The Analysis of Black Powder Substitutes Containing Ascorbic Acid by Ion Chromatography/Mass Spectrometry*†

Abstract: Black powder substitutes containing ascorbic acid are a group of low explosives that utilize ascorbic acid as the fuel. The analysis of these powders is complicated by the degradation of ascorbic acid which occurs rapidly in solution and may also occur as the powder ages. Aqueous extracts of both intact powders and postblast residues were analyzed by an existing ion chromatography/mass spectrometry (IC/MS) method used at the Bureau of Alcohol, Tobacco, Firearms and Explosives. Results have shown that while ascorbic acid itself is not detected in this method, its diagnostic degradation products (threonic acid, monohydrated diketogulonic acid, and oxalic acid) can be identified. In addition, anions from the inorganic oxidizers (perchlorate and nitrate) and combustion products such as chloride, chlorate, and nitrite, can be identified within the same experiment. While this IC/MS method shows promise, future modifications are necessary because of limitations in identifying threonate in postblast residues, as well as coeluting compounds observed in postblast residues.     

Discriminating Hodgdon Pyrodex® and Triple Seven® Using Gas Chromatography–Mass Spectrometry

Abstract: Pyrodex ^® and Triple Seven ^® are black powder substitutes that often find use as fillers in improvised explosive devices, such as pipe bombs. These propellants have essentially the same overall appearance and oxidizers, but different fuels. For example, Pyrodex ^® contains sulfur, sodium benzoate, and dicyandiamide (DCDA), whereas Triple Seven ^® lacks sulfur but also contains 3‐nitrobenzoic acid. In this method, intact particles and postblast solid residues were reacted with bis(trimethylsilyl)trifluoroacetamide + 1% trimethylchlorosilane in acetonitrile for 30 min at 60°C. The resultant trimethylsilyl derivatives of the organic fuels were then analyzed by gas chromatography–mass spectrometry. Each derivative was clearly resolved from other components, and high‐quality mass spectra were obtained. In addition, characteristic fragments resulting from loss of a methyl radical from the molecular ion (m/z 163 for sulfur, m/z 171 for DCDA, m/z 179 for benzoic acid, and m/z 224 for nitrobenzoic acid) were able to be monitored.     

Enantiomeric Identification of Pregabalin by GC‐MS via Methylation and S‐TPC Chiral Derivatization

Pregabalin is a Schedule V controlled substance which is defined as the (S) enantiomer of 3‐(aminomethyl)‐5‐methylhexanoic acid. It is used legitimately to treat neuropathy in patients with diabetes as well as for epilepsy and fibromyalgia. Pregabalin is an amino acid and an amphoteric compound, which makes it difficult to analyze using the conventional GC‐MS instrumentation found in most forensic drug analysis laboratories. Problems associated with the traditional GC‐MS analysis of pregabalin include selective solubility, ring closure to the corresponding lactam in the GC injection port and/or the MS transfer line and difficulty with chiral derivatization due to the presence of a carboxylic acid moiety. Here, we show that these challenges can be overcome by methylating (capping) the carboxylic acid portion of the pregabalin molecule and converting to the corresponding methyl ester. Once the methyl ester is synthesized, chiral derivatization at the amine can be achieved to identify the controlled (S) enantiomer of pregabalin via GC‐MS.     

Identification and characterization of the new designer drug 4'-methylethcathinone (4-MEC) and elaboration of a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) screening method for seven different methcathinone analogs

A fast and simple LC-MS/MS method was developed for screening mephedrone, butylone, methylenedioxypyrovalerone (MDPV), flephedrone, methylone and methedrone in bulk powder samples. Samples were separated on a reverse phase column using gradient elution with mixtures of water, acetonitrile and formic acid. After optimization a limit of detection of about 2ngmL(-1) was achieved using multiple reaction monitoring (MRM) mode. Total run time was less than 8min. Typical fragmentation characteristics of the studied compounds are discussed. The method was successfully applied to several unknown bulk powder samples seized by the Hungarian Customs and Finance Guard. One of the samples contained the new designer drug 4'-methylethcathinone (4-MEC), which was identified and characterized by LC-MS/MS, NMR, FT-IR and LC-TOF-MS techniques. The method is also deemed to be applicable for the screening of simple dosage forms such as tablets and capsules.     

Columnar‐Thin‐Film‐Assisted Visualization of Depleted Sebaceous Fingermarks on Nonporous Metals and Hard Plastics

A fingermark on a nonporous substrate can be developed by depositing a columnar thin film (CTF) on it, but the CTF technique's sensitivity for low‐quality fingermarks is unknown. The optimized CTF and traditional development of several depletion series of sebaceous‐loaded fingermarks were compared using a split‐print methodology as well as subjective and objective grading schemes, in a limited laboratory trial. CTF development was superior to development with selected traditional techniques on brass, anodized aluminum, black acrylonitrile butadiene styrene (ABS), and white nylon. On white ABS and black nylon, the CTF technique performed poorly but still as well as the best‐performing traditional development technique. The CTF technique was more sensitive on brass and anodized aluminum than, and as sensitive on the four hard plastics and stainless steel as, the best‐performing traditional technique. Thus, the CTF technique is useful to develop friction‐ridge detail from limited fingermark residue on some smooth substrates.     

Penetration Depth of Projectiles Fired from a Replica of Colt Navy of 1851 in 20% Gelatin Blocks Correlated with Fatal Injuries Assessed in an Autopsy of a 78‐Year‐Old Man

Pursuant to the Polish Weapons and Ammunitions Law, muzzle‐loading black powder weapons, manufactured before 1885, or their replicas, as well as suitable projectiles, can be possessed legally without registration and special licenses. The aim of the study was to assess the penetration depth of projectiles fired from a black powder weapon, replica of Colt Navy of 1851, in 20% gelatin blocks and to compare the obtained results with the actual injuries found on autopsy of a 78‐year‐old man who had committed suicide. In the experiments, we used the black powder weapon and ammunitions, as well as gelatin blocks serving as a soft tissue model. We ascertained that solid spherical projectiles fired from black powder weapons cause extensive injuries, especially in the initial segment of the wound canal. Additionally, based on the presence and location of the wad in the wound canal, the distance from which the shot was fired can be determined.     

A preliminary investigation into the acquisition of fingerprints on food

The potential for enhancement and recovery of latent fingerprints on a variety of foodstuffs has been investigated. In general, black magnetic powder and black powder suspensions appear to be the most successful enhancement techniques with a high number of ridge detail-developed prints over a selected time scale. Banana, apple and tomato surfaces showed enhancement of latent prints but potato and egg surfaces proved to be less successful.     

The effect of mark enhancement techniques on the presumptive and confirmatory tests for blood

An investigation into the effects of physical and chemical enhancement on subsequent presumptive and confirmatory tests for human blood is presented. Human blood was deposited onto porous (white 80 gsm paper and brown envelope) and non-porous (tile and linoleum) substrates in a depletion series (30 depletions on non-porous and 20 on porous) and subjected to three ageing periods; 1, 7 and 28?days. A number of enhancement techniques were tested [fluorescence, black magnetic powder (BMP), iron-oxide black powder suspension (PS), cyanoacrylate (CA) fuming, acid violet 17 (AV17), acid yellow 7 (AY7), ninhydrin, DFO and Bluestar Forensic Magnum (BFM) luminol] to evaluate their potential effects on subsequent presumptive and confirmatory tests. AV17 and Bluestar provided the best enhancement and fully enhanced all depletions in the series. The sensitivity of the Kastle-Meyer (KM) (presumptive), Takayama and RSID-Blood tests (confirmatory) was initially investigated to determine the range of detectable depletions. The KM test detected all depletions, whereas the Takayama test detected up to depletion 6 and RSID-Blood detected up to depletion 20 (paper), 10 (envelope), 15 (tile) and 9 (lino). The abilities of these tests to detect blood after enhancement were then observed.A number of techniques resulted in little to no effect on any of the blood tests, whereas adverse effects were observed for others. Ninhydrin and CA fuming caused weak but instantaneous positive KM results whereas methanol-based AV17 and AY7 delayed the reaction by as much as 1?min. The Takayama test was not very sensitive, therefore, its performance was easily affected by enhancement and negative results were often observed. RSID-Blood tests were largely unaffected by chemical enhancement although a drop in positive results was observed for some of the techniques when compared to positive controls.Using a standard procedure for DNA extraction, all the tested blood samples (before and after enhancement) gave a detectable quantity of DNA and were successfully profiled. Out of the 45 samples processed for DNA profiling, 41 gave full profiles, while the remaining showed allele drop out in one or two loci.     

Classification of black powder toners on the basis of integrated analytical information provided by Fourier transform infrared spectrometry and X-ray fluorescence spectrometry

Differentiating between black powder toners used in laser printers and copiers can be challenging for forensic examiners. One hundred and sixty-two samples from 82 different types of cartridges produced by 21 manufacturers that are currently available on the Polish market were studied using Fourier transform infrared spectrometry (FT-IR) and energy-dispersive X-ray fluorescence spectrometry (XRF). The spectra obtained by these two methods were classified into 14 groups and 28 groups using FT-IR and XRF, respectively. These classifications served as a basis for the development of an analytical scheme for differentiating black powder toners. This scheme can be used with any two methods that supply different information about an examined sample. The research will show that if two samples are similar in polymer composition (e.g., FT-IR spectra), additional quantitative elemental composition from XRF analyses may provide more discrimination. It was possible to differentiate 82.5% pairs of examined samples using only FT-IR, 90.8% pairs of examined samples using only XRF, and 95.8% pairs of examined samples using these two methods. Obtained spectra and all the available information could be used to create/build a database. The results obtained confirm the multiplicity and compatibility of toners. Additionally, it was stated that not all the samples were original (OEM).     

Validation of LAB color mode as a nondestructive method to differentiate black ballpoint pen inks

Nondestructive digital processing methods such as lab color mode (available in Adobe Photoshop) are emerging as alternative methods for forensic document examiners to use when attempting to differentiate writing instrument inks. Although these techniques appear to be viable, little data currently exists regarding the known or potential error rates associated with these techniques. Without adequate data, the validity and reliability of these techniques, including lab color, can not be established. In an attempt to begin to address these issues, 44 black ballpoint ink pens were obtained and used to create 990 pen-pair samples for analysis using established lab color mode techniques. No erroneous findings of "different" were reported following the examination of the known pen-pair combinations in which the same pen was used to create the samples (n = 44). Of the remaining 946 samples, 737 pen-pair samples were differentiated using the lab color mode method, while 209 samples were unable to be differentiated and were recorded as either being "similar" (n = 153) or "unsure" (n = 56). Comparison of the lab color mode results with the results obtained through additional testing using traditional infrared reflectance and infrared luminescence test methods showed that lab color differentiated 102 pen-pair samples (11%; 102/946) that were not differentiated using a VSC-4C.     

新型亲油性纳米二氧化硅粉末在手印显现中的应用

目的 比较新型亲油性纳米二氧化硅粉末显现手印的效果.方法 应用亲油性纳米二氧化硅粉末与现场勘查箱内金粉、银粉和黑色磁性粉显现非渗透性客体表面油汗混合手印,并在自然光下观察比较显现效果.结果 亲油性纳米二氧化硅粉末显现出的手印图像纹线清晰连贯,背景反差好.结论 亲油性纳米二氧化硅粉末显现手印具有一定的优势.     

Lifting techniques for finger marks on human skin previous enhancement by Swedish Black powder — A preliminary study

An examination was done to investigate whether certain lifting techniques can lift recovered latent fingerprints on human skin surfaces of living subjects. For recovery Swedish Soot powder mixture (Swedish Black) was used.Donors intentionally placed fingerprints on the skin surface of living subjects. Finger marks were then in all cases recovered with Swedish Black powder. The procedure was repeated after 1 h and 4 h. Treated finger marks were secured and preserved as latent fingerprint evidence by different lifting processes. Having examined skin surfaces and finger marks we observed that the lifters such as white instant lifter, white fingerprint gelatin, black fingerprint gelatin, silicone, transparent adhesive tape, are suitable. Moreover, white fingerprint gelatin and white instant lifter proved to be very good at lifting treated finger marks. Black fingerprint gelatin was very good also, but finger marks were examined by slant light.     

EDX、XRD法定性分析混合火药的主要成分

目的建立检验自制混合火药方法。方法用扫描电镜、X射线衍射仪,测定自制混合火药的主要成分,结果准确可靠。结果既可测定火药成分,还可区分石墨晶片和植物性炭。结论两种方法可用于火药鉴定。     

How to Cautiously Uncover the “Black Box” of Machine Learning Models for Legislative Scholars

Machine learning models, especially ensemble and tree-based approaches, offer great promise to legislative scholars. However, they are heavily underutilized outside of narrow applications to text and networks. We believe this is because they are difficult to interpret: while the models are extremely flexible, they have been criticized as “black box” techniques due to their difficulty in visualizing the effect of predictors on the outcome of interest. In order to make these models more useful for legislative scholars, we introduce a framework integrating machine learning models with traditional parametric approaches. We then review three interpretative plotting strategies that scholars can use to bring a substantive interpretation to their machine learning models. For each, we explain the plotting strategy, when to use it, and how to interpret it. We then put these plots in action by revisiting two recent articles from Legislative Studies Quarterly.     

An investigation into the enhancement of fingermarks in blood on fruit and vegetables

A number of studies have reported the successful enhancement of latent fingermarks on fruit and vegetables. A study was set up to identify the most effective technique for the enhancement of fingermarks in blood on various fruit and vegetables. The enhancement techniques targeted different components in blood and consisted of protein stains (e.g. acid black 1), peroxidase reagents (e.g. leuco crystal violet) and amino acid stains (e.g. ninhydrin). Different variables such as the ageing periods of the marks and a diminishing series were employed to assess the suitability and sensitivity of the enhancement techniques.Overall, the use of different protein stains appeared to be the most effective techniques for the enhancement of fingermarks in blood on fruit and vegetables. In addition, the aubergine and cucumber skins appeared to be the most responsive surface to the different chemical techniques during enhancement. On the contrary, little or no enhancement was achieved for fingermarks in blood on the nectarine fruit.     

Identification of Different Forms of Cocaine and Substances Used in Adulteration Using Near‐infrared Raman Spectroscopy and Infrared Absorption Spectroscopy

Identification of cocaine and subsequent quantification immediately after seizure are problems for the police in developing countries such as Brazil. This work proposes a comparison between the Raman and FT‐IR techniques as methods to identify cocaine, the adulterants used to increase volume, and possible degradation products in samples seized by the police. Near‐infrared Raman spectra (785 nm excitation, 10 sec exposure time) and FT‐IR‐ATR spectra were obtained from different samples of street cocaine and some substances commonly used as adulterants. Freebase powder, hydrochloride powder, and crack rock can be distinguished by both Raman and FT‐IR spectroscopies, revealing differences in their chemical structure. Most of the samples showed characteristic peaks of degradation products such as benzoylecgonine and benzoic acid, and some presented evidence of adulteration with aluminum sulfate and sodium carbonate. Raman spectroscopy is better than FT‐IR for identifying benzoic acid and inorganic adulterants in cocaine.     

A fatal case of pepper poisoning.

An 8 month old infant died as the result of administration of a traditional remedy, given orally as an infusion of a red powder. The symptoms on admission were coughing with diarrhoea and vomiting. Analysis of the powder using high-performance liquid chromatography (HPLC) confirmed the suspicion of capsaicin. Pepper preparations, which are used as traditional medicines, are highly toxic and their use on infants should be discouraged.     

The discrimination potential of ultraviolet-visible spectrophotometry, thin layer chromatography, and Fourier transform infrared spectroscopy for the forensic analysis of black and blue ballpoint inks

The knowledge of the discriminating power of analytical techniques used for the differentiation of writing inks can be useful when interpreting results. Ultraviolet-visible (UV-VIS) spectrophotometry, thin layer chromatography (TLC), and diffuse reflectance Fourier transform infrared spectroscopy (FT-IR) were used to examine a population of 21 black and 12 blue ballpoint writing inks. Based on corroborative results of these methods, the discrimination power for UV-VIS, TLC, and FT-IR was determined to be 100% and 98% for the black and blue inks, respectively. Generally, TLC and UV-VIS can be used to differentiate the colorant components (i.e., dyes and some pigments) found in inks. As FT-IR can be utilized to identify some of the noncolorant components, it was determined to be an excellent complementary technique that can be implemented into an analytical scheme for ink analysis.     

Fingermark detection on non-porous and semi-porous surfaces using YVO4:Er,Yb luminescent upconverting particles

This article describes the use of an anti-Stokes luminescent material (upconverter), yttrium vanadate doped with ytterbium and erbium (YVO(4):Er,Yb), for the development of latent fingermarks on a range of non-porous surfaces. Anti-Stokes luminescent materials emit light at shorter wavelengths than the excitation wavelength. This property is unusual in both natural and artificial materials commonly found as exhibits in forensic science casework. As a result, fingermark detection techniques based on anti-Stokes luminescence are potentially extremely sensitive and selective. Latent fingermarks on non-luminescent and inherently luminescent substrates, including Australian polymer banknotes (a well-known 'difficult' surface), were developed with YVO(4):Er,Yb by dry powder and wet powder techniques. The effectiveness of YVO(4):Er,Yb for fingermark detection was compared with that of cyanoacrylate fuming and of sodium yttrium tetrafluoride doped with ytterbium and erbium (NaYF(4):Er,Yb). The results illustrate some benefit of luminescent up-converting phosphors over traditional luminescence techniques for the detection of latent fingermarks.     

Loose cannons: Covert commerce and underground finance in the modern arms black market

The 1990s have already witnessed an explosion of social and political violence, with the threat of much more on the way. Many explanations have been offered — the stripping of the constraints formerly imposed by the Cold War alliance system; the delegitimization of states and the resurgence of ethno-religious identification; the end of the post-War social consensus that promised (though often did not deliver) a modicum of distributive justice.The paper stresses another, more mundane explanation — namely, the triumph over efforts at control of a free market in the instruments for effecting social and political change by violent means. It explains the contradiction between the amount of human, social and political damage weapons do and the ease with which they are acquired by exploring structural changes in the world arms black market since the 1980s.First, it argues that existing data showing a sharp decrease in international arms transfers can be reinterpreted in a much more pessimistic way, in part because of the operation of the modern black market.Second, a definition is offered of a black market transaction, differentiating it from otherwise legitimate deals that are criminalized on either the supply or demand sides.Third, it notes dramatic changes in the nature of the demand for weapons that drives more buyers into the black market.Fourth, it examines changes on the supply side that have made it so easy for a black market participant to acquire weapons, whether for direct end-use or for resale.Fifth, broad structural changes in the machinery of black marketeering in general, and their applications to the arms market in particular, are outlined.Sixth, a profile of the modern, as distinct from the traditional, gun running profession is offered, stressing the ambiguous role of the intelligence services in the traffic.Seventh, a black market arms deal is traced in its various stages through the machinery of covert commerce, while exploring at each stage the implications for pricing.Eight, the return flow of money is analyzed, from the point of view both of the form in which payment is made and the role of the formal banking system in handling and laundering the flow.Ninth, the financial problems facing non-state buyers and the consequent role of unconventional currencies is examined.Finally, some observations are offered about the implications of recent developments in the arms market for issues of arms control and international security.