scholarly journals The Influence of the Humidity of the Air on Capacity for Work at High Temperatures

1932 ◽  
Vol 32 (3) ◽  
pp. 431-462 ◽  
Author(s):  
H. M. Vernon ◽  
C. G. Warner
Keyword(s):  
Pulse Rate ◽  
Effective Temperature ◽  
Temperature Scale ◽  
Mechanical Efficiency ◽  
The Body ◽  
London School ◽  
Moist Air ◽  
Dry Air ◽  
The Face ◽  
Made In

The physiological reactions of two subjects were investigated in air at a temperature of 70–100° F., and of 40–96 per cent. relative humidity. The experiments lasted 3 hours, and one of the subjects performed mechanical work (step climbing) at the rate of 14,000 kg. m. per hour.The pulse rate was about 10 beats greater in dry air than in moist air of the same wet-bulb temperature. The winter observations agreed well with the effective temperature scale, but did not agree with the wet bulb, the dry-bulb or the kata-thermometer scales.Acclimatisation effects showed themselves in experiments made at a dry-bulb temperature of 87° F. or more, but only very slightly in those made at 81° or less. Acclimatisation was fairly well marked in the summer, the pulse rate being 5 to 10 beats less than in the winter, and no longer agreeing with the effective temperature scale.The body temperature corresponded with the pulse rate, for it was 0·3–0·6° F. higher in dry air than in moist air of the same wet-bulb temperature, and was 0·15° lower in summer than in winter. The winter observations agreed well with the effective temperature scale.The skin temperature of the face was found to depend on the dry-bulb temperature of the air, but that of the trunk showed no agreement with any of the scales. In moist air it was 1° F. lower than that of the face, and in dry air, 6° lower, owing to the cooling effect of increased sweating.The gross mechanical efficiency fell off slightly at temperatures above 70 or 75° F. It was affected by the dry-bulb temperature of the air as well as the wet bulb, but not to the extent indicated by the effective temperature scale.The weight of moisture lost by sweating corresponded well with the effective temperature scale. It increased gradually in consecutive experiments made in dry air, and diminished in those made in moist air.The degree of fatigue experienced in dry air was considerably greater than in moist air of the same wet-bulb temperature, and it corresponded with the effective temperature scale.Acknowledgments. We wish, to express our indebtedness to the authorities at the London School of Hygiene and Tropical Medicine, and especially to Dr G. P. Crowden, for the facilities offered to us in our work.

XXI. The direct influence of gradual variations of temperature upon the rate of beat of the dog’s heart

1883 ◽  
Vol 174 ◽  
pp. 663-688 ◽  
Keyword(s):  
Arterial Pressure ◽  
Pulse Rate ◽  
Venous Pressure ◽  
Practical Importance ◽  
The Body ◽  
Full Account ◽  
Heart Beating ◽  
External Conditions ◽  
Work Done ◽  
Made In

In the year 1881 I briefly described (1) a method of experimenting by which the heart and lungs of a Dog or Cat could be completely isolated physiologically from the remainder of the body of the animal, and kept alive some hours for study in an apparently normal condition, the heart beating regularly and maintaining a good arterial pressure. Since then I have been at work investigating the influence of various conditions upon the pulse-rate of Dogs’ hearts so isolated; while under my supervision several of my pupils have been engaged in studying the work done in a unit of time by such hearts under different external conditions. As regards the effects of variations of arterial pressure upon the pulse-rate of the isolated Dog’s heart, my results have already been published (2); and detailed observations as to the influence of variations in venous pressure will shortly be printed. But in so far as the influence of temperature variations upon the cardiac rhythm is concerned, only a brief preliminary announcement (3) has been made. In the present paper I propose to give a full account of my experiments upon this subject, which is one that, apart from and in addition to its purely physiological interest, has considerable practical importance in connexion with inquiries as to the immediate cause of the quick pulse so constantly found in warm-blooded animals suffering from fever.

scholarly journals The Temperature and Humidity Relations of the cockroach

1936 ◽  
Vol 13 (1) ◽  
pp. 28-34
Author(s):  
DONALD L. GUNN ◽  
F. B. NOTLEY
Keyword(s):  
Body Temperature ◽  
The Body ◽  
Moist Air ◽  
Dry Air ◽  
Thermal Death ◽  
Temperature And Humidity ◽  
Ecological Importance

1. The thermal death-points of three species of cockroaches in dry and in moist air have been determined for 1-day and 1-hour exposures. 2. Moist air is more favourable than dry in the longer exposures, because in dry air death occurs from desiccation when the temperature itself is not fatal. 3. Dry air is more favourable than moist in the shorter exposures, owing to the fact that the evaporation of water lowers the body temperature. 4. Bearing in mind the thermotactic behaviour of these animals, these observations would seem to have little ecological importance.

A study of interface sliding at F.C.C.-B.C.C. boundaries in a Cu-Zn alloy

1978 ◽  
Vol 36 (1) ◽  
pp. 422-423
Author(s):  
F. Monchoux ◽  
A. Rocher ◽  
J.L. Martin
Keyword(s):  
Face Centered Cubic ◽  
Creep Tests ◽  
High Voltage Electron Microscopy ◽  
Diffusion Treatment ◽  
Voltage Electron ◽  
The Face ◽  
Face Centered ◽  
Interface Sliding ◽  
Zn Alloy ◽  
Made In

Interphase sliding is an important phenomenon of high temperature plasticity. In order to study the microstructural changes associated with it, as well as its influence on the strain rate dependence on stress and temperature, plane boundaries were obtained by welding together two polycrystals of Cu-Zn alloys having the face centered cubic and body centered cubic structures respectively following the procedure described in (1). These specimens were then deformed in shear along the interface on a creep machine (2) at the same temperature as that of the diffusion treatment so as to avoid any precipitation. The present paper reports observations by conventional and high voltage electron microscopy of the microstructure of both phases, in the vicinity of the phase boundary, after different creep tests corresponding to various deformation conditions.Foils were cut by spark machining out of the bulk samples, 0.2 mm thick. They were then electropolished down to 0.1 mm, after which a hole with thin edges was made in an area including the boundary

Pengoptimalan Air Leri dalam Pembuatan Sabun Pembersih Wajah Alami yang Ekonomis

2017 ◽  
Vol 3 (1) ◽  
Author(s):  
Rahmawati Rahmawati ◽  
Trimayasari Trimayasari ◽  
Ghozali Akhmad Mustaqim ◽  
Wening Dwi Prastiwi ◽  
Emas Agus Prastyo Wibowo
Keyword(s):  
Amino Acids ◽  
Fine Particles ◽  
Hard Water ◽  
Essential Amino Acids ◽  
Ultraviolet Rays ◽  
Starch Granules ◽  
Facial Skin ◽  
Skin Cells ◽  
The Face ◽  
Made In

AbstractSoap facial cleanser is needed to keep the facial skin to keep them clean and healthy. The purpose of this study to make soap cleanser with natural materials such as hard water deposits leri. This is because the use of leri water starch or starch granules of fine particles contained in water leri dansel dust can shed the dead skin on the face because of the essential amino acids contained can regenerate skin cells. In addition, water leri can brighten the face because the leri water oryzanol contain substances that can update the development and formation of the pigment melanin, which is effectively to ward off ultraviolet rays. The process of making soap using the principle of saponification reaction, namely the reaction between the oil and the KOH/NaOH. Facial cleansing soap made in this study is solid soap. Based on the results of quality test, soap solid leri water has a pH of 11.1, saponification number is 33, the water content of 46% as well as respondents to the test aspects of aroma and foam shows good results so this water leri treatment can be an alternative solution to prevent the use of soap facial cleansers that contain harmful chemicals. Keywords: air leri, soap cleanser, saponification  AbstrakSabun pembersih wajah sangat diperlukan untuk menjaga kulit wajah agar tetap bersih dan sehat. Tujuan dari penelitian ini untuk membuat sabun pembersih wajah dengan bahan alami berupa endapan air leri. Penggunaan air leri ini dikarenakan butiran partikel starch atau pati halus yang terdapat dalam air leri dapat merontokkan debu dansel kulit mati pada wajah karena asam amino esensial yang terkandung dapat meregenerasi sel-sel kulit. Selain itu, air leri dapat mencerahkan wajah karena air leri mengandung zat oryzanol yang dapat memperbarui perkembangan dan pembentukan pigmen melanin, yang efektif guna menangkal sinar ultraviolet. Proses pembuatan sabun menggunakan prinsip reaksi saponifikasi, yaitu reaksi antara minyak dan KOH/NaOH. Sabun pembersih wajah yang dibuat dalam penelitian ini ialah sabun padat. Berdasarkan hasil uji mutu, sabun air leri padat memiliki pH 11,1, angka penyabunan sebesar 33 kadar air 46 kadar air 46 % serta uji responden terhadap aspek aroma dan busa yang menunjukkan hasil cukup baik sehingga pengolahan air leri ini dapat menjadi solusi alternative untuk mencegah penggunaan sabun pembersih wajah yang mengandung bahan kimia berbahaya. Kata kunci: air leri, sabun pembersih wajah, saponifikasi 

Questions on the role of biofilms for the adaptation of microorganisms to unfavorable environmental factors by the example of P. aeruginosa

2020 ◽  
Vol 99 (4) ◽  
pp. 379-383
Author(s):  
Vasily N. Afonyushkin ◽  
N. A. Donchenko ◽  
Ju. N. Kozlova ◽  
N. A. Davidova ◽  
V. Yu. Koptev ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Environmental Factors ◽  
Barrier Function ◽  
Infectious Agent ◽  
Antagonistic Activity ◽  
The Body ◽  
Main Function ◽  
Pathogenic Potential ◽  
The Face

Pseudomonas aeruginosa is a widely represented species of bacteria possessing of a pathogenic potential. This infectious agent is causing wound infections, fibrotic cystitis, fibrosing pneumonia, bacterial sepsis, etc. The microorganism is highly resistant to antiseptics, disinfectants, immune system responses of the body. The responses of a quorum sense of this kind of bacteria ensure the inclusion of many pathogenicity factors. The analysis of the scientific literature made it possible to formulate four questions concerning the role of biofilms for the adaptation of P. aeruginosa to adverse environmental factors: Is another person appears to be predominantly of a source an etiological agent or the source of P. aeruginosa infection in the environment? Does the formation of biofilms influence on the antibiotic resistance? How the antagonistic activity of microorganisms is realized in biofilm form? What is the main function of biofilms in the functioning of bacteria? A hypothesis has been put forward the effect of biofilms on the increase of antibiotic resistance of bacteria and, in particular, P. aeruginosa to be secondary in charcter. It is more likely a biofilmboth to fulfill the function of storing nutrients and provide topical competition in the face of food scarcity. In connection with the incompatibility of the molecular radii of most antibiotics and pores in biofilm, biofilm is doubtful to be capable of performing a barrier function for protecting against antibiotics. However, with respect to antibodies and immunocompetent cells, the barrier function is beyond doubt. The biofilm is more likely to fulfill the function of storing nutrients and providing topical competition in conditions of scarcity of food resources.

Introduction

2018 ◽  
Author(s):  
Nora Goldschmidt ◽  
Barbara Graziosi
Keyword(s):  
Material Culture ◽  
The Body ◽  
Specific Site ◽  
Entire Volume ◽  
The Third ◽  
Religious Significance ◽  
Classical Poetry ◽  
Life Of The Mind ◽  
The Mind ◽  
Made In

The Introduction sheds light on the reception of classical poetry by focusing on the materiality of the poets’ bodies and their tombs. It outlines four sets of issues, or commonplaces, that govern the organization of the entire volume. The first concerns the opposition between literature and material culture, the life of the mind vs the apprehensions of the body—which fails to acknowledge that poetry emerges from and is attended to by the mortal body. The second concerns the religious significance of the tomb and its location in a mythical landscape which is shaped, in part, by poetry. The third investigates the literary graveyard as a place where poets’ bodies and poetic corpora are collected. Finally, the alleged ‘tomb of Virgil’ provides a specific site where the major claims made in this volume can be most easily be tested.

scholarly journals Post-Plasma Catalysis for Trichloroethylene Abatement with Ce-Doped Birnessite Downstream DC Corona Discharge Reactor

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 946
Author(s):  
Grêce Abdallah ◽  
Jean-Marc Giraudon ◽  
Rim Bitar ◽  
Nathalie De Geyter ◽  
Rino Morent ◽  
...  
Keyword(s):  
Corona Discharge ◽  
Active Oxygen Species ◽  
Surface Acidity ◽  
Good Stability ◽  
Ozone Decomposition ◽  
Moist Air ◽  
Plasma Catalysis ◽  
Dry Air ◽  
Water Tolerance ◽  
By Products

Trichloroethylene (TCE) removal was investigated in a post-plasma catalysis (PPC) configuration in nearly dry air (RH = 0.7%) and moist air (RH = 15%), using, for non-thermal plasma (NTP), a 10-pin-to-plate negative DC corona discharge and, for PPC, Ce0.01Mn as a catalyst, calcined at 400 °C (Ce0.01Mn-400) or treated with nitric acid (Ce0.01Mn-AT). One of the key points was to take advantage of the ozone emitted from NTP as a potential source of active oxygen species for further oxidation, at a very low temperature (100 °C), of untreated TCE and of potential gaseous hazardous by-products from the NTP. The plasma-assisted Ce0.01Mn-AT catalyst presented the best CO2 yield in dry air, with minimization of the formation of gaseous chlorinated by-products. This result was attributed to the high level of oxygen vacancies with a higher amount of Mn3+, improved specific surface area and strong surface acidity. These features also allow the promotion of ozone decomposition efficiency. Both catalysts exhibited good stability towards chlorine. Ce0.01Mn-AT tested in moist air (RH = 15%) showed good stability as a function of time, indicating good water tolerance also.

Transport properties of real moist air, dry air, steam, and water

2021 ◽  
pp. 1-9
Author(s):  
Sebastian Herrmann ◽  
Hans-Joachim Kretzschmar ◽  
Vikrant C. Aute ◽  
Donald P. Gatley ◽  
Eckhard Vogel
Keyword(s):  
Transport Properties ◽  
Moist Air ◽  
Dry Air

scholarly journals A Study of Moist Air Condensation Characteristics in a Transonic Flow System

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 4052
Author(s):  
Jie Wang ◽  
Hongfang Gu
Keyword(s):  
Mach Number ◽  
Relative Humidity ◽  
Transonic Flow ◽  
Flow System ◽  
Plane Surface ◽  
Droplet Growth ◽  
Moist Air ◽  
Dry Air ◽  
Hydraulic Equipment ◽  
Non Equilibrium

When water vapor in moist air reaches supersaturation in a transonic flow system, non-equilibrium condensation forms a large number of droplets which may adversely affect the operation of some thermal-hydraulic equipment. For a better understanding of this non-equilibrium condensing phenomenon, a numerical model is applied to analyze moist air condensation in a transonic flow system by using the theory of nucleation and droplet growth. The Benson model is adopted to correct the liquid-plane surface tension equation for realistic results. The results show that the distributions of pressure, temperature and Mach number in moist air are significantly different from those in dry air. The dry air model exaggerates the Mach number by 19% and reduces both the pressure and the temperature by 34% at the nozzle exit as compared with the moist air model. At a Laval nozzle, for example, the nucleation rate, droplet number and condensation rate increase significantly with increasing relative humidity. The results also reveal the fact that the number of condensate droplets increases rapidly when moist air reaches 60% relative humidity. These findings provide a fundamental approach to account for the effect of condensate droplet formation on moist gas in a transonic flow system.

scholarly journals Non-destructive handheld XRF study of archaeological composite silver objects—the case study of the late Roman Seuso Treasure

2021 ◽  
Vol 13 (5) ◽  
Author(s):  
Viktória Mozgai ◽  
Bernadett Bajnóczi ◽  
Zoltán May ◽  
Zsolt Mráv
Keyword(s):  
Fluorescence Analysis ◽  
The Body ◽  
High Quality ◽  
X Ray ◽  
Composite Objects ◽  
Mechanical Attachment ◽  
Non Destructive ◽  
Made In ◽  
Late Roman

AbstractThis study details the non-destructive chemical analysis of composite silver objects (ewers, situlas, amphora and casket) from one of the most significant late Roman finds, the Seuso Treasure. The Seuso Treasure consists of fourteen large silver vessels that were made in the fourth–early fifth centuries AD and used for dining during festive banquets and for washing and beautification. The measurements were systematically performed along a pre-designed grid at several points using handheld X-ray fluorescence analysis. The results demonstrate that all the objects were made from high-quality silver (above 90 wt% Ag), with the exception of the base of the Geometric Ewer B. Copper was added intentionally to improve the mechanical properties of soft silver. The gold and lead content of the objects shows constant values (less than 1 wt% Au and Pb). The chemical composition as well as the Bi/Pb ratio suggests that the parts of the composite objects were manufactured from different silver ingots. The ewers were constructed in two ways: (i) the base and the body were made separately, or (ii) the ewer was raised from a single silver sheet. The composite objects were assembled using three methods: (i) mechanical attachment; (ii) low-temperature, lead-tin soft solders; or (iii) high-temperature, copper-silver hard solders. Additionally, two types of gilding were revealed by the XRF analysis, one with remnants of mercury, i.e. fire-gilding, and another type without remnants of mercury, presumably diffusion bonding.

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