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1.
Classification of seized methamphetamine by impurity profiling can provide very useful information in criminal investigations of drug traffic routes, sources of supply and relationships between seizures. The aim of this study is to improve and develop an analytical method for detecting impurities such as starting materials and by-products in illegally prepared methamphetamine.HCl samples. A 50mg sample of methamphetamine.HCl was dissolved in 1 ml of buffer solution (four parts 0.1M phosphate buffer pH 7.0 and one part 10% Na2CO3). Impurities were extracted with 0.5 ml of ethyl acetate containing four internal standards (ISs) (n-decane, n-pentadecane, n-nonadecane and n-hexacosane) and analyzed by gas chromatography (GC) using a flame ionization detector (FID) on a DB-5 capillary column (0.32 mmi.d. x 30 m, film thickness 1.0 microm). The use of a middle-bore column offered better separation of the impurity peaks. The correction of the retention times of impurity peaks with four ISs made peak identification very accurate for subsequent data processing. Twenty-four characteristic peaks were selected for comparison and similarity and/or dissimilarity between samples, and the data were evaluated by the Euclidean distance of the relative peak areas after logarithmic transformation. The results indicate that the present method would be useful for methamphetamine impurity profiling.  相似文献   
2.
Laser detection of latent fingerprints on a white paper has been performed, previously. Ultraviolet fluorescence from various kinds of printer toner and ink used for home printers were measured to study fluorescence imaging of fingerprints on a color-printed white paper. The experimental system consisted of a nanosecond pulsed tunable laser and a cooled CCD camera. Excitation wavelengths are 230 and 280 nm. Fourteen printers consisting of three color laser printers, three color inkjet printers, five monochrome laser printers, two monochrome copy machines, and a color copy machine were tested. Toner and ink of most printers exhibited fluorescence in the region from 360 to 550 nm. In most cases, clear fluorescence images were obtained by time-resolved imaging with a band-pass filter and 280-nm excitation. However for toners from laser color printers that showed strong fluorescence, better results were obtained with 230-nm excitation. Latent fingerprints on a photograph page and a black-character page of a newspaper were also imaged.  相似文献   
3.
Detection of aged fingerprints is difficult because they can degrade over time with exposure to light, moisture, and temperature. In this study, aging fingerprints were visualized by time‐resolved spectroscopy with an ultraviolet‐pulsed laser. Fingerprints were prepared on glass slides and paper and then stored under three lighting conditions and two humidity conditions for up to a year. The fluorescence intensities of the fingerprints decreased with time. Samples were stored in the dark degraded less than in sunlight or under a fluorescent lamp. Samples were stored under low humidity degraded less than under moderate humidity. As the storage period increased, a fluorescence emission peak appeared that was at a longer wavelength than the peak visible in earlier spectra. This peak was used for visualization of an aged fingerprint over time. An image of the fingerprint was not initially visible, but an image appeared as the time since deposition of the fingerprint increased.  相似文献   
4.
Abstract:  This paper presents results of experiments related to individual video camera identification using a correlation coefficient of fixed pattern noise (FPN) in image sensors. Five color charge-coupled device (CCD) modules of the same brand were examined. Images were captured using a 12-bit monochrome video capture board and stored in a personal computer. For each module, 100 frames were captured. They were integrated to obtain FPN. The results show that a specific CCD module was distinguished among the five modules by analyzing the normalized correlation coefficient. The temporal change of the correlation coefficient during several days had only a negligible effect on identifying the modules. Furthermore, a positive relation was found between the correlation coefficient of the same modules and the number of frames that were used for image integration. Consequently, precise individual camera identification is enhanced by acquisition of as many frames as possible.  相似文献   
5.
Two major salvinorins, salvinorin A (SalA) and salvinorin B (SalB), in three Salvia divinorum dried leaf products and nine of its “concentrated extract” products circulated in Japan were determined. These ingredients were extracted twice with acetonitrile and decolored with graphite carbon powder. SalA and SalB were confirmed by liquid chromatography–tandem mass spectrometry in product ion scan mode, and quantified by high-performance liquid chromatography with UV detection (for SalA) and by mass spectrometry in single ion monitoring mode (for SalB). The SalA/SalB contents (μg/mg) were in the range of 3.2–5.0/0.10–0.17 in the dried leaf products and 4.1–38.9/0.26–2.42 in the “concentrated extract” products. These findings would be useful for analysis of S. divinorum-related products circulated in the drug market.  相似文献   
6.
Forensic laboratories are often faced with cases in which methamphetamine hydrochloride‐mixed blood is unable to be identified as human blood by immunochromatography against human hemoglobin A0. The application of mRNA expression analysis to samples that showed a false‐negative with immunochromatography was investigated as an alternative approach that did not depend on the antigen–antibody reaction. Real‐time PCR was used to examine the expression levels of blood markers such as glycophorin A, spectrin beta, and hemoglobin beta. Hemoglobin beta was the only marker that was specifically detected in blood, while glycophorin A was useful for determining human specificity. Hemoglobin beta showed good detection sensitivity and was detectable in 37‐year‐old blood stains. Hemoglobin beta was exclusively detectable in methamphetamine hydrochloride‐mixed blood stains. Detergents and disinfectants did not significantly influence mRNA markers. The proposed mRNA expression analysis was suitable for human blood identification as an alternative method to immunochromatography.  相似文献   
7.
This is the first report on development of a library search‐based screening system for 3,4‐methylenedioxymethamphetamine (MDMA) in ecstasy tablets using a portable near‐infrared (NIR) spectrometer. The spectrum library consisted of spectra originating from standard substances as well as mixtures of MDMA hydrochloride (MDMA‐HCl) and diluents. The raw NIR spectra were mathematically pretreated, and then, a library search was performed using correlation coefficient. To enhance the discrimination ability, the wavelength used for the library search was limited. Mixtures of MDMA‐HCl and diluents were used to decide criteria to judge MDMA‐positive or MDMA‐negative. Confiscated MDMA tablets and medicinal tablets were used for performance check of the criteria. Twenty‐two of 27 MDMA tablets were truly judged as MDMA‐positive. Five false‐negative results may be caused by compounds not included in the library. No false‐positive results were obtained for medicinal tablets. This system will be a useful tool for on‐site screening of MDMA tablets.  相似文献   
8.
The opioid epidemic, impacted from the proliferation of fentanyl, has added impetus to the need to detect fentanyl, sources of fentanyl, and places where fentanyl and drugs adulterated with fentanyl are available. Many darknet marketplaces (DNMs) have rules that ban fentanyl. However, it is unclear how these affect the fentanyl market. Using the AlphaBay DNM as a case study, we conducted mixed methods qualitative research. We scraped and analyzed data from the AlphaBay I2P website using, among other methods, content and social network analysis, to uncover hidden fentanyl networks. Our research highlights the next evolution of darknet marketplaces – the migration of DNMs from Tor to I2P and the methods that can be used identify fentanyl networks, irrespective of where sites are: I2P, Tor, or multihomed on I2P and Tor. Despite its ban in the Global AlphaBay Rules, our research revealed the sale of fentanyl on the AlphaBay DNM. Unlike previous studies, our findings predominantly revealed the covert sale of fentanyl on AlphaBay and predatory vendors selling illicit drugs, which unbeknownst to buyers, contained fentanyl. To a lesser extent, our findings identified the overt sale of fentanyl patches on AlphaBay. Although we examined only one DNM, the prevalence of the covert sale of fentanyl and the presence of predatory vendors underscores the importance of research that decodes the language of vendors who surreptitiously sell fentanyl or drugs adulterated with fentanyl or other illicit substances. The results of our research can inform strategies aimed at disrupting and dismantling DNM fentanyl networks.  相似文献   
9.
This paper uses insights drawn from a paired comparison of Switzerland and Japan to give an account of the changes brought about by neoliberal policy adaptation in Japan over the last two decades. In Switzerland, notwithstanding further liberalization of the traditionally liberal regime prompted by the economic hardships of the 1990s, the referendum system helped the Social Democrats and unions to defend their rights and maintain the welfare schemes belatedly established in the 1980s. By contrast, the Japanese ruling party not only delayed liberalization of the protectionist state, but also aggravated fiscal problems by implementing a series of expansionary macroeconomic policies in the 1990s. Thus, without pursuing coherently such neoliberal policies as fiscal consolidation, privatization, or market deregulation, the Japanese state now faces a serious dilemma between the immediate need for structural reforms and the social unease that would result. Focusing on the reform packages of the Nakasone (1982‐87), Hashimoto (1996‐98), and Koizumi (2001‐) administrations, the paper reviews the sequences of reform policies as an interplay among economic challenges, actors’ aspirations, and institutional constraints, and further develops arguments about the segmented structure, peculiar to the Japanese state, that retards political changes.  相似文献   
10.
Impurity profiling of methamphetamine (MA) using thermal desorption (TD) and gas chromatography-mass spectrometry (GC-MS) was examined. Using TD/GC-MS, impurities were extracted and separated under various conditions. Optimal chromatograms were obtained when a 20 mg MA sample was extracted at 120 degrees C for 3 min using a TD instrument, followed by separation of the extracts using a non-polar capillary column coated with (5%phenyl)-methylpolysiloxane. MA samples from nine different batches were analyzed under optimized conditions. Compounds related to the structure of MA, such as benzaldehyde, benzyl alcohol, amphetamine, cis- and trans-1,2-dimethyl-3-phenylaziridine, dimethylamphetamine, and N-acetylephedrine, were detected in the chromatograms without any laborious extraction procedure. Compounds such as ethanol, diethyl ether, and acetic acid, which are considered reagents and solvents for MA synthesis, were also detected in some of the chromatograms. The numbers and intensities of the peaks detected were different among the samples. Impurity profiling of MA using TD was compared with that using liquid-liquid extraction (LLE). Better reproducibility of peak areas was obtained using LLE, whereas higher intensities and numbers of peaks were detected using TD. Solvents were extracted more effectively using TD. The nine batches of MA were classified using both extraction procedures. The nine batches were divided roughly into two groups using data from LLE. Subsequently, the groups were classified in detail using data from TD. TD can be used to provide supplemental information for LLE, and the combination of these extraction methods can be helpful for impurity profiling of MA.  相似文献   
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