scholarly journals The diffusion of gases through metals III-The degassing of nickel and the diffusion of carbon monoxide through nickel.

Author(s):  
C. J. Smithells ◽  
C. E. Ransley ◽  
Ralph Howard Fowler

When a piece of metal prepared by a commercial process is heated for the first time in vacuo , a considerable amount of gas is usually evolved. With the more refractory metals like nickel or molybdenum, evacuation for a few minutes at 1000° C is sufficient to remove part only of gas present, and prolonged heating for many hours is necessary before the evolution ceases to be measurable. It may be assumed that some part at least of this gas is derived from the body of the metal and must presumably reach the surface by diffusion. The total gas is extracted much more rapidly if the metal is actually melted, and this method of estimating the gases in steel and other metals has been very generally adopted. The fact that the evolution of gases from metals on heating depends upon a process of diffusion from the interior to the surface of the metal, and subsequent evaporation, has been established for the simple gases. The desorption of nitrogen from molybdenum, and of hydrogen from hydrogen-charged nickel has been shown to follow theoretical equations derived from Fick's diffusion law. In practice, the gases obtained from commercial metals often contain a large proportion of compound gases, particularly the oxides of carbon, but very little information is available on the diffusion of such gases through metals.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shreeya Sriram ◽  
Shitij Avlani ◽  
Matthew P. Ward ◽  
Shreyas Sen

AbstractContinuous multi-channel monitoring of biopotential signals is vital in understanding the body as a whole, facilitating accurate models and predictions in neural research. The current state of the art in wireless technologies for untethered biopotential recordings rely on radiative electromagnetic (EM) fields. In such transmissions, only a small fraction of this energy is received since the EM fields are widely radiated resulting in lossy inefficient systems. Using the body as a communication medium (similar to a ’wire’) allows for the containment of the energy within the body, yielding order(s) of magnitude lower energy than radiative EM communication. In this work, we introduce Animal Body Communication (ABC), which utilizes the concept of using the body as a medium into the domain of untethered animal biopotential recording. This work, for the first time, develops the theory and models for animal body communication circuitry and channel loss. Using this theoretical model, a sub-inch$$^3$$ 3 [1″ × 1″ × 0.4″], custom-designed sensor node is built using off the shelf components which is capable of sensing and transmitting biopotential signals, through the body of the rat at significantly lower powers compared to traditional wireless transmissions. In-vivo experimental analysis proves that ABC successfully transmits acquired electrocardiogram (EKG) signals through the body with correlation $$>99\%$$ > 99 % when compared to traditional wireless communication modalities, with a 50$$\times$$ × reduction in power consumption.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Caleb Liang ◽  
Wen-Hsiang Lin ◽  
Tai-Yuan Chang ◽  
Chi-Hong Chen ◽  
Chen-Wei Wu ◽  
...  

AbstractBody ownership concerns what it is like to feel a body part or a full body as mine, and has become a prominent area of study. We propose that there is a closely related type of bodily self-consciousness largely neglected by researchers—experiential ownership. It refers to the sense that I am the one who is having a conscious experience. Are body ownership and experiential ownership actually the same phenomenon or are they genuinely different? In our experiments, the participant watched a rubber hand or someone else’s body from the first-person perspective and was touched either synchronously or asynchronously. The main findings: (1) The sense of body ownership was hindered in the asynchronous conditions of both the body-part and the full-body experiments. However, a strong sense of experiential ownership was observed in those conditions. (2) We found the opposite when the participants’ responses were measured after tactile stimulations had ceased for 5 s. In the synchronous conditions of another set of body-part and full-body experiments, only experiential ownership was blocked but not body ownership. These results demonstrate for the first time the double dissociation between body ownership and experiential ownership. Experiential ownership is indeed a distinct type of bodily self-consciousness.


Author(s):  
Gemma Almond

Abstract This study explores the representation and use of Victorian visual aids, specifically focusing on how the design of spectacle and eyeglass frames shaped ideas of the ‘normal’ and ‘abnormal’ body. It contributes to our understanding of assistive technologies in the Victorian period by showcasing the usefulness of material evidence for exploring how an object was produced and perceived. By placing visual aids in their medical and cultural context for the first time, it will show how the study of spectacle and eyeglass frames develops our understanding of Victorian society more broadly. Contemporaries drew upon industrialization, increasing education, and the proliferation of print to explain a rise in refractive vision ‘errors’. Through exploring the design of three spectacle frames from the London Science Museum’s collections, this study will show how the representations and manufacture of visual aids transformed in response to these wider changes. The material evidence, as well as contemporary newspapers, periodicals, and medical texts, reveal that visual aids evolved from an unusual to a more mainstream device. It argues that visual aids are a unique assistive technology, one that is able to inform our understanding of how Victorians measured the body and constructed ideas of ‘normalcy’ and ‘abnormalcy’.


2001 ◽  
Vol 79 (3) ◽  
pp. 263-271
Author(s):  
Paul K Baker ◽  
Michael GB Drew ◽  
Deborah S Evans

Reaction of [WI2(CO)3(NCMe)2] with two equivalents of 1-phenyl-1-propyne (MeC2Ph) in CH2Cl2, and in the absence of light, gave the bis(1-phenyl-1-propyne) complex [WI2(CO)(NCMe)(η2-MeC2Ph)2] (1) in 77% yield. Treatment of equimolar quantities of 1 and NCR (R = Et, i-Pr, t-Bu, Ph) in CH2Cl2 afforded the nitrile-exchanged products, [WI2(CO)(NCR)(η2-MeC2Ph)2] (2-5) (R = Et (2), i-Pr (3), t-Bu (4), Ph (5)). Complexes 1, 2, and 5 were structurally characterized by X-ray crystallography. All three structures have the same pseudo-octahedral geometry, with the equatorial sites being occupied by cis and parallel alkyne groups, which are trans to the cis-iodo groups. The trans carbon monoxide and acetonitrile ligands occupy the axial sites. In structures 1 and 2, the methyl and phenyl substituents of the 1-phenyl-1-propyne ligands are cis to each other, whereas for the bulkier NCPh complex (5), the methyl and phenyl groups are trans to one another. This is the first time that this arrangement has been observed in the solid state in bis(alkyne) complexes of this type.Key words: bis(1-phenyl-1-propyne), carbonyl, nitrile, diiodo, tungsten(II), crystal structures.


2011 ◽  
Vol 170 ◽  
pp. 165-169 ◽  
Author(s):  
Tahir Ali ◽  
Ernst Bauer ◽  
Gerfried Hilscher ◽  
Herwig Michor

We report on structural and superconducting properties of La3-xRxNi2B2N3- where La is substituted by the magnetic rare-earth elements Ce, Pr, Nd. The compounds Pr3Ni2B2N3- and Nd3Ni2B2N3- are characterized for the first time. Powder X-ray diffraction confirmed all samples R3Ni2B2N3- with R = La, Ce, Pr, Nd and their solid solutions to crystallize in the body centered tetragonal La3Ni2B2N3 structure type. Superconducting and magnetic properties of La3-xRxNi2B2N3- were studied by resistivity, specific heat and susceptibility measurements. While La3Ni2B2N3- has a superconducting transition temperature Tc ~ 14 K, substitution of La by Ce, Pr, and Nd leads to magnetic pair breaking and, thus, to a gradual suppression of superconductivity. Pr3Ni2B2N3- exibits no long range magnetic order down to 2 K, Nd3Ni2B2N3- shows ferrimagnetic ordering below TC =17 K and a spin reorientation transition to a nearly antiferromagnetic state at 10 K.


1970 ◽  
Vol 48 (19) ◽  
pp. 2265-2271 ◽  
Author(s):  
A. Anderson ◽  
T. S. Sun ◽  
M. C. A. Donkersloot

The Raman spectra of polycrystalline α-nitrogen and α-carbon monoxide have been recorded at 18 °K, using argon–ion and helium–neon laser excitation. Previously undetected peaks at 60 cm−1 for N2 and 90.5 cm−1 for CO are assigned as librational modes, and splitting of the stretching mode in nitrogen is observed for the first time. Spectral features in both the intramolecular and lattice regions are assigned in accordance with accepted crystal structures, and their frequencies compared with those obtained from calculations based on a spherical Lennard–Jones potential and quadrupole–quadrupole interactions between the molecules.


2021 ◽  
Vol 12 (4) ◽  
Author(s):  
B. V. Borysevych ◽  
◽  
V. V. Lisova ◽  
I. M. Derkach ◽  
S. S. Derkach ◽  
...  

Iron (IV) clathrochelate based on a macrobicyclic ligand of the hexahydrazide type is a unique compound that contains iron in a rare high valence IV. Preclinical and clinical studies of this complex, which were started for the first time in Ukraine, have an important theoretical and practical consequence as this complex can be recommended as an active substance in iron-containing drugs with antianemic action. In conducting preclinical studies of new drugs, pathomorphological studies are important because they are a necessary step in studying the biological response of animals to the action of test substances. It was found that some pathological changes develop in the body of white mice under conditions of experimental acute and chronic iron (IV) clathrochelate intoxication. They correlated with the dose of the test compound. During chronic intoxication, the microscopic changes in the liver and kidney of white mice treated with iron (IV) clathrochelate at a dose of 1/10 DL50 were similar to the microscopic changes in the liver and kidney of mice treated with the experimental drug at a dose of 1/5 DL50. However, the severity of these changes was lower, reflecting a lower degree of organ damage. In the myocardium of mice treated with iron (IV) clathrochelate at a dose of 1/5 DL50 on the 10th day, as in acute iron (IV) clathrochelate poisoning, only edema was recorded. The prospects for further research are the study of microscopic changes in the organs of laboratory animals of other species during experimental iron (IV) clathrochelate toxicosis.


Author(s):  
Beschasnyi S.P. ◽  
Lysenko E.M. ◽  
Hasiuk O.M. ◽  
Erlish О.О.

Carbon monoxide is a toxic gas that is colourless, odourless, and has the potential to cause momentaryhypoxia by bonding with heme-inspired proteins. Because of these properties, it causes the highest number of toxications. Due to its properties, this gas causes damage to the nervous and cardiovascular system. The development of anoxia is associated with the impact on the system of oxidative phosphorylation in mitochondria and the development of oxidative stress in the body. The body produces a small amount of carbon monoxide as a result of erythrocyte breakdown. Picomolar concentrations of carbon monoxide even have anti-inflammatory, antiapoptotic,cytoprotective and antiproliferative properties. Kidney is one of the first organs,that responds to the occurrence of hypoxia, are responsible for the removal of products of metabolism and toxicants, including ethanol. For the study, the blood and urine samples were taken from patients with acute intoxication. The amount of methemoglobin in the blood was determined by spectrophotometric method. The concentration of ethanol in blood and urine was measured by gas-liquid chromatography method. The correlation analysis showed that carbon monoxide affects the rate of excretion of ethanol from the body. Among individuals under 40 years of age, there was a correlation between the level of carbon monoxide and the amount of ethanol in the blood. Among older adults this correlation was not established. A direct correlation with the level of this gas in the blood and the level of ethanol in the urine among people under 40 years of age was found. Among older individuals, the opposite was observed –a high level of methemoglobin was responsible for the decreased level of ethanol. There were no correlations between methemoglobin level and age. Comparison of the studied indices did not show any sexual differences in ethanol excretion, but there were age specific features: ethanol excretion under the influence of carbon monoxide among people under 40 years old was more accelerated.Key words:hypoxia, CO intoxication, blood, methemoglobin, kidneys. Монооксид карбону являє собою токсичний газ, який не має кольору,без запаху та здатен спричиняти миттєву гіпоксію шляхом зв’язування з гем-вмісними білками. Через такі властивості він спричиняє найбільшу кількість отруєнь. Цей газ,завдяки своїм властивостям,спричиняє ураження нервової та серцево-судинної системи. Розвиток аноксії пов’язаний із впливом на систему окисного фосфорилювання у мітохондріях та розвиткомоксидативного стресу. В організмі продукується невелика кількість ендогенного монооксиду карбону внаслідок розпаду еритроцитів. Пікомолярні концентрації монооксиду карбону навіть володіють протизапальними, антиапоптичними, цитопротекторними та антипроліферативними властивостями. Нирки є одним із перших органів, який реагує на розвитокгіпоксії, вони відповідають за видалення продуктів метаболізму й токсикантів, зокрема етанолу.Зміни у функціонуванні нирок відображаються на загальному стані організму.Для дослідження отримували зразки крові та сечі від осіб із гострою інтоксикацією. У крові спектрофотометричним методом визначали вміст метгемоглобіну, який утворювався внаслідок вдихання монооксиду карбону та відповідного потрапляння до кровоносної системи. Методом газово-рідинної хроматографії вимірювали концентрацію етанолу у крові та сечі. Розрахунок кореляційних зв’язків показав, що монооксид карбону впливає на швидкість екскреції етанолу. У осіб до 40 років спостерігалася кореляція між показником рівня метгемоглобінута вмістом етанолу у крові. У осіб старшого віку цього зв’язку не встановлено. Виявлено прямий зв’язок із рівнем цього газу у крові та рівнем етанолу в сечі у осіб до 40 років. У осіб старшого віку спостерігалася зворотня реакція–високий рівень метгемоглобінуобумовлював зниження рівня етанолу. Кореляційні зв’язки між вмістом метгемоглобіну та віком не було виявлено. Порівняння досліджуваних показників не виявило статевих відмінностей у екскреції етанолу, проте виявлено вікові особливості: екскреція етанолу в умовах впливу монооксиду карбону в осіб до 40 років була більш пришвидшена.Таким чином, можна стверджувати, що монооксид карбону обумовлює зміни у функціональній активності нирок.Ключові слова:гіпоксія, інтоксикація СО, кров, метгемоглобін, нирки.


Author(s):  
Abou-eisha A ◽  
Adel E El-din

Objective: The aim of this study was to investigate, for the first time, the possible in vivo genotoxic and carcinogenic activity associated with exposure to norgestrel (NGT) drug through employing the very recently established and adjusted genotoxic and tumorigenic methods in Drosophila melanogaster.Methods: Two in vivo genotoxic test systems were used; one detects the somatic mutation and recombination effects (somatic mutation and recombination test [SMART] wing-spot test) and the other detects the primary DNA damage (the comet test) in the body cells of D. melanogaster. On the other hand, the warts (wts)-based SMART assay is a vital genetic examination in Drosophila used to identify and characterize cancer potential of compounds.Results: Four experimental doses of NGT were used (ranging from 0.24 μM to 16 μM). NGT was found to be non-genotoxic at all tested concentrations even at the highest dose level 16 μM and failed to increase the frequency of tumors in the somatic cells of D. melanogaster.Conclusion: Our results strengthen the hypothesis that steroidal drugs might act through a non-genotoxic carcinogen mechanism where the carcinogenic properties occur by direct stimulation of cellular proliferation through a steroid receptor-mediated mechanism. In addition, the results obtained in this research work may contribute to highlighting the importance of NGT as a potent neuroprotective antioxidant drug.


2018 ◽  
Vol 63 (4) ◽  
pp. 835-838 ◽  
Author(s):  
Roser Adalid ◽  
Jordi Torres ◽  
Marcos Miñarro ◽  
Màrius Vicent Fuentes ◽  
Jordi Miquel

Abstract The Ityogonimus lorum-I. ocreatus co-infection is reported for the first time in the Iberian mole Talpa occidentalis in Asturias (NW Spain). Both Ityogonimus species are stenoxenous helminths of insectivores of the genus Talpa and they have often been found parasitizing the Iberian mole and also the European mole T. europaea, but a mixed infection had not been previously reported. The present study also highlights the main differential morphometric characteristics between I. lorum and I. ocreatus such as the body length, the ventral sucker diameter, the ratio between suckers and the distance between suckers.


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