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121.
混合型尿路结石的XPS和XRD联合分析 总被引:6,自引:0,他引:6
欧阳健明 《光谱学与光谱分析》2003,23(2):391-395
为了深入了解广东省珠江三角洲尿路结石的组份,为临床的相关研究和预防提供参考,采用X-射线光电子能谱(XPS)和X-射线衍射法(XRD)对6例典型的混合型尿路结石成份和物相进行了分析。结果表明,所检尿石成份合一水草酸钙、二水草酸钙、羟基磷灰石,其中2例含有少量磷酸铵镁。随着尿石中磷酸盐的增加,一水草酸钙(COM)的含量减少,二水草酸钙(COD)含量增加,表明磷酸盐的沉积抑制了高能量的COD向低能量的COM转化。采用XPS和XRD联合分析,可以较为准确地检测尿路结石的组份和物相。 相似文献
122.
Gloria Vaggelli Filippo Olmi Mirko Massi Lorenzo Giuntini Mariaelena Fedi Laura Fiora Roberto Cossio Alessandro Borghi 《Mikrochimica acta》2004,145(1-4):249-254
The economic interest in natural stones provides an interesting input to the study of coloured rock-forming minerals. Generally, the colour of a mineral is attributed either to the presence of intrinsically-coloured constituents or of trace elements substituting major elements in the crystallographic sites, or to physical factors such as crystal lattice defects. We have analysed the blue and blue-green silicate minerals dumortierite and amazonite, coming from Mozambique quartzites, and from Malawi and Brazil granitoids, respectively. This study was performed by a multiple analytical approach including (a) a comparison of different signals (optical light-polarized images, backscattered electron images and X-ray multielemental maps); and (b) a collection of quantitative data obtained by WDS systems for major elements, and by WDS and/or micro-PIXE facility for trace elements. A good correlation between Ti concentration zoning and pleochroism variations was observed in dumortierite. In addition, the blue dumortierite of Mozambique, with its unusual significant amounts of antimony (about 5 wt.% Sb2O3), represents a mineral with an intermediate composition between dumortierite and holtite. In amazonite the aquamarine colour seems to be related to the Pb content on the order of some hundreds of ppm. 相似文献
123.
Laura Short Alston V. Thoms Bin Cao Alexander M. Sinyukov Amitabh Joshi Rob Scully Virgil Sanders Dmitri V. Voronine 《Journal of Raman spectroscopy : JRS》2015,46(1):126-132
We performed food residue analysis of fire‐cracked rock (FCR) from experimental and prehistoric earth ovens using a handheld Raman spectrometry. Progress in modern optical technology provides a facile means of rapid non‐destructive identification of residue artifacts from archaeological sites. For this study spectral signatures were obtained on sotol (Dasylirion spp.) experimentally baked in an earth oven as well as sotol residue on an experimentally used processing tool. Inulin was a major residue component. The portable handheld Raman spectrometer also detected traces of inulin on experimental boiling stones used to boil commercially obtained inulin. The Raman spectra of inulin and sotol may be useful as signatures of some wild plant residues in archaeology. Spectroscopic analysis of millennia‐old FCR from prehistoric archaeological sites in Fort Hood, TX revealed the presence of residues whose further identification requires improvement of current optical methods. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
124.
Constituents of urinary stones obtained from various patients from western part of India, which is a highly urinary stone
disease-prone area, have been analysed. Eight stones from four patients were collected through urologists and have been analysed
using powder X-ray diffraction and FT-IR. Thermogravimetric analysis (TGA) and scanning electron microscopic (SEM) image of
selected samples were also carried out. The analysis revealed that calcium oxalate monohydrate, which is also known as whewellite,
is the common constituent of all of the stones, particularly at the initial stage of stone formation. However, multi phases
viz. whewellite phase, and hydroxyl and carbonate apatite phases are also detected in the case of third and fourth patients,
from where multiple stones were obtained. Interestingly, in these mixed phase stones the concentration of whewellite decreases
with increasing the concentration of apatite phases. Thermal behaviour of the whewellite phase was studied by TGA and variable
temperature XRD analysis. Morphology of the whewellite and apatite phases, examined by SEM image, has also been reported. 相似文献
125.
M. Mályusz A. Klötzing M. Lange T. Mályusz A. Hackl P. Wrigge 《Isotopes in environmental and health studies》2013,49(2-3):123-132
Hippurate, synthetized from benzoate and glycine in the liver and in the kidney of several species modulates the activity of renal γ-glutamyl-transpeptidase. By this mechanism hippurate interferes with renal intra-luminal ammonia production. Besides, in the rat hippurate serves as a minor substrate for renal ammoniagenesis as well. Hippurate may yield ammonia from its glycine moiety either after cleavage by hippuricase, or after condensation with an aldehyde according to Erlenmeyer's reaction. This reaction results in producing equimolar amounts of ammonia, benzoate and an α-keto acid, thus in a net gain of an acid equivalent. -In order to evaluate variability and extent of renal ammonia production from hippurate in different species, experiments were carried out on isolated tubular segments of the rat and on cortical kidney slices of rat, cow, man and cat. The incubation medium was enriched with J0mmol/1 hippurate spiked with 5% of 15N-hippurate, some of the known inhibitors of hippuricase and γGT as well as glyceraldehyde or propional-dehyde. Factors known to affect hippuricase or γGT did not interfere with renal ammonia production from hippurate, but glyceraldehyde and propionaldehyde (up to 1mmol/1) had a stimulating effect. Renal ammoniagenesis from hippurate as well as production of benzoate was lowest in the cow (~ 0.1%), amounted to 1–2% in rat and man and reached high values in the cat (up to 15% of the total ammonia production). These results indicate that hippurate could have physiological significance in the renal metabolism of some species. 相似文献
126.
Preparation and ozone-surface modification of activated carbon. Thermal stability of oxygen surface groups 总被引:1,自引:0,他引:1
The control of the surface chemistry of activated carbon by ozone and heat treatment is investigated. Using cherry stones, activated carbons were prepared by carbonization at 900 °C and activation in CO2 or steam at 850 °C. The obtained products were ozone-treated at room temperature. After their thermogravimetric analysis, the samples were heat-treated to 300, 500, 700 or 900 °C. The textural characterization was carried out by N2 adsorption at 77 K, mercury porosimetry, and density measurements. The surface analysis was performed by the Bohem method and pH of the point of zero charge (pHpzc). It has been found that the treatment of activated carbon with ozone combined with heat treatment enables one to control the acidic-basic character and strength of the carbon surface. Whereas the treatment with ozone yields acidic carbons, carbon dioxide and steam activations of the carbonized product and the heat treatment of the ozone-treated products result in basic carbons; the strength of a base which increases with the increasing heat treatment temperature. pHpzc ranges between 3.6 and 10.3. 相似文献
127.
Pooled livers and pooled kidneys from rats or mice were homogenized and spiked with arsenite or arsenate in the concentration range 1.3–20 μmol dm?3. Methylarsenic and dimethylarsenic compounds were determined by the hydride generation technique in the homogenates after a 90 min incubation at 37°C. The rat homogenates methylated arsenite and arsenate more efficiently than the mouse homogenates. Monomethylated arsenic was present in larger amounts than dimethylated arsenic in the rat homogenates. In the absence of reduced glutathione (GSH), no methylation occurred. Addition of GSH promoted monomethylation and dimethylation, whereas dithiothreitol and mercaptoethanol (10 mmol dm?3) fostered only monomethylation. The amounts of monomethylated arsenic in the rat liver homogenates increased with increasing arsenite concentration (1.3–20 μmol dm?3) however, the percentage of arsenic that had been methylated decreased. A similar trend, but with much less monomethylarsenic formed, was observed for arsenate-spiked homogenates. Rat kidney homogenates methylated arsenite and arsenate to a much smaller extent than rat liver homogenates. The Km values for the monomethylation in rat liver homogenates were found to be 5.3 μmol dm?3 for arsenite and 59 μmol dm?3 for arsenate. 相似文献
128.
目的分析在慢性肾脏病3~4期肾性贫血患者治疗中,双倍剂量生血宁片的临床应用疗效。方法选取江西省九江市中医院于2014年2月至2015年2月收治的62例慢性肾脏病3~4期肾性贫血患者为研究对象,将其随机分为对照组与观察组,对照组患者服用常规剂量的生血宁片接受治疗,观察组患者则在对照组患者基础上服用双倍剂量生血宁片,对比两组患者的临床治疗效果及Hb、SF、TAST等指标情况。结果观察组患者的临床治疗效果明显好于对照组,主要生理指标改善情况也比对照组患者更为明显,两组患者数据经对比后差异具有统计学意义(P0.05)。结论在慢性肾脏病3~4期肾性贫血患者的治疗中,双倍剂量生血宁片的应用效果较好,值得推广应用。 相似文献
129.
为寻找镍(Ni)新型解毒剂,小鼠腹腔注射氯化镍溶液(5 mg Ni/kg),观察二乙氨基二硫代甲酸钠(DDTC),二羟乙氨基二硫代甲酸钠(DHED),N-苯甲基-D-葡糖氨基二硫代甲酸钠(BGD),meso-2,3-二巯基丁二酸钠(DMSA)及环己烷二胺四乙酸钠(CDTA)等螯合剂对镍致小鼠肾脏毒性的解毒作用。镍染毒引起小鼠肾脏脂质过氧化(LPO)和钙、铁及锌浓度增加,血清肌酐及血液尿素氮(BUN)升高。镍染毒30分钟和24小时后进行各螯合剂治疗(剂量均为400 μmol/kg 相似文献
130.
This work aims to assess the adsorption efficiency of date stones biowaste subjected to carbonization and activation processes for the removal of Pb ions from single and mixed solutions. Several techniques have been used for characterization of adsorbents such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), methylene blue index and point of zero charge (pHpzc). An excellent adsorption capacity of 97.43% is achieved at an initial concentration of 300 ?mg/L, solution volume 75 ?mL of Pb nitrate, adsorbent mass of 0.7 ?g, temperature of 30 ?°C, a stirring speed of 500 ?rpm/min, a contact time of 180 ?min and pH 6. Specifically, a comparison has been conducted between carbonized/activated date stones “CADS” and commercial activated carbon “CAC” besides investigating the influence of the presence of Co ions and the utilization of ultrasound radiation. A higher adsorption rate of 98.16% is reached under ultrasound radiation at Pb(II) initial concentration of 100 ?mg/L for a contact time of 3 ?h. Nevertheless, the temperature has shown a negative effect; the adsorption rate decreases from 98.31% at 18 ?°C to 92.70% at 60 ?°C. The modeling of the experimental adsorption data manifests a type-L isotherm characteristic of Langmuir and Freundlich models. The kinetic study has shown that the experimental data are well described by a pseudo-second-order rate model and controlled by the internal diffusion, a limiting-step that controls the transfer rate of Pb(II) to the adsorbent surface. The calculated thermodynamic parameters (ΔG0, ΔH0, ΔS0) indicate that the adsorption of Pb(II) is spontaneous and exothermic process. 相似文献