Black Coat Research Articles

Parliamentary Dress

Parliamentary Dress

Plasma Electrolytic Oxidation of Titanium in Ni and Cu Hydroxide Suspensions towards Preparation of Electrocatalysts for Urea Oxidation

The increasing climate crisis requires an improvement in renewable energy technologies. One of them are fuel cells, devices that are capable of generating electricity directly from the chemical reaction that is taking place inside of them. Despite the advantages of these solutions, a lack of the appropriate materials is holding them back from commercialization. This research shows preliminary results from a simple way to prepare black TiO2 coatings, doped with Cu or Ni using the plasma electrolytic oxidation process, which can be used as anodes in urea-fueled fuel cells. They show activity toward urea oxidation, with a maximum current density of 130 μA cm-2 (@1 V vs. Hg|HgO) observed for Cu-enhanced TiO2 and low potential of only 0.742 V (Vs Hg|HgO) required for 50 μA cm-2 for Ni-enhanced TiO2. These results demonstrate how the PEO process can be used for the preparation of TiO2-based doped materials with electrocatalytic properties toward urea electrooxidation.

Effects of chemical weathering on the exceptional preservation of mineralized insects from the Crato Formation, Cretaceous of Brazil: implications for late diagenesis of fine-grained Lagerstätten deposits

AbstractMany studies have improved our understanding of the mode of preservation at the Crato fossil Lagerstätte. The high degree of preservation of the Crato mineralized insects is thought to be a consequence of the diffusion of ions through carcasses and envelopment by bacteria that, in turn, created microenvironmental conditions that led to mineralization, mainly pyritization. Pyritized insects have been oxidized by in situ weathering to more stable oxide/hydroxy minerals during Quaternary time. This transformation is essential to maintain the palaeontological information acquired during microbially induced pyritization in an oxidizing atmosphere. However, intense weathering can diminish or obscure the morphological fidelity, and little attention has been paid to the post-diagenetic processes experienced by these fossils. Here, we aim to determine the degree of alteration undergone by Crato pyritized insects using the following combination of analytical tools: scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared and Raman spectroscopy. Our results show that well-preserved insects are preferentially replaced by haematite and poorly preserved fossils are replaced by goethite. In addition, we recorded three types of post-diagenetic alteration: insects with iron-oxide overgrowths; insects associated with black coatings, sometimes with the formation of dendrites; and insects preserved as an impression, where only the outline of the body remains. All of these alterations have the potential to distort or tarnish palaeontological information. Here, we measured the effects of such telodiagenetic alterations at macro and micro scales. Therefore, this taphonomic approach has wide applicability wherever fine-grained deposits bearing mineralized insects are found.

Structure and Properties of Black Ceramic MAO Coatings on Aluminum Alloys

The existing processes for obtaining black wear-resistant coatings include chemical methods, anodic oxidation followed by painting in aniline dyes, electrochemical deposition, vacuum plasma treatment, microarc oxidation (MAO). Of great interest for the formation of light-absorbing coatings is the MAO method, which is characterized as a reliable and environmentally friendly process, which provides the formation of a hard ceramic-like oxide layer with high corrosion resistance аnd good adhesion to the substrate. Therefore, the development of methods for obtaining high-quality black MAO coatings with both high optical and mechanical characteristics is currently an urgent task. The paper presents the results of a study of the structure and properties of black ceramic coatings on aluminum alloy AMg2 obtained by microarc oxidation using silicate-alkaline and silicate-phosphate electrolytes containing potassium ferrocyanide and sodium tungstate as coloring components. Sodium tungsten acid and potassium ferrocyanide with a concentration of 0.5 to 2.0 g/l were added to the electrolytes as additional components that ensured the coloring of the coatings. It has been established that the most saturated black coatings in a silicate-alkaline electrolyte are formed with the addition of 1.5–2.0 g/l of sodium tungstate, and in a silicate-phosphate electrolyte with the addition of 1.5 g/l of potassium ferrocyanide. The use of an electrolyte containing sodium tungstate makes it possible to form coatings with a lower microroughness height (Ra 0.97–1.11 µm) compared to coatings obtained in an electrolyte containing potassium ferrocyanide (Ra up to 4.20 µm). The maximum wear resistance of the resulting coatings (wear rate (0.38–0.59) × 10–4 mm3/(m×N)) is achieved by treatment in the studied electrolytes with a duration of 10 min. In this case, the thickness of the coatings is 21–31 µm. A further increase in the duration of processing does not have a significant effect on the wear rate.

A COMPARISON OF “THE BLACK COAT” AND “THE OVERCOAT”: SIGNIFYING THE PRIMAL ROLE OF WOMEN WRITERS IN THE RUSSIAN SHORT STORY TRADITION

This paper examines the paradigm shift in the genre of Russian horror short stories, and this tectonic shift is exemplified by a parallel reading of Nikolai Gogol’s “The Overcoat” and Ludmilla Petrushevskaya’s “The Black Coat”. The juxtaposition of these two stories exposes how male writers have always been placed on a pedestal in the Russian literary canon. In contrast, this paper highlights how the contributions of their female counterparts have been constantly sidelined, though both streams of works enriched the vast field of the Russian literary empire. Narratology theory is used to highlight the narrative techniques of both authors since it examines what narratives share and what makes them unique. This is illustrated by demonstrating how writers like Petrushevskya have dismantled the common notion that only male writers contribute to the technical aspects of a genre. Using the comparative methodology, this paper also traces the tradition of this genre and the holistic perspective towards the Russian women writers who outpoured their creative capacity, good enough to be recognised and appreciated. The conclusion of the paper discusses the way Ludmilla Petrushevskaya broke the former institution of short stories with a touch of psychic horror (female psyche) by going along with the characteristic features of Russian literature: the inner world of characters.

Selection signatures for local and regional adaptation in Chinese Mongolian horse breeds reveal candidate genes for hoof health

BackgroundThousands of years of natural and artificial selection since the domestication of the horse has shaped the distinctive genomes of Chinese Mongolian horse populations. Consequently, genomic signatures of selection can provide insights into the human-mediated selection history of specific traits and evolutionary adaptation to diverse environments. Here, we used genome-wide SNPs from five distinct Chinese Mongolian horse populations to identify genomic regions under selection for the population-specific traits, gait, black coat colour, and hoof quality. Other global breeds were used to identify regional-specific signatures of selection.ResultsWe first identified the most significant selection peak for the Wushen horse in the region on ECA23 harbouring DMRT3, the major gene for gait. We detected selection signatures encompassing several genes in the Baicha Iron Hoof horse that represent good biological candidates for hoof health, including the CSPG4, PEAK1, EXPH5, WWP2 and HAS3 genes. In addition, an analysis of regional subgroups (Asian compared to European) identified a single locus on ECA3 containing the ZFPM1 gene that is a marker of selection for the major domestication event leading to the DOM2 horse clade.ConclusionsGenomic variation at these loci in the Baicha Iron Hoof may be leveraged in other horse populations to identify animals with superior hoof health or those at risk of hoof-related pathologies. The overlap between the selection signature in Asian horses with the DOM2 selection peak raises questions about the nature of horse domestication events, which may have involved a prehistoric clade other than DOM2 that has not yet been identified.

Morphometric and morphological analysis of indigenous Matabele goats of Zimbabwe

This study aimed to characterize Matabele goats based on their qualitative and quantitative traits, to facilitate their genetic improvement and conservation. Data were collected from 120 goats over 12 months, comprising 20 males and 100 females using a stratified random sampling approach. Body weight and various body measurements were recorded. Five growth curve estimation models were employed to describe the growth pattern of Matabele goats. Descriptive statistics were computed for both qualitative and quantitative traits. T-tests were conducted to assess the impact of sex on morphometric measurements in different age groups. The results revealed an average body weight of 20.93 kg, with significant sex-related differences (p < 0.05) observed across all quantitative traits. Most goats displayed horned and bearded characteristics, while black and white coat colours were predominant. Among the growth curve models, the Gompertz model exhibited the highest R2 value (0.992). Notably, the study found relatively low average morphometric measurements and body weight for Matabele goats, emphasizing the urgent need for genetic improvement efforts and the development of comprehensive breeding standards for this breed.

B Flach! B Flach!

B Flach! B Flach!

BREEDING HERITAGE OF DAIRY CATTLE OF UKRAINE – UKRAINIAN WHITE-HEADED BREED

BREEDING HERITAGE OF DAIRY CATTLE OF UKRAINE – UKRAINIAN WHITE-HEADED BREED

Characterization of high absorbance and high-emissivity black Ni[sbnd]Ce oxide composite coatings produced via photo-assisted electrodeposition

Q235 steel, whose nominal composition (wt%) is 0.14–0.22 C, 0.30–0.65 Mn, ≤0.30 Si, ≤0.045 P, ≤0.055 S and Fe balance, has played an important role in the development of human history and the establishment of modern industry due to its excellent mechanical and engineering performance. In this study, black NiCe oxide composite coatings were electrodeposited on Q235 steel under photo-illumination and the effect of potential was studied. A 300 W ultra-high power xenon lamp with 300–2500 nm wavelength was the light source and provided 220,000 Lux irradiation intensity. After deposition of 40 min, black, uniform, and compact coatings were obtained; their colour gradually deepened when the potential changed from −0.7 to −0.9 V vs. saturated calomel electrode. The composite coatings improved the corrosion resistance of the substrate. Ni and Ce(III) content in the composite coating increased, whereas the hardness decreased at a more negative deposition potential. A black composite coating with both high absorptivity and high emissivity was obtained at a deposition potential of −0.8 V with photo-illumination, which exhibited an emissivity of 0.846 and absorptivity of approximately 95 % in the ultraviolet band, 90 % in the visible region, and 92 % in the near-infrared band. Exposure experiments showed that the absorptivity and emissivity decreased very little on exposing to a natural environment for one month. The electrodeposition mechanism and possible reasons for the above behavior are discussed in detail. The study provides an idea to prepare black coatings with high absorptivity and emissivity that are expected to be used in the naval, aerospace industry, photothermal conversion and optical instruments.

Preparation of black thermal control PEO coatings on TC4 with enhanced electrical conductivity by gas thermal penetration post-treatment

The black thermal control coating with enhanced conductivity was prepared by PEO and gas thermal penetration post-treatment with methanol as carbon source. The structure and composition of coatings were tested and analyzed by SEM, TEM, XRD, XPS and Raman spectroscopy. The as-prepared composite coatings (C-PEO coating) retained the typical porous characteristics and were mainly possessed polycrystalline structure. During the penetration treatment, the decomposition of methanol led to the increase of graphitization degree of amorphous carbon and the formation of a carbon conductive network in the coating, and partial high valence metal oxides were reduced to low valence in the reducing atmosphere. Gas thermal penetration post-treatment improved the conductivity of the coating was mainly attributed to the carbon conductive network. The PEO coating after penetration treatment at 700 °C for 3 h had the lowest volume resistivity of 2.63 × 103 Ω·m, which also remained high absorptivity (200–2500 nm, 0.947) and emissivity (2.5–16 μm, 0.917). After electron irradiation, the mass loss of the coating was 0.033 g·m−2, and the absorptivity and emissivity only decreased to 0.946 and 0.911, respectively, indicating excellent anti-electron irradiation ability. This work opens a new road to improve the conductivity of PEO coating.

FIRST REPORT AND DESCRIPTION OF MELANISM AND ALBINISM IN GIANT ANTEATER, Myrmecophaga tridactyla (XENARTHRA, MYRMECOPHAGIDAE)

Myrmecophaga tridactyla , the giant anteater, is a monospecific genus of anteater endemic to South and Central America. This species is marked by a predominantly brown or black coat, with anterolaterally elongated black and white stripes in its body and anterior black bands on its forelimbs. Chromatic variations are so far unknown for this species. Herein, we report and describe the first formal records of melanism and albinism in M. tridactyla and discuss the possible causes and environmental relationships of these color anomalies in the species.

Optical Interference Coating Design Contest 2022: a black box coating and a filter for an outdoor 3D cinema challenge [invited

The design problems for the Optical Interference Coating (OIC) 2022 Topical Meeting include black box coatings to reverse engineer and a pair of white-balanced, multi-bandpass filters for three-dimensional cinema projection in cold and hot outdoor environments. There were 14 designers from China, France, Germany, Japan, Russia, and the United States, submitting 32 total designs for problems A and B. The design problems and the submitted solutions are described and evaluated.

Genetic Diversity Relationship in Azakheli Buffalo Inferred from mtDNA and MC1R Sequences Comparison.

Azakheli is relatively smaller riverine breed with a very peculiar characteristics kept under unique traditional husbandry practices in comparison with rest of the Pakistani buffalo breeds; however, milk production is comparable. The present study was conducted to evaluate the genetic diversity of Azakheli breed. A total of sixty-six blood samples were collected for the amplification of mtDNA D-loop region and MC1R gene sequencing analysis. Median-joining network analysis of 191 mtDNA D-loop sequences of Azakheli and eight Indian riverine buffalo breeds clustered into three clades. Ancient Azakheli Region 1 clade was the oldest with the highest mutation steps and was present close to the root of UPGMA phylogenetic tree. There was 5 mutated lines distance between Pakistan buffalo and Indian riverine buffaloes. The populations of neighboring countries did not share any haplotypes with Azakheli buffalo of Pakistan. Possibly, residing for so long in the cold atmosphere and high elevation regions caused the mutation in mtDNA D-loop, though these conditions did not affect the overall performance of Azakheli as milch buffalo breed of Pakistan. MC1R analyses showed high mutations in Azakheli of Albino phenotype and all the black phenotype individuals of Azakheli buffalo share haplotypes with dominant Chinese and Indian black phenotypes buffaloes in MC1R median-joining network, indicating the reason of black coat color is due to MC1R gene. The haplotype diversity and nucleotide diversity was (H. 0.923, Pi: 0.00895) in Azakheli. Current results illustrated Asian ancestry for Azakheli buffalo, and mtDNA and MC1R analyses provided further evidence. Additional genetic analyses and archeological studies may provide further insight into the domestication period and history of Azakheli buffalo breed. The further studies are required on different coat colors with different genes on Azakheli buffalo to understand the phenotype variation.

Study on Microstructure and Properties of Black Micro-Arc Oxidation Coating on AZ31 Magnesium Alloy by Orthogonal Experiment.

The effects of CuSO4 concentration, voltage and treating time on the hemisphere emissivity and corrosion resistance of AZ31B magnesium-alloy black micro-arc oxidation coatings were studied by orthogonal experiment. The microstructure, phase composition, corrosion resistance and hemisphere emissivity of the coating were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, electrochemical test and infrared emissivity spectrometer, respectively. The results showed that the influences of each factor on corrosion current density and the hemisphere emissivity are as follows: voltage > treating time > CuSO4 concentration. The black MAO coatings are mainly composed of WO3, MgAl2O4, CuAl2O4, MgO, CuO and MgF2. The CuO and CuAl2O4 phases are the main reasons for blackness of the coatings. The coating exhibits the best corrosion resistance under the conditions of CuSO4 concentration 1.5 g/L, oxidation voltage 500 V and treating time 10 min. Additionally, the variation trends of hemispherical emissivity and roughness of the black MAO coating are the same when the composition of the coatings is similar. When the concentration of CuSO4 is 1.5 g/L, the oxidation voltage is 450 V and the treatment time is 10 min, the coating with the highest hemispherical emissivity of 0.84 can be obtained.

Influence of successive heat waves on the thermoregulatory responses of pregnant and non-pregnant ewes

The frequency of heat waves has increased over the last years, with an impact on animal production and health, including the death of animals. Therefore, the aim of this study was to evaluate the dynamics of thermoregulation and hormonal responses in non-pregnant and pregnant ewes exposed to successive heat waves. Twenty-four non-pregnant and 18 pregnant Santa Ines ewes with black coat color (live weight: 55 ± 9.03 kg; age: 60 months) were used. Weather variables such air temperature, relative humidity, and solar radiation were continuously recorded. The rectal and tympanic temperatures and respiratory rate were measured daily. Serum triiodothyronine (T3) and prolactin were evaluated during the heat wave and thermoneutral periods. The physiological variables were higher under the heat wave conditions and were related to the activation of the thermoregulatory system for maintaining homeothermy (P < 0.05). The core body temperature was higher during successive heat waves (P < 0.05), as was the tympanic temperature, which are both affected by changes in air temperature (P < 0.05). T3 and prolactin levels were not influenced by successive heat waves (P < 0.05) and rectal temperature and respiratory rate were highest in non-pregnant ewes (P < 0.05). Prolactin was not affected by temperature. The results indicate that the Santa Ines breed overcomes the thermal challenge during a heat wave without showing severe signs of thermal stress regardless of being pregnant or not.

Studies on the effect of the composition of wrought alloys (D16, AMg6 and V95) on the formation kinetics, structure, and electrochemical behavior of black plasma-electrolytic coatings

Studies on the effect of the composition of wrought alloys (D16, AMg6 and V95) on the formation kinetics, structure, and electrochemical behavior of black plasma-electrolytic coatings

Plasma electrolytic oxidation behavior and corrosion resistance of brass in aluminate electrolyte containing NaH2PO4 or Na2SiO3

Plasma electrolytic oxidation (PEO) of brass was carried out in aluminate electrolytes with the addition of NaH2PO4 (S1) and Na2SiO3 (S2), respectively, with the aim to investigate the effect of additives on the coating formation and corrosion resistance. For the PEO in S1 electrolyte, a mixed layer of AlPO4 and Al2O3 is formed at the initial stage, which leads to fast plasma discharges and formation of black coatings with the compositions of Al2O3, CuO, Cu2O and ZnO. However, in S2 electrolyte, plasma discharges are delayed and the coatings show a reddish color due to more Cu2O. Mott-Schottky tests show that the S1 coatings are p-type semiconductors; while the S2 coatings can be adjusted between n-type and p-type. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests show that the PEO treatment can significantly improve the corrosion resistance of brass, with protection efficiency up to 91.50% and the largest charge transfer resistance of 59.95 kΩ·cm2 for the S1 coating.

Black maternal health scholars on fire: Building a network for collaboration and activism.

Black maternal health scholars on fire: Building a network for collaboration and activism.

Oxidation of glucose to glycolic acid using oxygen and pyrolyzed spent Li-ion battery electrode material as catalyst

A search for non-noble catalysts for biomass processing led to the discovery that pyrolyzed electrode coating of spent Li-ion batteries can be used as an excellent catalyst for oxidation of D-glucose to glycolic acid. New no/low-cost catalyst was prepared by pyrolyzing black electrode coatings of 18,650 Li-ion cells from a spent DELL 1525 laptop battery at 600 ºC. Catalyst was characterized using SEM, EDX and X-ray and was shown to contain lithium nickel manganese cobalt oxide (LiaNibMncCodOe) on carbon with Ni: Mn: Co 4.12: 2.10: 1.50. The catalytic activity of this material was evaluated for oxidation of D-glucose in aq. NaOH and water; glycolic, tartaric, malic, succinic and 2-hydroxybutaric acid were identified as key degradation products. The highest glycolic acid yield of 94% was obtained for oxidation of D-glucose under 3.4 Atm. oxygen, 120 °C, 2.0 h in 0.5 M aq. NaOH using 10 g catalyst/mol glucose.