剂的关系。结果表明胚胎孵化率随胚胎外部抗冻剂溶液浓度和浸泡时间的增加而降低;胚胎内部DMSO浓度随胚胎外部抗冻剂溶液浓度和浸泡时间的增加而增加。对胚胎孵化率(y1)随抗冻剂溶液浓度(x)的变化进行一元三次多项式回归,当浸泡时间分别为10 min、30 min和60 min时,回归方程依次为:y1 = -2832.7x3 + 575.01x2 - 37.011x + 99.641(R2 = 0.9722);y1 = 30288x3 - 16322x2 + 2077.3x + 27.603(R2 = 0.9876);y1 = 16052x3 - 5985.2x2 - 32.696x + 119.6(R2 = 0.9124)。对胚胎内部DMSO浓度(y2)随抗冻剂溶液浓度(x)的变化进行回归,当浸泡时间分别为10 min、30 min和60 min时,回归方程依次为:y2 = 0.2584e6.7294x(R2 = 0.9876);y2 = 0.2521e10.964x(R2 = 0.9644);y2 = 0.4054e10.95x(R2 = 0.8954)。 3. 利用低温显微镜观察了不同降温速率(20、40、60、80、100、120℃/min)对胚胎内外冰晶形成温度的影响。胚胎外部冰晶形成温度(TEIF)随降温速率的增加显著下降,在降温速率大于80℃/min之后,TEIF随降温速率增加而降低的幅度减小;胚胎内部冰晶形成温度(TIIF)在降温速率小于80℃/min 时随降温速率的升高而降低,在降温速率大于80℃/min 时随降温速率的升高而升高;胚胎内外冰晶形成温度差值(TEIF - TIIF)在降温速率小于80℃/min时随降温速率的升高而增大,在降温速率大于80℃/min时随降温速率的升高而减小。 4. 在低温显微镜下观察了真鲷胚胎低温保存中有复活胚胎记录的保存方法在冷冻解冻过程中的冰晶形成过程,结果表明:①在冷冻过程中,玻璃化法冷冻的胚胎的内部冰晶形成温度(-53.70,-64.33℃)显著低于程序降温法(-17.51,-21.40℃);而且在玻璃化法冷冻的胚胎内部冰晶形成温度高于外部冰晶后形成(-70.30℃),程序降温法中则相反,胚胎内部冰晶形成温度显著低于外部冰晶形成温度(-4.93,-5.00℃);玻璃化法中,40%PG冷冻的胚胎外部溶液出现玻璃化现象,其他组均未出现;②在解冻过程中,各组均出现重结晶现象;解冻后,玻璃化法的胚胎完整率(62.82%)远高于程序降温法(9.21%)。
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From November 2002 to 2006, five cruises were undertaken in the Yangtze River Estuary and the adjacent East China Sea to compare the nutrient concentrations, ratios and potential nutrient limitation of phytoplankton growth before and after impoundment (June 2003) of the Three Gorges Dam (TGD). Concentrations of dissolved inorganic nitrogen (DIN), soluble reactive phosphorus (SRP) and total nitrogen (TN) exhibited an increasing trend from 2002 to 2006. In contrast, total phosphorus (TP) concentration exhibited a decreasing trend. The mean concentrations of DIN, SRP, and TN in the total study area increased from 21.4 mu M, 0.9 mu M, and 41.8 mu M in 2002 to 37.5 mu M, 1.3 mu M. and 82.2 mu M in 2006, respectively. while TP decreased from 2.1 mu M to 1.7 mu M. The concentration of dissolved reactive silica (DRSi) had no major fluctuations and the differences were not significant. The mean concentration of DRSi in the total study area ranged from 52.5 to 92.3 mu M. The Si:N ratio decreased significantly from 2.7 in 2002 to 1.3 in 2006, while TN: TP ratio increased from 22.1 to 80.3. The area of potential P limitation of phytoplankton growth expanded after 2003 and potential Si limitation appeared in 2005 and 2006. Potential P limitation mainly occurred in an area of salinity less than 30 after 2003, while potential Si limitation occurred where the salinity was greater than 30. By comparison with historical data, the concentrations of nitrate and SRP in this upper estuary during November 1980-2006 increased obviously after impoundment of TGD but DRSi decreased. Meanwhile, the ratios of N:P, Si:N and Si:P decreased obviously. (c) 2009 Elsevier B.V. All rights reserved.
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The nitric oxide synthase (NOS) activity in the haemocytes of shrimps Fenneropenaeus chinensis (Osbeck) and Marsupenaeus japonicus (Bate) was Studied after white spot syndrome virus (WSSV) infection to determine its characteristics in response to virus infection. First, the NOS activity in haemocytes of shrimps was determined by the means of NBT reduction and changes in cell conformation. And the variations of NOS activity in shrimps after challenge with WSSV intramuscularly were evaluated through the analysis Of L-citrulline and total nitrite/nitrate (both as NO derivates) concentrations. The result showed that NOS activity in the haemocytes of F chinensis increased slightly from 0 to 12 h postchallenge, indicated by the variations Of L-Citrulline (from 11.15 +/- 0.10 to 12.08 +/- 0.64 mu M) and total nitrite/nitrate concentrations (from 10.45 +/- 0.65 to 12.67 +/- 0.52 mu M). Then it decreased sharply till the end of the experiment (84 h postchallenge), the concentrations Of L-Citrulline and total nitrite/nitrate at 84 It were 1.58 +/- 0.24 and 2.69 +/- 0.70 mu M, respectively. The LPS-stimulated NOS activity kept constant during the experiment. However, in M. japonicus, the NOS activity kept increasing during the first 72 It postchallenge, the concentrations Of L-Citrulline and total nitrite/nitrate increased from 7.82 +/- 0.77 at 0 h to 10.79 +/- 0.50 mu M at 72 h, and from 8.98 +/- 0.43 at 0 h to 11.20 +/- 0.37 mu M at 72 h, respectively. Then it decreased till the end of the experiment (216 h postchallenge), and the concentrations of L-Citrulline and total nitrite/nitrate at 216 h were 5.66 +/- 0.27 and 4.68 +/- 0.16 mu M, respectively. More importantly, an apparent increase of I-PS-stimulated NOS activity was observed in M japonicus at 48 h postchallenge, which was about 4 times higher than that in the control group of health shrimps. In correspondence with the difference of NOS activity between the two species of shrimps, the Cumulative mortalities of the shrimps were also different. All shrimps of F. chinensis in the mortality experiment died in 66 h, much more quickly than M. japonicus, Whose accumulative mortality reached 100% after 240 h. Data here reported let us hypothesize that NOS activity in the haemocytes of shrimps F chinensis and M. japonicus responses to WSSV infection differently, and this might be one of the reasons for the different susceptibility of F chinensis and M. japonicus to WSSV infection. (c) 2005 Elsevier Inc. All rights reserved.
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主要依据中国科学院西北高原生物研究所青藏高原生物标本馆内所存标本为基础,结合对相关资料的全面收集,整理出青海特有植物82种和37变种,隶属19科54属.文中除了分科、属列出每个种或种下类型在青海境内到县一级的产地、生境和海拔高度等以外,还列出了它们的原始文献和可供引证、查阅的标本号.是研究青海高原植物区系的组成、性质和特点以及发生和演变规律等方面问题的基础资料.
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根据天然草地退化程度的差异,采用松耙+补播+施肥+封育(退化较严重的草地)、封育+施肥(轻度退化草地)等措施,植物群落物种组成、多样性等特征值及其植被盖度发生明显变化.研究第2年结果表明,物种数封育+施肥处理最高(32种),对照居中(26种),补播+施肥处理最低(13种);多样性指数大小依次为封育+施肥(3.126)、对照(2.819)、补播+施肥(1.494);均匀度指数大小依次为封育+施肥(0.902)、对照(0.865)、补播+施肥(0.582);群落总盖度大小依次为封育+施肥(85.9%)、补播+施肥(79.7%)、对照(72.9%);补播+施肥+封育处理后地上生物量最大(460.65 g/m2),原生植被+封育+施肥处理居中(310.14 g/m2),对照最低(178.96 g/m2);地下生物量大小依次为封育+施肥(6 920.37 g/m2)、补播+施肥(1 458.96 g/m2)、对照(828.91 g/m2);补播+施肥+封育处理优良牧草较对照提高近50倍,杂草类减少82.81%,封育+施肥处理较对照良牧草比例提高48倍,杂草类比例减少80.46%.半人工草地通过灭除杂草和施肥相结合的示范试验表明:单纯进行灭杂,地上生物量减少,灭杂和施肥相结合不仅可提高地上生物量,而且可提高优良牧草的比例;不同处理区土壤养分含量各不相同,其中封育+施肥处理全氮、全碳、有机碳最高,对照居中,补播+施肥较低.
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基于1997~1999年野外实验,对高寒草甸小云雀和黄嘴朱顶雀两种雀形目鸟的窝雏数进行增减处理。结果表明,对照组的幼鸟生长率和离巢体重都大于增加组,说明窝雏数增加后,幼鸟质量下降。随着窝雏数增加,这两种幼鸟生长率显著下降(小云雀:r = -0.965, P = 0.035 < 0.05;朱顶雀:r = -0.828, P = 0.022 < 0.05)。窝雏数改变对小云雀幼鸟出飞重影响不显著(r = -0.418, P = 0.528 > 0.05),而对黄嘴朱顶雀有显著的影响(r = -0.901,P = 0.014 < 0.05)。
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Emodin, a natural anthraquinone compound isolated from the rhizome of rhubarb, is reported to suppress the growth of tumor in many clinical situations. In this study, we focused on the effect of emodin in human breast cancer BCap-37 cells and further understand the underlying molecular mechanism in treating breast cancer. Using MTT assay and flow cytometry, we demonstrated the critical role of emodin in the suppression of the proliferation of BCap-37 cells based on a concentration- and time-dependent manner. The increase of apoptotic rate was also observed after incubation of BCap-37 cells on emodin at 20 mu M and 50 mu M for 48 h. The cells exhibited typical apoptotic features including cellular morphological change, chromatin condensation and membrane blebbing. The results of the study further showed that Bcl-2 level decreased, while Bax and cytosolic cytochrome c levels in sample cells increased after the emodin treatment by using Western blot. The decline in the Bcl-2/Bax ratio and the increase of cytosolic cytochrome c concentration were consistent with the increase of the apoptotic ratio. The results strongly suggest that the disruption of the mitochondrial signaling pathway was involved in emodin-induced apoptosis in BCap-37 cells.
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This paper selected the Taklamakan Desert and the Badain Jaran Desert as the research areas, tested the carbonate content of surface-sand samples of dunes using Eijkelkamp carbonate goniophotometer, and analyzed the spatial-distribution characteristics of carbonate and estimated the carbonate-stock and secondary carbonate-stock in 1m depth of surface sand in the Taklamakan Desert and the Badain Jaran Desert. In addition, the paper test XRD, SEM, TDA, stable carbon isotope and radioactive strontium isotope of lacustrine deposits in the Taklamakan Desert and carbonates, such as kunkar, root canal, lacustrine deposits, sinter and calcrete, in the Badain Jaran Desert. Resting on the achievements by our predecessors, it analyzed the mineral-composition differences of the carbonates, calculated the contents of secondary carbonate and, furthermore, evaluated their potential of sequestration of CO2 in the atmosphere. The overall goal of this study was to increase our understanding of soil carbonate in the context of carbon sequestration in the arid region in China. That is, to advance our understanding about whether or not secondary carbonate in desert is a sink for atmospheric CO2. The following viewpoints were obtained: 1 Carbonate contents of surface-sand samples decend from the south to the north of the Taklamakan Desert. The minimum lies in the south and the maxmum in the mid. Carbonate content of surface-sand of megadunes in the Badain Jaran Desert has low value generally in the dune-crest and the base of slope, and large value in the mid. The average of Carbonate contents of all sorts of collected samples in the same area of the Taklamakan Desert has small diffetences. The average is about 9%. 2 Using carbonate contents as key parameters, calculate the carbon-stock of carbonates in 1m depth of surface sand in the Taklamakan Desert and the Badain Jaran Deser.They are 1.13Pg and 0.19 Pg respectively. There are 0.53Pg and 0.088Pg carbon-stock of secondary-carbonates in 1m depth of surface sand in the Taklamakan Desert and the Badain Jaran Desert. 3 Through testing data from XRD (X-ray diffraction)and TAD ( Thermal Analysis Data), the most significant conclusion derived from is that the main mineral ingredient is calcite in different carbonate substances in arid regions, From the SEM(Scanning electron microscopy ) images, can obtains the information about the micro environment of different carbonate forms in which they can grow. 4 Selected gas by termal cracking and traditional phosphoric acid method, their δ13C show that δ13C is a good parameter to indicate the micro environment in which different secondary carbonate forms. From the δ13C of the same type samples, if the redeposit degree is hard, theδ13C is light, the redeposit degree is weak, the δ13C is heave. and the δ13C of the different type samples, δ13C is mainly controlled by the micro environment in which secondary formed. if the procedure is characterized by redeposit and dissolve of marine facies carbonate, δ13C is heavy, it is characterized by CO2 which produced by plant respiration,δ13C is light. 5 From the δ13C of lacustrine deposit in the different grain size, there exsit certain differences in their micro environment and secondary degree among different grain size in the same grade. 6 The secondary carbonate content of lacustrine deposits in Taklimakan Desert is 47.26%. And those of root canal, sinter, calcrete, kunkar, lacustrine deposit and surface sand in Badain Jaran Desert are 91.74%, 78.46%, 76.26%, 87.87%, 85.37%and 46.49%, respectively. Of different grain size samples, the secondary carbonate contents of coarse fraction (20-63μm), sub-coarse fraction (5-20μm) and fine fraction (<5μm) are 80.10%, 47.2%and 50.07%, respectively. 7 There is no obvious relevance betweenδ13C of secondary carbonate and the content of secondary carbonate,theδ13C of secondary carbonate mainly reflects the parameters of secondary process, the content of secondary carbonate reflects difference of secondary degree.. 8 Silicates potentially supply 3.4 pencent calcium source during forming process of lacustrine deposits in Taklimakan Desert. If calcium source is mainly supplied by goundwater, it can be calculated that about 5.18 %, 6.13%, 5.68%, 5.64 % and 6.82% silicates supply calcium source respectively for root canal, kunkar, lacustrine deposit, calcrete and sinter, during the forming process of different kinds of carbonates in Badain Jaran Desert.
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使用改进的巯基棉分离流程和^74硒-^77硒双稀释剂,在氢化物(HG)-多接收器电感耦合等离子体质谱仪(MC—ICP—MS)实现了高精度硒同位素组成的测定。巯基棉用于分离样品基质中的硒,随后使用HNO3+H2O2消除干扰的有机质,^74硒-^77硒双稀释剂校正样品分离和质谱测定过程中的硒同位素质量分馏。硒标准溶液NIST SRM5149和MH495几个月的测定表明,该方法的外精度为0.1‰(2σ),样品的外精度为0.15‰~0.2‰(2σ)。以TCF分离硒的平均回收率85%计算,最小硒需要量为20ng。实验结果以相对于NIST SRM3149的δ^82/76Se表达,δ^82/76MH98/SRM3149=-3.44±0.1‰(2σ),优于已发表的数据δ^82/79MH495/SRM3149=-3.04±0.5‰。测定样品的δ82/76 SRM3149为-13.53‰~11.37‰,为硒同位素在环境、农业、生命和地球科学中的拓展应用与发展奠定了基础.
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利用被动微波遥感亮度温度数据反演月壤厚度是“嫦娥”探月工程的科学目标之一,也是人类探测月壤厚度的一种新的尝试。深入研究月表太阳辐射、月球内部热流以及月表温度的分布和变化规律,是解译遥感数据,反演月壤厚度的前提条件,也为进一步开展月球探测、开发利用月球资源乃至建立月球基地相关研究工作提供必要的参考。 本文根据月表有效太阳辐照度与太阳常数、日月距离和太阳辐射入射角的关系,建立了月表有效太阳辐照度的实时模型如下: (1) 其中, (2) (3) 通过对月表有效太阳辐照度实时模型的各个参数分析发现,影响月表有效太阳辐照度变化的主要因素是日地距离和太阳辐射入射角的变化。对模型的误差分析表明,从1950年到2050年的100年内,月表有效太阳辐照度计算结果的误差百分比小于0.28%,能更准确地反映月表有效太阳辐照度的变化情况。从2007年月表有效太阳辐照度的计算结果发现,该年内的月表有效太阳辐照度变化在1321.5~1416.6 W•m-2之间,平均为1368.0 W•m-2,一个月内的变化最小幅度为6.0 W•m-2,最大幅度为23.6 W•m-2。 在月表有效太阳辐照度的实时模型基础上,根据能量守恒和Stefan-Boltzmann定律,本文还得出了月表温度分布模型如下: (4) 其中,初始条件由下式决定, (5) 通过与月表温度实际观测结果的比较发现,当月表反射率、热发射率和热惯量分别取0.127、0.94和125 J•m-2•s-1/2•K-1时,模型的计算结果与实际观测值比较符合,能较好地预测理想条件下的月表温度。 月表热参数研究的一个重要应用就是解译对月被动微波遥感的亮度温度数据。在对月被动微波遥感探测中,辐射计获得的亮度温度反映了月球表层的热辐射特性。月球表层的热辐射与其自身的热状况紧密相关,结合文中建立的月表热参数模型,根据辐射传播理论进一步分析了对月微波遥感探测中,月球表层在不同情况下对亮度温度的贡献,确定了亮度温度随月表温度和月壤厚度的变化关系,对被动微波遥感探测月壤厚度的可能性和可能达到的精度进行了估算。 对月球表层的热辐射传播的分析发现,对月被动微波遥感探测获得的亮度温度受月球表层热辐射的控制,与月壤厚度具有指数相关性,并受到月表温度的影响。当月壤和月岩的复介电常数分别为2 + 0.005 j和9 + 1 j、相对磁导率均为1时,对应3.0GHz、7.8GHz、19.35GHz和37.0GHz四个频率的亮度温度与月壤厚度及月表温度的关系可分别近似表示为, 3.0GHz亮度温度: (6) 7.8GHz亮度温度: (7) 19.35GHz亮度温度: (8) 37.0GHz亮度温度: (9) 当月壤厚度和月表温度分别在0.5m~30m和100K~400K之间变化时,上述四个频率的亮度温度变化范围分别在212.5K~252.8K、207.4 K~266.7K、193.8 K~288.6K和174.0 K~310.9K之间。对于较低频率的被动微波遥感,亮度温度随月壤厚度的增大逐渐增大并趋于稳定;对较高频率的被动微波遥感,亮度温度随月壤厚度的增大会产生起伏波动,不利于用单波段反演月壤厚度。亮度温度梯度在频率较高时梯度较大,在很小的月壤厚度范围内很快就趋于0,不利于厚度较大时的月壤厚度反演,但对于厚度较小时的月壤厚度反演精度较高;同时,除3.0GHz外,7.8GHz、19.35GHz和37.0GHz三个频率的亮度温度梯度随月表温度的升高降幅较大,尤其是19.35GHz,适合在夜间对月壤厚度较小的地区进行更精确的探测。对于3.0GHz,其亮度温度梯度受月表温度变化的影响很小,能反映出较深层月壤厚度的信息,可以对月球进行全球全天时探测。若辐射计的分辨率为0.02K,3.0GHz频率对10m厚月壤的判别精度达到0.07m;对于20m厚月壤的精度为1.4m。当月壤厚度小于0.5m时,随着月壤厚度从0到0.5m增加,月球表层的亮度温度贡献呈先减小后增大的趋势,从而使某一亮度温度值可能对应存在两种不同的月壤厚度。因此,对于月壤厚度小于0.5m的区域,利用单波段被动微波遥感亮度温度反演月壤厚度是比较困难的。 在对月被动微波遥感探测中,可以利用月球夜晚时段的亮度温度数据判别月壤厚度是否小于0.5m。当月表温度为100K时,3.0GHz、7.8GHz、19.35GHz和37.0GHz四个频率的亮度温度判别参考值分别为212.9K、207.4K、193.5K和174.1K;月表温度为240K时,上述四个频率的亮度温度判别参考值分别为220.8K、226.8K、234.1K和237.2K。当亮度温度小于参考值时表示月壤厚度小于0.5m,反之,表示月壤厚度大于0.5m。更进一步地,可以根据月表温度的影响系数对月岩是否裸露于月表进行判断。当3.0GHz、7.8GHz、19.35GHz和37.0GHz四个频率的月表温度影响系数接近0.77、0.82、0.84和0.85时,可以认为月岩直接暴露于月表。
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气溶胶对气候和人类的健康都有重要影响。因此,研究大气总悬浮颗粒物(TSP)的化学组成和物理特性对更深入地了解气溶胶对气候和人类健康的影响具有重要意义。贵阳是中国受燃煤污染比较严重的城市之一,大气中高含量的SO2是其最明显的特征。尽管最近几年空气质量有所改善,但是该区的大气污染问题还比较严重,空气质量仍然不容乐观。我们于2005年1月1日到2005年12月31日在中科院地球化学研究所内全年采集总悬浮颗粒物(TSP)样品,分析测试了其主要无机离子(F-、Cl-、SO42-、NO3-、NH4+、K+、Na+、Ca2+和Mg2+)的化学性质,并结合当地的气象参数(温度,风速,降雨量和相对湿度)系统地研究了TSP及其水溶性无机离子的季节变化特征。本论文的主要结论有: 1. TSP的浓度变化范围为36.91~313.44µg/m3,年均值106.60µg/m3;各离子摩尔浓度的大小顺序为:SO42-> NH4+> Ca2+ > NO3-> K+ > Na+ > Cl- > Mg2+ > F-;SO42- (23.04±12.16µg/m3)和NH4+(3.05±2.23µg/m3)是最主要的离子,分别占总离子摩尔数的37%和30%。TSP及其组分都有明显的季节变化,TSP、Cl-、SO42-、NO3-、NH4+、K+、Na+、Ca2+和Mg2+浓度的冬/夏比值分别为:1.29、5.23、1.35、2.37、1.73、1.22、1.84、1.23和1.02。 2. 温度对TSP及其水溶性无机组分的影响呈现一定的季节变化模式,冬天随温度的升高TSP及其水溶无机组分的浓度也升高,夏天随温度的升高TSP及其水溶性无机组分的浓度降低。但是从全年来看,温度与TSP及其水溶性无机组分之间有弱的负相关性,即随温度的升高,TSP及其水溶性无机组分的浓度有不同程度的下降。相对湿度与TSP及其水溶性无机组分之间存在明显的负相关关系,即随大气相对湿度的增加,TSP及其水溶性无机组分的浓度下降。在相对湿度与TSP及其水溶性无机组分浓度的日变化图中表现为相对湿度的波谷与TSP及其水溶无机组分的浓度的波峰相对应。风速与TSP及其水溶无机组分的浓度之间呈现弱的负相关性。在贵阳,风速对TSP及其水溶无机组分的影响主要表现为扩散作用和稀释作用,由风速导致的尘土再悬浮作用并不明显。雨量对TSP及其水溶性无机组分的影响主要是湿清除作用,具体表现为无雨天TSP及其水溶性无机组分的浓度较雨天高。影响TSP、Ca2+、Mg2+和F-的主要气象参数是相对湿度(RH)和风速,影响SO42-、NO3-、NH4+和Cl-的主要气象参数是温度。 3. 贵阳大气总悬浮颗粒物(TSP)总体偏酸性,TSP水溶液pH值的年均值为6.27±0.41,与总阴离子与总阳离子的当量比Q的年平均值为0.82一致;TSP中高含量的SO42-是贵阳的TSP显酸性的主要原因。 4. NH4+与SO42-和NO3-的相关系数(R)分别为0.85和0.65,NH4+与SO42-的摩尔比值为0.8,说明贵阳TSP中的NH4+主要以(NH4)2SO4的形式存在。Ca2+和Mg2+有较好的相关性(R=0.72)和相似的变化特征,说明二者可能有共同的来源。 5. 2005年贵阳TSP中SO42-/ Ca2+的平均值为13.64,几乎是干净大陆SO42-/ Ca2+的本底值的20倍,说明贵阳的大气污染主要是人为因素所致。NO3-/SO42-的平均值为0.15,说明固定源对贵阳气溶胶的贡献比移动源(通常指交通工具所排放的尾气)对气溶胶的贡献大;
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上芒岗金矿床位于三江褶皱系怒江大断裂西南段,龙陵~瑞丽大断裂(F_1)南东盘,上芒岗次级断裂(F_4)之中。赋矿地层为下二叠统沙子坡组(P_(1s))和中侏罗统勐嘎组(J_(2m))。矿石主要有两种类型,硅质矿石和粘土质矿石;前者主要由石英和少量黄铁矿所组成,金品位平均为2 * 10~(-6);后者主要由伊利石、高岭石和黄铁矿所组成,金品位一般为2 * 10~(-6) ~ 4 * 10~(-6)。矿石中金星次显微状态,主要元素组合为Au、Ag、As、Sb、Hg、Ba。矿床以强烈的黄铁粘土岩化为特征,热液蚀变作用过程即是金矿化作用过程。根据热液蚀变的矿物共生组合及其生成序次,将金矿化作用过程分为五个阶段:黄铁矿-石英阶段(I);镁贝得-白云石阶段(II);辉锑矿-石英阶段(IlI):黄铁矿-高岭石-伊利石阶段(IV);网脉状石英阶段(V)。其中黄铁矿-高岭石-伊利石阶段(IV)是金矿化的主成矿阶段。该矿床属于卡林型金矿床。由石英流体包裹体获得不同成矿阶段的温度为,成矿阶段I:210~170 ℃、成矿阶段III:190~160 ℃、成矿阶段V:173~144 ℃。伊利石-水氢同位素温度计测得成矿阶段IV的温度为165 ℃。石英流体包裹体液相成分以K~+、Na~+和Cl~- (F~-)为主,其次为Ca~(2+)、Mg~(2+)和HC0_3~-,由早到晚K~+、Na~+和Cl~-降低,而Ca~(2+)、Mg~(2+)和HC0_3~-升高;气相组分以C0_2为主。石英流体包裹体成分富F,其含量高达8.03 * 10~(-3) mol/kg,正是由于成矿热液富含F,Al才可以与F形成络合物进入热液迁移,即Al成为活动组份,从而形成该矿床所独特的强烈粘土岩化蚀变。稀土元素特征方面,矿石和赋矿地层下二叠统沙子坡以及中侏罗统勐嘎组岩石的稀土配分曲线十分相似,均为右倾型,但是两者的稀土元素总量不同,前者的相对较高。矿石和蚀变岩具有相似的稀土元素配分曲线,但是矿石的稀土元素总量相对较高。与勐嘎组泥岩相比,粘土质蚀变岩和矿石更加富集轻稀土元素,并且更富Eu。这些特征表明,粘土质蚀变岩和矿石是由热液作用形成的,而不是风化作用的产物;矿石与赋矿地层在物质来源上有亲缘关系。不同矿段、不同阶段和不同类型矿石和蚀变岩的Au、Ag、As以及Sb的含量同步变化,这表明在整个成矿作用过程中,成矿流体来源统一,且在成矿体系起主导作用。不同类型的矿石及蚀变岩中Au与Al_20_3,和TFe的含量呈正相关,表明黄铁粘土岩化与成矿关系最为密切。矿石铅同位素~(208)Pb/~(204)Pb、~(207)Pb/~(204)Pb和~(206)Pb/~(204)Pb比值分别为39.12~39.54、15.85~15.95、19.75~20.33;沙子坡组(P_(1s))岩石铅同位素比值分别为:38.407~37.868、15.921~15.589、22.685~22.367;孟嘎组(J_(2m))岩石铅同位素比值分别为:39.499~39.222,15.821~15.772、19.207~18.709。在铅同位素组成相关图中矿石与地层铅的投影点分别集中成群分布。矿石铅与地层铅呈线性分布,而且矿石铅的集中区位于沙子坡组铅集中区和勐嘎组铅集中区之间。这些特征表明矿石铅系由沙子坡组铅和勐嘎组铅混合而成。成矿热液的δ~(18)O由早到晚逐渐升高,I、III、IV、V阶段流体的δ~(18)O值分别为-4.2‰,+0.59‰;+0.76‰,+1.98‰,表现出明显的漂移特征;而δD则表现出高度的一致性,变化范围为-82.5 ~ 79.48‰。由此认为成矿热液系大气降水起源。成矿热液氢、氧同位素组成的这种规律性变化还说明,成矿热液的演化具有继承性和连续性。应用CHILLERR软件包,对上芒岗金矿床的成矿作用过程进行化学反应途径数字模拟。所展示的成矿作用过程为:大气降水沿断裂带下渗,加热循环,获取成矿物质(但不排除有深源成矿物质加入的可能性);形成起始成矿热液:T = 200℃ P = 228.8bar;pH = 4.4;fs_2 = 10~(-9.89); fo_2 = 10~(-41.28);aAu(HS)_2~- = 10~(-9.64),aAuCl_2~- = 10~(-17.86);富含F、Al和Au,贫As、Hg、Zn、Cu和Pb。成矿热液在构造作用的驱动下,上升进入上芒岗断裂上部含水构造破碎带,并与下渗雨水混合而淬冷,形成沿上芒岗断裂呈线状分布的早期硅化石英岩(成矿阶段I),成矿热液与下渗雨水之比为16:l(成矿阶段I);继而热液扩散进入下盘破碎带,与白云岩反应,形成矿体下盘的白云石化,水:岩比为193:l(成矿阶段II)。此后成矿热液上升充填裂隙空间,由于热传导而缓慢冷却,成矿体系的温度由189 ℃降为165 ℃,形成含辉锑矿的梳状石英脉(成矿阶段1II)。成矿热液继续上升进入上盘碎屑岩破碎带,停积于构造揉皱的泥质岩,并与之反应,形成上芒岗矿床金矿化的主体—粘占土质矿石,水:岩比为29:1(成矿阶段IV)。最后成矿残液逐渐冷却, 同时伴随C0_2的起泡,形成晚期石英网脉(成矿阶段V),至此热液金矿化过程结束。由上述可见上芒岗金矿床的成矿作用过程经历了:(初始)成矿热液与下渗大气降水混合(I) → 成矿热液与沙子坡组白云岩反应(II) → 成矿热液缓慢冷却(III) → 成矿热液与勐嘎组泥质岩石反应(IV) → 成矿热液冷却沸腾(V)等5个演化阶段。模拟结果进一步证实了上芒岗金矿床的热液成因。上芒岗金矿床成作用过程化学反应途径数字模拟与地质事实高度吻合,与地球化学研究结果相互印证,再现了上芒岗金矿床的成矿作用过程。由矿床的地质地球化学特征及成矿作用过程化学反应途径模拟结果,归纳出上芒岗金矿床成矿作用过程模型。
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O presente trabalho foi elaborado a fim de que os usuários que utilizam o Sistema Bife de Qualidade pudessem consultar um manual de uso das ferramentas do sistema sempre que tivessem dúvidas em relação ao uso do mesmo. A vantagem de um manual de uso é que se consegue explicitar as principais funcionalidades do sistema sem exibir, no entanto, um texto abrangente e cansativo de ser lido. As diversas informações obtidas durante o desenvolvimento do sistema, tais como as coletadas em entrevistas com os principais usuários do sistema, foram consideradas na elaboração deste trabalho. Sendo assim, o objetivo do manual é reunir, de forma clara e objetiva, todas as funcionalidades fornecidas pelo Sistema Bife de Qualidade, de tal modo que os usuários possam encontrar instruções para interagir facilmente com cada uma das funcionalidades apresentadas.
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In this reported clinical case, a healthy and well-trained male subject [aged 37 years, maximal oxygen uptake (V[Combining Dot Above]O2max) 64 mL·kg·min] ran for 23 hours and 35 minutes covering 160 km (6.7 km/h average running speed). The analysis of hematological and biochemical parameters 3 days before the event, just after termination of exercise, and after 24 and 48 hours of recovery revealed important changes on muscle and liver function, and hemolysis. The analysis of urine sediments showed an increment of red and white blood cells filtrations, compatible with transient nephritis. After 48 hours, most of these alterations were recovered. Physicians and health professionals who monitor such athletic events should be aware that these athletes could exhibit transient symptoms compatible with severe pathologies and diseases, although the genesis of these blood and urinary abnormalities are attributable to transient physiological adaptations rather to pathological status.