Peak Oil as a stimulus for a green economy transition in South Africa: Alternative liquid fuel and transport options

Abstract

While the arguments in favour of a green economy often rest on the need to reduce environmental damage, mitigate climate change and create environmentally friendly jobs, this article argues that the inevitable and possibly imminent peak and decline in world oil production provides another strong rationale for green economy policies and investments in South Africa. The South African economy has a high degree of reliance on imported petroleum fuels and evidence suggests that oil price and supply shocks – resulting from diminishing world oil exports and a decline in the energy return on investment for oil globally – are likely to have a debilitating socioeconomic impact under business-as-usual policies and behaviour patterns. Two broad strategies for mitigating the impact of increasing world oil scarcity and oil price shocks are considered. The first evaluates the prospects for developing indigenous sources of liquid fuels, including coal-to-liquids, gas-to-liquids and biofuels, and finds that there are significant resource and environmental risks associated with these options. The second strategy involves short-term measures to reduce demand for liquid transport fuels together with a long-term shift toward electrified mass transport, supported by accelerated investments in renewable energy. The latter strategy is argued to be compatible with and necessary for a societal transition towards a green economy.     

Analysis and Discrimination of Single‐Layer White Architectural Paint Samples,

Comparative analyses of 50 single‐layer white architectural paints were conducted to determine the discrimination power using standard techniques and to provide a basis for assessing significance when paints with limited features are not discriminated. Utilizing Fourier transform infrared spectroscopy (FTIR), 68 undifferentiated pairs resulted, yielding a discrimination of 94.45%. Adding stereomicroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and backscatter electron (BSE) imaging, and pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS), the overall discrimination was 99.35%. The study included blind verification replicates, which resulted in the only pairs without indications of physical or chemical differences. The remaining groups of undifferentiated samples contained subtle differences by at least one technique, but were considered undifferentiated for the discrimination power evaluations. This study demonstrates a high degree of discrimination of single‐layer white architectural paints using methods of analysis often encountered in forensic science laboratories.     

Methyl tert‐Butyl Ether (MTBE) Detected in Abnormally High Concentrations in Postmortem Blood and Urine from Two Persons Found Dead Inside a Car Containing a Gasoline Spill

Two deep frozen persons, a female and a male, were found dead in a car. There had been an explosive fire inside the car which had extinguished itself. On the floor inside the car were large pools of liquid which smelled of gasoline. The autopsy findings and routine toxicological analyses could not explain the cause of death. Carboxyhemoglobin levels in the blood samples were <10%. Analysis with a headspace gas chromatography revealed methyl tert‐butyl ether (MTBE) concentrations of 185 mg/L (female victim) and 115 mg/L (male victim) in peripheral blood. The urine MTBE concentrations were 150 mg/L and 256 mg/L, respectively. MTBE is a synthetic chemical which is added to gasoline as a fuel oxygenate. Gasoline poisoning is likely to be the cause of the death in these two cases, and MTBE can be a suitable marker of gasoline exposure, when other volatile components have vaporized.     

不同炮制温度和时间对炮姜中姜酮含量的影响

目的 考察不同炮制温度和时间对炮姜中姜酮含量的影响。方法 采用超高效液相色谱法对15份不同炮制温度和炮制时间的炮姜样品中姜酮含量进行测定。色谱条件：色谱柱为Acquity BEH C18（100 mm×2.1 mm,1.7 μm）;流动相为乙腈-水,梯度洗脱;流速0.3 ml/min,检测波长280 nm,柱温30 ℃。结果 姜酮进样量在0.073 2～0.366 0 μg时与峰面积呈良好的线性关系（r=0.999 8）,平均加样回收率为97.42%（RSD=2.35%）。炮姜中姜酮含量随着炮制温度和时间的变化明显,以炮制温度为200 ℃、炮制时间为6 min时样品中姜酮含量最高。结论 炮制过程中姜酮含量随着温度升高和时间延长呈现先升高后降低的趋势,所建立的超高液相色谱法简便、准确、重现性好,可用于炮姜中新生成分姜酮的测定。     

Proteolytic‐Based Method for the Identification of Human Growth Hormone*

Abstract: Human growth hormone (HGH) is a relatively small protein consisting of 191 amino acids and has an average mass of 22,125 amu. The forensic analysis of proteins such as HGH must meet the analytical sufficiency requirements for the laboratory and consists of a binary approach. A suspected sample is analyzed as the whole protein for retention time and mass determination using high performance liquid chromatography equipped with a photodiode array and liquid chromatography mass spectrometry. Further fragmentation of the protein using a proteolytic enzyme adds another dimension to the specificity of the analysis. Porcine trypsin digests proteins in a very predictable manner and yields peptide fragments of the original protein that can be used as a means for fingerprinting the larger biomolecule. In silico, or theoretical, digestion of HGH by trypsin yields 21 peptides ranging in size from 1 to 23 amino acids in length. The larger fragments containing higher numbers of amino acids give more specificity to identifying a protein based on a fragment produced by the digestion of trypsin. Herein, the analysis of HGH using a proteolytic approach is presented that meets the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) recommendations for the identification of unknown substances.     

Identification of acepromazine in hair: an illustration of the difficulties encountered in investigating drug-facilitated crimes

After a drug-facilitated sexual assault (DFSA), a woman was found in a drowsy state at home. She remembered having drunk an unknown beverage by the accused. Blood samples (collected 8 hours after the DFSA), two glasses, and a teaspoon seized by the police were analyzed. Acepromazine, a phenothiazine tranquilizer used in human and veterinary medicine, was detected in the residue of one of the glasses. In spite of acepromazine absence in the victim's blood, the possible use of acepromazine in the DFSA was reported to the police. Two weeks later, a suspect admitted having orally administered acepromazine to the victim. Using a liquid chromatography-tandem mass spectrometry method, this compound was subsequently detected (31 pg/mg) in a sample of the victim's hair collected a month and a half after the DFSA. A potential short elimination half-life in humans and/or the well-known in vitro degradation of acepromazine could explain the negative blood result. DFSA toxicological investigations are challenging and can be complicated when a rather unusual substance is concerned. In particular, special care should be taken when interpreting the results, taking into account elimination and/or instability data, when available.     

Bromadiolone poisoning: LC-MS method and pharmacokinetic data

Abstract:  Poisoning with superwarfarins, like bromadiolone, is a growing public health problem, and the mortality is high. Pharmacokinetic data on bromadiolone in humans are however scarce, and there are no reports following repeated exposures to bromadiolone. We have developed a method for quantification of bromadiolone in whole blood, using liquid chromatography–mass spectrometry (LC-MS). The analytical method is reported. Limit of detection was 0.005 mg/L and limit of quantification was 0.01 mg/L. The concentrations of bromadiolone in whole blood and plasma in serial samples from a 62-year-old woman were measured. The half-life of bromadiolone in blood was estimated to be about 6 days in the initial phase of elimination and about 10–13 days in the terminal phase. The mean plasma/blood ratio of bromadiolone was 1.7 ± 0.6. Stability testing of bromadiolone in whole blood samples after two cycles of freeze and thaw revealed that bromadiolone concentrations decreased.     

Utility of immunoassay in drug screening in skeletal tissues: sampling considerations in detection of ketamine exposure in femoral bone and bone marrow following acute administration using ELISA

Detection of ketamine exposure in skeletal tissues by automated enzyme-linked immunosorbent assay (ELISA) and gas chromatography with electron capture detection (GC-ECD) is described. Rats (n = 18) received 0, 15, 30, or 75 mg/kg ketamine hydrochloride acutely (i.p.), and were euthanized within 15 min or 1 h. Ketamine was extracted from ground femoral bone by methanolic incubation followed by liquid-liquid extraction (LLE), while marrow was homogenized in alkaline solution, and then underwent LLE. Extracts were analyzed by ELISA, and subsequently by GC-ECD following derivatization with trifluoroacetic acid anhydride. The effect of tissue type (i.e., diaphyseal bone vs. epiphyseal bone vs. bone marrow) on the immunoassay response was examined through determination of binary classification test sensitivity (S) and measurement of the relative decrease in absorbance (%DA, drug-positive tissues vs. drug-free controls) in each tissue type. The %DA varied significantly between different tissues examined under a given dose condition, and generally decreased in the order marrow > epiphyseal bone > diaphyseal bone, at all dose levels examined. Measured S values for marrow, epiphyseal bone, and diaphyseal bone were 100%, 77%, and 23%, respectively (75 mg/kg dose). These results suggest that the type of skeletal tissue sampled and position sampled within a given bone (diaphyses vs. epiphyses) are important parameters in drug screening of skeletal tissues.     

LC-MS／MS测定尿液中可卡因及其代谢物苯甲酰爱康宁

目的建立尿液中可卡因(cocaine,COC)及其代谢物苯甲酰爱康宁(benzoylecgonine,BZE)的液相色谱-串联质谱分析方法。方法尿液经固相萃取后,用AllurePFP丙基柱分离,以V(甲醇):V(20mmol/L乙酸胺和0.1%甲酸的缓冲溶液)=80∶20为流动相,采用二级质谱多反应监测模式检测COC和BZE。按10mg/kg的剂量对豚鼠腹腔注射可卡因,给药后收集7d尿液。结果尿液中COC和BZE在2.0～100ng/mL质量浓度范围内线性关系良好(r=0.9995),最低检测限(LOD)为0.5ng/mL;回收率大于90%;日内和日间精密度均小于6%;豚鼠尿液中主要检测目标物是BZE,且BZE检测时限也较COC长。结论所建方法灵敏度高,选择性好,适用于尿液中可卡因和苯甲酰爱康宁的检测。     

A solid-phase microextraction method for the detection of ignitable liquids in fire debris

A solid-phase microextraction (SPME) procedure involving direct contact between the SPME fibers and the solid matrix and subsequent gas chromatography/mass spectrometric analysis for the detection of accelerants in fire debris is described. The extraction performances of six fibers (100 mum polydimethylsiloxane, 65 mum polydimethylsiloxane-divinylbenzene, 85 mum polyacrylate, 85 mum carboxen-polydimethylsiloxane, 70 mum Carbowax-divinylbenzene, and 50/30 mum divinylbenzene-Carboxen-polydimethylsiloxane) were investigated by directly immersing the fibers into gasoline, kerosene, and diesel fuel. For simulated fire debris, in the direct contact extraction method, the SPME fiber was kept in contact with the fire debris matrix during extraction by penetrating plastic bags wrapping the sample. This method gave comparable results to the headspace SPME method in the extraction of gasoline and kerosene, and gave an improved recovery of low-volatile components in the extraction of diesel fuel from fire debris. The results demonstrate that this procedure is suitable as a simple and rapid screening method for detecting ignitable liquids in fire debris packed in plastic bags.