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1.
The quality variety wines which are produced in specified regions of Slovakia are mostly watched category of wine in European Union. Quality of the measurement for appropriate parameter in wine sample is given by uncertainty. Therefore, protocol of analysis has to have an uncertainty of measurement and should be made in accredited laboratory. In Slovakia, there are six wine growing regions (Tokaj, east Slovakia region, south Slovakia region, middle Slovakia region, Nitriansky region and Little-Carpathian region) where the quality wines with protected designation of origin are produced. Central Controlling and Testing Institute in Agriculture in Bratislava is a state organization, which has an accredited laboratory for testing wine products before introduction into the market. This article presents the results of the authors' measurements in proficiency testing FAPAS (food analysis performance assessment scheme) which were organized by Central Science Laboratory in York (England) in 2011. The authors add also interlaboratory comparison in 2012 between Slovak accredited laboratories. The results show very good agreement. Quality control in the wine sector presents very important feature in the market, therefore, using certified reference materials and checking the accredited laboratories with interlaboratory comparisons is very helpful. Testing of wine in the authors' laboratory is performed by EN ISO/IEC: 17025. The results show that z-score lies not outside the range ±2 and this is a chance that the authors' results are actually acceptable.  相似文献   

2.
The occurrence of interbeds in thick oil formations is one of the main reasons that cause the difference of remaining oil distribution. A quantitative method for predicting interbeds was proposed and the sedimentary origin and division criterion were demonstrated. The distribution of interbeds in different types of sedimentary sand bodies were predicted and analyzed by combining the theory of sedimentology and reservoir bed architectural-element analysis. The interbeds in a single well were recognized from high resolution well logs, and inter-well interbeds were predicted by using the methods of cyclothem correlation, physical properties truncation, and conditional simulation. Finally a 3-D model of interbed was built. Application to the Gudao Oilfield was successful.  相似文献   

3.
With permanent down-hole gauges (PDGs) widely installed in oilfields around the world in recent years, a continuous stream of transient pressure data in real time is now available, which motivates a new round of research interests in further developing pressure transient processing and analysis techniques. Transient pressure measurements from PDG are characterized by long term and high volume data. These data are recorded under unconstrained circumstances, so effects due to noise, rate fluctuation and interference from other wells cannot be avoided. These effects make the measured pressure trends decline or rise and then obscure or distort the actual flow behavior, which makes subsequent analysis difficult. In this paper, the problems encountered in analysis of PDG transient pressure are investigated. A newly developed workflow for processing and analyzing PDG transient pressure data is proposed. Numerical well testing synthetic studies are performed to demonstrate these procedures. The results prove that this new technique works well and the potential for practical application looks very promising.  相似文献   

4.
The origin of the unusually high dibenzothiophene (DBT) concentrations in Lower Ordovician oils from the Tazhong Uplift,Tarim Basin was studied by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS).The most abundant sulfur compounds in the oils are S 1 species with doublebond equivalent (DBE) values of 1-19 and 11-48 carbon atoms.The range of the number of carbon atoms in the sulfur compounds detected by the FT-ICR MS (S 1 species with DBE=9) is about ten times larger than that for sulfur compounds detected by GC/MS (DBTs).This suggests that FT-ICR MS is a much better approach than GC/MS for characterization of DBTs in crude oils.The abundance of S 1 species with DBE=1-8 decreased with increasing thermal maturity,while the abundance of S 1 species with DBE=9 (primarily DBTs) increased.Therefore,thermal maturity is an important factor in the formation of oils with high DBT concentrations.Unusually high abundances of S 1 species with low DBE values (1-8),which include sulfide,thiophene and benzothiophene,were observed in several oils,especially the TZ83 (O 1) oil with high or very high thermal maturity.Thermochemical sulfate reduction (TSR) was thought to be the reason for the high abundance of these low DBE compounds in deep reservoirs,and thermochemical sulfate reduction could affect the distribution and composition of DBTs in the oils.According to the results of FT-ICR MS analysis,there are no signs that TSR is occurring or has occurred recently for most of the Lower Ordovician oils.  相似文献   

5.
Phytoremediation of petroleum polluted soil   总被引:1,自引:0,他引:1  
An experimental study of the rhizosphere effect on phytoremediation of petroleum polluted soil was carried out with three species of grasses, namely Pannicum, Eleusine indica (L.) Gaerth, and Tall Fescue. After a period of 150 days, this pot experiment showed that the rhizosphere of these three species accelerated the degradation of petroleum hydrocarbons to different extents. The results showed that the number of microorganisms in the rhizosphere increased by three orders of magnitude. The induction of the plant rhizosphere and the coercion influence of petroleum changed the species and activity of microorganisms. The degradation of petroleum hydrocarbons in the rhizosphere was 3-4 times that in unplanted soil. The dehydrogenase activity in the rhizosphere was 1.61-2.20 times that in unplanted soil, but the catalase activity was 0.90-0.93 times that in unplanted soil, and soil moisture content increased by 5% compared with the unplanted soil.  相似文献   

6.
The authors examined the thermal change in the aroma profile of myrrh. The fresh odor of raw myrrh and its hexane extract depended on the amount of (E)-13-ocimene. Myrrh was extracted with hexane to avoid inducing changes in the constituents and odor. The main constituent, (E)-L3-ocimene (group A; low boiling point), and the other constituents (group B; high boiling point) of the hexane extract were separated by bulb-to-bulb distillation. The constituents of groups A and B were analyzed over time by nuclear magnetic resonance analysis and the odors were evaluated. Myrrh's odor depended on both the amount of thermally unstable (E)-[3-ocimene, which contributed to the fresh odor, and the constituents of group B (thermally stable), which contributed to the myrrh-like odor. Six compounds (c~-santalene, (Z)-a-bisabolene, c~-bergamotene, (E)-ct-santalal, c~-photosantalol and campherenol) were isolated from group B. No individual group B component had a myrrh-like odor, although the combined odor of group B was myrrh like. The authors demonstrated that the aroma profile of myrrh depends on the thermal instability of (E)-~-ocimene and a combination of six thermally stable terpenes with similar molecular structures.  相似文献   

7.
A new type of boron - nitrogen modified fatty acid as water base lube additive was prepared and the chemical structure characterized by infrared spectrum. The tribological properties of the additive in water were evaluated by friction testers. The morphographies and tribochemical species of the worn surfaces were analyzed by means of X - ray Photoelectron Spectroscope (XPS).The results showed that the additive is excellent in increasing load - carrying capacity, anti - wear and friction - reducing abilities of water. The lubrication mechanism is inferred that a high strength adsorption film and a tribochemical reaction film are formed on the rubbing surfaces due to the carder effect of the long chain fatty acid molecules, high reaction activities of nitrogen, electron - deficient orbit of boron and their synergisms.  相似文献   

8.
Oils of AD (Adansonia digitata), AL (Albizia lebbeck) and DO (Daniellia oliveri) were studied using ^13C NMR (nuclear magnetic resonance) and ^1H NMR. The gated decoupled high resolution ^13C NMR spectra revealed the presence of both saturated and unsaturated triacylglycerides. However, there is a higher percentage of unsaturation in AL seed oil. The peaks at 0.7 ppm to 0.9 ppm which correspond to the terminal methyl groups in the fatty acid and that at 1.2 ppm to 1.3 ppm are more intense and bigger in DO which show that it is more saturated than AD and AL oils. The results obtained by ^13C NMR and ^1H NMR are compared favorably with those obtained by gas chromatographic analysis.  相似文献   

9.
Better well logging techniques for geologic investigations are urgently needed to identify and evaluate complex reservoirs.We describe a new type of 3D transmitter station with corresponding circuits and bodies.They can be used in a promising new technique of acoustic reflection well logging,that features better azimuthal detection capabilities,as well as better investigation depth.The transmitter stations consist of three-level subarrays that can radiate acoustic energy in any required azimuth of 3D space by circularly exciting various combinations at different levels.We tested the 3D acoustic transmitter stations and obtained laboratory directivity measurements with the3 D acoustic transmitter stations for the first time.The results show that the 3-d B beam width in the horizontal plane ranges from 59° to 67° as a result of phase-delayed excitation.The main beam is steered in the vertical plane at a deflection angle that ranges from 0° to 16° when the delay time of the excitation pulse between each pair of adjacent arc arrays is gradually adjusted.The 3-d B beam width is equal to 11°,whereas the deflection angle in the vertical plane is equal to 14°.Each of the four third-level subarrays in the same circumferential direction display consistent horizontal and vertical directivities,thus satisfying the requirements of azimuthal acoustic reflection logging.  相似文献   

10.
In this study, the main factors influencing the measurements by means of the off-line low-field ^1H NMR in the lab were discussed base on a robust calibration model established by the PLS algorithm using 255 crude oil samples. The preheating temperature had a great influence on the viscosity of oil samples and the resolution of spectral analysis. The repeatability of spectral measurements was impacted by the metal and wax content of the oil samples. For the case of high wax content oils, the wax species began to crystallize in the course of determination that could affect the repeatability of spectral measurements. These Factors have evidenced why the preheating devices and filter unit are necessary when low field NMR system is used in the online analysis process. The investigation is very important for the on-line application of the low field NMR.  相似文献   

11.
In order to analyze and compare the differences in pore structures between shale gas and shale oil formations, a few samples from the Longmaxi and Bakken Formations were collected and studied using X-ray diffraction, LECO TOC measurement, gas adsorption and field-emission scanning electron microscope. The results show that samples from the Bakken Formation have a higher TOC than those from the Longmaxi Formation. The Longmaxi Formation has higher micropore volume and larger micropore surface area and exhibited a smaller average distribution of microsize pores compared to the Bakken Formation. Both formations have similar meso-macropore volume. The Longmaxi Formation has a much larger meso-macropore surface area, which is corresponding to a smaller average meso-macropore size. CO_2 adsorption data processing shows that the pore size of the majority of the micropores in the samples from the Longmaxi Formation is less than 1 nm, while the pore size of the most of the micropores in the samples from the Bakken Formation is larger than 1 nm. Both formations have the same number of pore clusters in the 2–20 nm range, but the Bakken Formation has two additional pore size groups with mean pore size diameters larger than 20 nm. Multifractal analysis of pore size distribution curves that was derived from gas adsorption indicates that the samples from the Longmaxi Formation have more significant micropore heterogeneity and less meso-macropore heterogeneity. Abundant micropores as well as mesomacropores exist in the organic matter in the Longmaxi Formation, while the organic matter of the Bakken Formation hosts mainly micropores.  相似文献   

12.
29Si-NMR and 1H-NMR were used to follow up the basic hydrolysis of tetraethyl orthosilicate (TOES) and the results showed that species of monomer, dimer, trimer, cyclic and polymer silicates were formed. The monomer and dimer were favorable for the high activity of zeolite. XRD, 13C CP/MAS and 29Si NMR were used to trace the crystallization process of hollow titanium silicalite zeolites (HTS). The results showed that the induction period of HTS was 80 min, and subsequently it took next 10 min to form HTS and the remaining time of the crystallization period might function for cleaning up the pores and/or washing off the impurities from the HTS zeolite. The catalytic oxidation performance of HTS zeolite is different from that of the acid activity of zeolite in which the conventional definition of crystallinity does not reflect the catalytic oxidation activity proportionally. The synthesized HTS samples were character- ized by XRD, FT-IR, UV-Vis and Raman spectra. It was confirmed that Ti was incorporated into the zeolite framework. The synthesized HTS samples revealed good repeatability and high activity for oxidation of phenol into diphenol.  相似文献   

13.
The study of the chlorite coatings always attracts scholars in China and other countries because the chlorite coatings play an important role in the preservation of residual primary pores in sandstone reservoirs.At present,the study of the origin and the controlling factors is relatively few.The occurrence,time of formation,genesis,controlling factors,and the mechanism of chlorite coatings inhibiting quartz overgrowths were studied in detail with thin section and SEM analysis.Samples were from the sandstone reservoirs of the T3x Group in the Baojie area,the transitional zone from the middle to the south of Sichuan Basin.The results indicate that the chlorite coatings on the walls of the pore spaces are oriented perpendicular to grain surfaces in the form of isopachous(even-thickness) grain-coating,while the chlorite coatings at the contacts between adjacent detrital grains are arranged with a preferred orientation tangential to the surface of detrital grains.The chlorite coatings were formed in the eogenetic stage.They were formed by recrystallization of Fe-rich clay films during the syndepositional period,and chlorite cements would be recrystallized after the coatings’ formation.The formation of chlorite coatings was mainly controlled by the depositional environment,provenance conditions,and diagenetic environment.The presence of chlorite coatings could result in the preservation of primary pores in deeply buried sandstone reservoirs by effectively inhibiting quartz overgrowths and the development of compaction and pressure solution.  相似文献   

14.
Compressor station personnel: The compressor station is the ‘heart' of the natural gas pipeline; there are 11 compressor stations along the over 1800 km of C line that makes up the Central Asia natural gas pipeline. Only by continually providing power at compressor stations can clean natural gas from Central Asia be transported to inland China.  相似文献   

15.
Different imines were prepared.The reaction was carried out using different conditions,with aromatic aldehydes,aniline and with different energy sources.Yield,purity and experimental fusion point were calculated in each case,and they were compared to the ones found in literature.The importance of structural effects of aldehyde reacting with aniline was established as well as reaction conditions.The efficacy of the reaction can not be predicted,since each aldehyde has a different structure and therefore reacts differently.The main objective of this project is academic.A methodology to carry out a structured research(it is one of the levels of problem-based learning(ABP)),was implemented.Students work in pairs using Combinatorial Chemistry,and each pair does a different exercise on the same theoretical objective.Results from every team are discussed in a seminary where conclusions regarding which was the most efficient reaction are reached.  相似文献   

16.
Wellbore drilling operations frequently entail the combination of a wide range of variables. This is underpinned by the numerous factors that must be considered in order to ensure safety and productivity. The heterogeneity and sometimes unpredictable behaviour of underground systems increases the sensitivity of drilling activities. Quite often the operating parameters are set to certify effective and efficient working processes. However, failings in the management of drilling and operating conditions sometimes result in catastrophes such as well collapse or fluid loss. This study investigates the hypothesis that optimising drilling parameters, for instance mud pressure, is crucial if the margin of safe operating conditions is to be properly defined. This was conducted via two main stages: first a deterministic analysis—where the operating conditions are predicted by conventional modelling procedures—and then a probabilistic analysis via stochastic simulations—where a window of optimised operation conditions can be obtained. The outcome of additional stochastic analyses can be used to improve results derived from deterministic models. The incorporation of stochastic techniques in the evaluation of wellbore instability indicates that margins of the safe mud weight window are adjustable and can be extended considerably beyond the limits of deterministic predictions. The safe mud window is influenced and hence can also be amended based on the degree of uncertainty and the permissible level of confidence. The refinement of results from deterministic analyses by additional stochastic simulations is vital if a more accurate and reliable representation of safe in situ and operating conditions is to be obtained during wellbore operations.  相似文献   

17.
Effects of nitrogen-contained biodegradation enhancers: methyl diethanolamine oleate (MDEAO) and oleic diethanolamide (ODEA) on the adsorption behavior of n-hexadecane in soil were studied by laboratory batch experiments. The effect of two biodegradation enhancers on the partition coefficient (Kd values) and normalized to organic matter (Koc values) were determined. The adsorption isotherm curve of n-hexadecane in soil-water system were plotted. The measured results demonstrated that Koc values changed in the soil-water system with different enhancers but are relatively invariant for the same site soil. The Kd values rose with the increase of the organic matter content in different soil. The average values of Koc in soil-water system with MDEAO, ODEA and blank soil were 0.412, 0.252 and 0.309, respectively. The critical micelle concentration of ODEA and MDEAO were 0.7 mg/L and 1.9 mg/L, respectively, which means the solubilization capacity of ODEA is much stronger than MDEAO in soil-water system. Consequently, adsorption of MDEAO onto the solid surface increases the organic matter content in soil and makes it more effective in enhancing n-hexadecane adsorption. Oppositely, ODEA inhibits the adsorption of n-hexadecane due to less adsorption onto the soil particle surface and higher concentration in the soil-water system. According to the correlation coefficients, it was found that both Henry linear and Freundlich nonlinear isotherm sorption models were fitted to the data very well but the Freundlich model was better.  相似文献   

18.
It is of paramount importance to improve the utilization efficiency of hollow titanium silicate(HTS) zeolite catalyst used in the cyclohexanone ammoxidation process. To achieve this aim, the regeneration of simulated deactivated HTS zeolite by post-synthesis was carried out in an aqueous TPAOH solution under hydrothermal conditions. It was found that the catalytic performance for phenol hydroxylation over regenerated HTS zeolite was as high as that of fresh one.Judging from the BET measurements, electron micrography and XRD analysis results, it was confirmed that the topological and morphological structure was repaired. The chemical state of Ti species was detected by the UV-Vis and ~(29)Si MAS NMR spectroscopy. No acidic amorphous TiO_2-SiO_2 oxide was formed, and the extraframework Ti species could be reincorporated into the framework of HTS zeolite thanks to the tetrahedral coordination by the condensation between Ti-OH and Si-OH groups. In order to confirm this conclusion, the fresh HTS zeolite was treated under the NH_3·H_2O hydrothermal and thermal conditions for several times. The catalytic activity of both uncalcined and calcined simulated deactivated HTS zeolite samples could be regenerated without the formation of Br?nsted acid sites. It was concluded that the highly dispersed Ti species could be reincorporated into the framework of zeolite by hydrated condensation of Si-OH and Ti-OH groups after secondary hydrothermal synthesis.  相似文献   

19.
Among the different methods used for reducing viscosity of bitumen,acoustic cavitation during sonication is well recognised.Several chemical methods were used to detect the production of reactive species such as hydroxyl radicals and hydrogen peroxide during acoustic cavitation processes.However,quantification of cavitation yield in sonochemical systems is generally limited to low frequencies and has not been applied to bitumen processing.An empirical determination of the cavitation yield in midto high-frequency range(378,574,850,992,and1173 k Hz)was carried out by measuring the amount of iodine liberated from the oxidation of potassium iodide(KI).Further,cavitation yield and the effects of different sonic operating conditions such as power input(16.67%–83.33%)and solute concentration on cavitation yield were carried out in KI solution and sodium carboxymethyl cellulose–water mixture to obtain benchmark changes in rheology and chemistry using these two model fluids.The findings were then applied to bitumen upgrading through sonication.Through this study,it was found that the chemical cavitation yield peaked with a sonication frequency of 574 k Hz.It was also found that cavitation yield and viscosity change were correlated directly in bitumen and a 38%lower bitumen viscosity could be obtained by acoustic cavitation.  相似文献   

20.
The microbial community structure and functionally distinct groups in three kinds of produced water samples from the shallow,mesothermic and low-salinity Daqing oil reservoir were systematically evaluated using both culture-dependent and culture-independent methods.Sequence analysis of the 16S rRNA genes indicated that the bacterial library was dominated by Acinetobacter and Arcobacter and the archaeal community was dominated by Methanosaeta and Methanolinea.Two isolated methanogens were closely related with Methanothermobacter thermautotrophicus and Methanoculleus receptaculi.The fermentative bacteria were identified as Pseudomonas,Haloanaerobium,Alcalibacter,Arcobacter,and Pannonibacter.The predominant nitrate-reducing bacteria fell within the genus Pseudomonas.The dominant members of the cultured hydrocarbon-oxidizing bacteria were phylogenetically associated with Micrococcus,Pseudomonas,and Bacillus.Enrichments of biosurfactants and biopolymer producing groups mainly yielded Pseudomonas,Bacillus,and Acenitobacter-related members.The functional groups related to polymer degradation were also affiliated with Pseudomonas and Bacillus.Results from this study provide the fresh insight into the diversity of microbial communities in Daqing petroleum reservoirs.The vast pool of functional strains retrieved in this study was presumed to include the promising strains that could be applied in microbial-enhanced oil recovery in future.  相似文献   

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