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31.
SNIF-NMR (Site-specific natural isotopic fractionation measured by deuterium NMR) was employed on 36 heroin samples from seven different known origins, and two cocaine samples from two different known origins. Heroin has two "synthetic" deuterium labeled sites (the two acetyls from acetic anhydride, each representing three equivalent nuclei) and 15 "natural" deuterium labeled sites (originating from the morphine produced in the opium plant). The "natural" sites have the potential for determining geographic location of the original opium plant, while the "synthetic" sites could assist in giving information about the commercial source of acetic anhydride used to convert morphine to heroin. Cocaine has 15 "natural" deuterium labeled sites. This study shows that SNIF-NMR has some use in determining the geographic origin of heroin and also has good potential for determining the geographical origin of cocaine.  相似文献   
32.
Abstract:  A clandestine chemist was observed producing heroin from crude morphine utilizing a solution of sodium hypochlorite during the process. Numerous chlorinated opium alkaloid derivatives were created when the morphine acetylation reaction was quenched and neutralized with a solution of sodium hypochlorite and ammonium hydroxide. Four of these compounds, 1-chloroheroin, 1-chloroacetylcodeine, 1-chloro-O6-monoacetylmorphine, and 2'-chloropapaverine, were characterized via preparative isolation, gas chromatography/mass spectrometry, nuclear magnetic resonance spectroscopy, and independent synthesis. These chlorinated derivatives were formed via electrophilic aromatic substitution with free chlorine during the illicit process. Although no illicit heroin exhibits containing these compounds have been observed in seizures to date, mass spectral data are provided for several of these compounds for their identification should they be seen within future seizures of illicit heroin.  相似文献   
33.
Hays  R. Allen 《Publius》1988,18(1):79-95
This article examines relationships between state agencies andlocal communities, using survey and interview data from a casestudy of the Iowa Department of Transportation. It argues thatthese relationships often parallel the agency-clientele relationshipsobserved by public administration scholars. The agency derivessimilar benefits from local government support as from privateclientele support, namely, an independent power base that helpsto preserve its flow of resources and its administrative autonomy.IDOT possesses formidable political resources in the breadthand intensity of its clientele, but the key to IDOT's successis the skillful utilization of those resources through an administrativestrategy stressing the development of widely accepted technicaldecision-criteria and an administrative style emphasizing accessibility,responsiveness, and flexibility. A survey of mayors and localbusiness leaders shows that this strategy has generated widespreadpositive perceptions of the department among these clientelegroups.  相似文献   
34.
Laudanosine, reticuline, codamine, and laudanine are members of the tetrahydrobenzylisoquinoline family of natural products. These alkaloids are present in the opium poppy, Papaver somniferum, and are subsequently found as impurities in clandestinely processed morphine. Morphine is then synthesized to heroin using hot acetic anhydride. During the course of this study, it was determined that these four tetrahydrobenzylisoquinolines undergo degradation to a series of 18 neutral impurities when subjected to hot acetic anhydride. Based on the degradation pathway, these new impurities were categorized into two sets of impurities called the C1-acetates compounds and the stilbene compounds. Synthesis, isolation, and structural elucidation information is provided for the tetrahydrobenzylisoquinoline alkaloids, and the new neutral impurities have been studied. Several hundred authentic heroin samples were analyzed using an established heroin signature program method. This methodology features the detection of trace neutral impurities present in heroin samples. It was determined that all 18 new impurities were detected in various quantities in four different types of heroin samples. Analytical results featuring these new impurities are reported for South American-, Southwest Asian-, Mexican-, and Southeast Asian-type heroin samples. These new impurities, coupled with other established forensic markers, enhance the ability to classify illicit heroin samples.  相似文献   
35.
A rapid, sensitive, accurate, precise, reproducible, and versatile method for determining the purity of reference drug standards and the routine analysis of illicit drugs and adulterants using proton (1H) Nuclear Magnetic Resonance (NMR) Spectroscopy is presented. The methodology uses a weighed sample dissolved in a deuterated solvent or solvent mixture containing a high purity internal standard. The NMR experiment employs 8 scans using a 45 second delay and 90 degrees pulse. In the determination of purity of reference standards, the number of quantitative determinations available is equal to the number of peak groups that are baseline resolved. The relative standard deviation (RSD) of these signals is usually < 1% for pure standards, and the results agree well with other purity determining methods. This method can also aid in the determination of correct molecular weight for standards containing an unknown number of waters of hydration or an unknown number of acids per drug in salts. Because the molar response for the hydrogen nucleus is 1 for all compounds, and since no separation media are used, only one linearity study is required to test a probe. In the presented study, the linearity of the NMR probe was determined using methamphetamine HCl dissolved in deuterium oxide (D2O) with maleic acid as the internal standard (5 mg) for a range of concentrations from 0.033 to 69.18 mg/ml with a resulting correlation coefficient of >0.9999 for all 6 methamphetamine peak groups. The spectra of complex illicit heroin, methamphetamine, MDMA, and cocaine samples are presented, as well as an extensive list of compounds, their solubilities and the solvent(s) and internal standard used.  相似文献   
36.
A rapid, accurate, precise, reproducible, economical, and environmentally gentle method using capillary electrophoresis (CE) is presented for the routine analysis of methamphetamine, amphetamine, MDA, MDMA, MDEA, and cocaine in seized drugs. The methodology uses a 32 cm by 50 microm capillary (length to detector 23.5 cm) with a commercially available buffer kit and diode array UV detection. Dynamic coating of the capillary surface is accomplished by flushing with base for 1 min, a proprietary polycation for 1 min, and then a proprietary polyanion for 2 min. This approach provides a relatively high and stable electroosmotic flow (EOF), even at low pHs. The background electrolyte (BGE) contains 75 mM phosphate buffer (pH 2.5) with the same polyanion as above. Using this methodology, amphetamine, methamphetamine, MDA, MDMA, MDEA, and an internal standard (n-butylamphetamine) are baseline resolved in less than 5 min. The run-to-run migration time %RSDs and peak area %RSDs are typically <0.3% and <2.1%, respectively. The day-to-day and capillary-to-capillary migration time %RSDs are <1.5% and <2.1%, respectively. The %RSDs of the relative migration times compared with the internal standard on a day-to-day and capillary-to-capillary basis are <0.2% and <0.06%, respectively. The linear dynamic range using peak areas range from 0.003 to 0.10 mg/mL. The correlation coefficients are >0.9998, with all calibration curves passing at or near the origin. Similar data are obtained for cocaine and its internal standard henyltoloxamine. None of the compounds usually encountered in illicit samples interfere with the target compound (e.g., methamphetamine and cocaine) or the internal standard. Quantitative results for synthetic mixtures and seized exhibits are in good agreement with actual values, and also with results obtained from other techniques. The relatively high EOF for the dynamically coated capillary system allows for the screening of basic, acidic, and neutral adulterants in drug seizures; identification is facilitated by the use of automated UV library searches.  相似文献   
37.
This case report describes an incident of myiasis in Oklahoma City, Oklahoma. Paramedics treated a 53‐year‐old man in the field when he suffered cardiac arrest. He was intubated by the paramedics and transported to an emergency room, where he received two stents and a balloon pump. He was found to have a GCS of three and remained in the hospital for 7 days before passing away. After his death, the breathing tube was removed, revealing the presence of several maggots. On closer inspection, the dipteran larvae were found in both the oral and nasal cavities. Four of these larvae were reared to adulthood and identified as Lucilia cuprina (Weidemann) (Diptera: Calliphoridae), commonly known as the Australian sheep blowfly, by the Biology Department of the University of Oklahoma. Based on the fly's life cycle and rate of development, the infestation is suspected to be hospital acquired.  相似文献   
38.
This article examines the progress of professionalization within a highly traditional political and social setting. The impact of such characteristics as a decentralized personnel system, fragmented political authority, and an absence of top-level support is assessed in the context of current initiatives to upgrade the professional orientations and capabilities of the state's workers. The primary theme is that, despite the lack of an integrated professionalism movement in state government, remarkable advances have occurred, and are continuing at an impressive pace. The impetus for these changes is found to be in the various employee groups that are striving to enhance their professional skills and status.  相似文献   
39.
兰萨案的判决涉及到美国版权领域的重要问题———平行进口问题 ,版权作品经过版权人的同意或者版权人自己首次投入市场后 ,版权人对于版权作品中包含的权利是否用尽直接关系到商品在市场上能否自由流动 ,知识产权人从自身的利益出发反对版权作品进入特定的市场 ,严格控制此类产品的销售渠道 ,目的是为了维护其版权作品的高价格 ,但是 ,版权人的行为可能违反竞争法  相似文献   
40.
平行进口是欧洲法院面临的一个棘手问题 ,欧洲共同体各成员国国内知识产权立法上的差异导致商品自由流动出现障碍 ,知识产权人利用国内立法通过协议或采取统一行为限制知识产权产品进入特定的市场 ,保护自己的利益 ,减少商业风险 ,避免竞争 ,实际上分割了市场 ,导致了包含在商品中的权利用尽。商品必须处于自由流通的状态 ,任何阻碍商品自由流动 ,影响成员国贸易的行为都是违反欧洲共同体条约第 81条的反竞争行为  相似文献   
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