scholarly journals Bakerian lecture.—On the law of the pressure of gases between 75 and 150 millimetres of mercury

1902 ◽  
Vol 69 (451-458) ◽  
pp. 495-495
Keyword(s):  
Mercury Column ◽  
In Series ◽  
The Law ◽  
Low Pressures

The observations here recorded were intended to bridge over in some degree the gap between the very low pressures (below 1·5 mm.) dealt with in a recent paper and pressures approaching the atmospheric for which the usual mercury column and cathetometer method is adequate. The principal novelty consists in the use of two similar manometric gauges. Pressures in the ratio of 1 : 2 are obtained by the use first of a single gauge and secondly of the two gauges connected in series.

scholarly journals IX. Bakerian Lecture .—On the law of the pressure of gases between 75 and 150 millimetres of mercury

1902 ◽  
Vol 198 (300-311) ◽  
pp. 417-430 ◽  
Keyword(s):  
Pressure Chamber ◽  
Present Communication ◽  
In Series ◽  
Experimental Errors ◽  
The Law ◽  
Open Question ◽  
High Degree ◽  
Low Pressures ◽  
Published Paper ◽  
Boyle’S Law

In a recently published paper I have examined, with the aid of a new manometer, the behaviour of gases at very low pressures, rising to 1·5 millims. of mercury, with the result that Boyle’s law was verified to a high degree of precision. There is, however, a great gap between the highest pressure there dealt with and that of the atmosphere—a gap which it appeared desirable in some way to bridge over. The sloping manometer, described in the paper referred to, does not lend itself well to the use of much greater pressures, at least if we desire to secure the higher proportional accuracy that should accompany the rise of pressure. The present communication gives the results of observations, by another method, of the law of pressure in gases between 75 millims. and 150 millims. of mercury. It will be seen that for air and hydrogen Boyle’s law is verified to the utmost. In the case of oxygen, the agreement is rather less satisfactory, and the accordance of separate observations is less close. But even here the departure from Boyle’s law amounts only to one part in 4000, and may perhaps be referred to some reaction between the gas and the mercury. In the case of argon too the deviation, though very small, seems to lie beyond the limits of experimental errors. Whether it is due to a real minute departure from Boyle’s law, or to some complication arising out of the conditions of experiment, must remain an open question. In the case of pressures not greatly below atmosphere, the determination with the usual column of mercury read by a cathetometer (after Regnault) is sufficiently accurate. But when the pressure falls to say one-tenth of an atmosphere, the difficulties of this method begin to increase. The guiding idea in the present investigation has been the avoidance of such difficulties by the use of manometric gauges combined in a special manner. The object is to test whether when the volume of a gas is halved its pressure is doubled, and its attainment requires two gauges indicating pressures which are in the ratio of 2:1. To this end we may employ a pair of independent gauges as nearly as possible similar to one another, the similarity being tested by combination in parallel, to borrow an electrical term. When connected below with one reservoir of air and above with another reservoir, or with a vacuum, the two gauges should reach their settings simultaneously, or at least so nearly that a suitable correction may be readily applied. For brevity we may for the present assume precise similarity. If now the two gauges be combined in series , so that the low-pressure chamber of the first communicates with the high-pressure chamber of the second, the combination constitutes a gauge suitable for measuring a doubled pressure.

scholarly journals On the absorption of water by cotton and wool

1907 ◽  
Vol 79 (529) ◽  
pp. 204-205 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Water Vapour ◽  
Air Temperature ◽  
Amorphous Carbon ◽  
The Law ◽  
Relationship Of ◽  
Low Pressures ◽  
The Relationship ◽  
System Water ◽  
Mechanical Rigidity

In a footnote to my paper entitled “ The Law of Distribution where one of the Phases possesses Mechanical Rigidity," I attempted to show how the results obtained by Professor Trouton for the absorption of water vapour by cotton could be reconciled with those obtained by me in the case of similar systems, such as carbon dioxide and amorphous carbon. As the apparatus I had employed in the investigation referred to was particularly suited to the accurate measurement of low pressures, I obtained Professor Trouton’s permission to repeat his work, and to investigate the relationship of pressure and concentration for the systems water-cotton and water-wool at the temperature of melting ice. I was particularly anxious to redetermine the lower portions of the curves, for as in Professor Trouton’s experiments the material was dried at the air temperature, it appeared probable that it contained water at the commencement of the experiment, and that the true origin of his curves lay further to the left than the results appeared to show. If this were the case, the true curve representing equilibrium in the system water-cotton might closely resemble those representing equilibrium in the system carbon dioxide and amorphous carbon.

scholarly journals On the excitation of the band spectrum of helium

1925 ◽  
Vol 109 (750) ◽  
pp. 267-272 ◽  
Keyword(s):  
Discharge Tube ◽  
High Current Density ◽  
Band Spectrum ◽  
Essential Condition ◽  
Spark Gap ◽  
In Series ◽  
Pure Helium ◽  
Faint Band ◽  
The Individual ◽  
Low Pressures

It is now generally agreed that the band spectrum of helium, which was first observed by Curtis (‘Roy. Soc. Proc.,’ A, vol. 89, p. 146, 1913) and by Goldstein (‘Verh. d. Deutsch. Phys. Gesell.,’ vol. 15, p. 402, 1913), is to be attributed to some molecule of helium. This band spectrum is peculiar in the fact that the heads of the bands have been shown by Fowler (‘Rov. Soc. Proc.,’ A, vol. 91, p. 208, 1915) to follow the law usually associated with line spectra, though the individual lines composing the bands can be represented by the parabolic arrangement appropriate to band series. More recently, Curtis has carried out a series of investigations (‘Roy. Soc. Proc.’) on the structure of the bands in terms of the quantum theory. Attention may here be drawn to two peculiarities in the spectrum. There is one isolated band with a head at about λ = 5733 A., which is degraded to the violet, whilst all the remaining bands are degraded to the red. Also Goldstein ( loc. cit. ) observed a number of faint band lines in the region about λ = 5390 A. to λ = 5270 A., which were not recorded in Curtis’s paper ( loc. cit .). It is well known that in vacuum tubes excited by uncondensed discharges only faint traces of the principal band heads are visible in the positive column though the complete band spectrum appears in the negative glow. The band spectrum can be excited with much greater intrinsic brightness by using a discharge tube with a wide tube in place of the usual capillary, and exciting it by means of a discharge from an induction coil or transformer, with a condenser in parallel and a small spark gap in series with the discharge tube, the band spectrum under these conditions appearing throughout the tube. There appears to be an optimum length of spark gap and the spectrum tends to become weaker when the length is increased beyond a certain point. Curtis ( loc. cit .) has found that the band spectrum is not strongly developed at low pressures, and this condition appears to be independent of other conditions of excitation. In the present investigation we have found that under certain conditions the band spectrum can be greatly modified. It was observed that when a vacuum tube, containing pure helium, which had been made with the capillary in several sections of different bore, was excited with an uncondensed discharge the narrowest section, which was of the finest thermometer tubing that could be worked conveniently in the blowpipe, showed nothing but the line spectrum, but in the wider sections on either side the band spectrum was quite strongly developed. This seems to show that a high-current density is not an essential condition for the excitation of the band spectrum, but it was remarkable that with these tubes it appeared in the wider parts, where it would not have been seen if the capillaries had not been provided with a section of narrow bore.

Coronavirus Disease (COVID-19) Identification Time Analysis Using Queueing Model (Preprint)

2020 ◽  
Author(s):  
Vladimiras Dolgopolovas
Keyword(s):  
Law Of Iterated Logarithm ◽  
General Tendency ◽  
Time Analysis ◽  
Identification Process ◽  
Iterated Logarithm ◽  
Detection And Identification ◽  
In Series ◽  
Queues In Series ◽  
The Law ◽  
Evaluation Parameters

BACKGROUND The article presents an application of a model of queues in series queueing system under overloading conditions to estimate the time of detection and identification of coronavirus (COVID-19) infections. OBJECTIVE The objective is to present a simplified probabilistic model for assessing the general tendency to estimate the period of time needed to detect and identify already infected citizens before the treatment process really begins. METHODS The law of the iterated logarithm is proved for such a system, which shows that the general identification process corresponds to the law of iterated logarithm. RESULTS Some numerical examples of a different number of evaluation parameters are provided. CONCLUSIONS The modelling results showed that the sojourn time of the patient in the process of coronavirus investigation/detection/identification and treatment in the case of imbalance in the system as a whole increase in accordance with the law of the iterated logarithm. Even if the process of the treatment phases is well arranged and generally balanced, in case of the rate of investigation/detection/identification is lower than the rate of infection, the total number of already infected and unidentified citizens will increase in accordance with the law of the iterated logarithm.

scholarly journals Isotherms of CO 2 between 0° and 150° and pressures from 16 to 250 atm (Amagat densities 18-206)

1935 ◽  
Vol 153 (878) ◽  
pp. 201-214 ◽  
Keyword(s):  
Dielectric Constant ◽  
Platinum Wire ◽  
Pressure Balance ◽  
Large Reservoir ◽  
Equilibrium Pressure ◽  
Steel Vessel ◽  
Mercury Surface ◽  
Mercury Column ◽  
In Series ◽  
Balance Corrections

In a previous publication* results of measurements were given of the dielectric constant of CO 2 under pressure. In the calculation of the Clausius-Mosotti function, ε-1/ε+2. 1/ d , from these results and the isotherm data as published by Amagat doubt arose as to the reliability of the latter, and isotherrn measurements have therefore been carried out up to 3000 atm at the same temperature at which the dielectric constant was measured. The results will be given in series of papers, of which the present one describes the measurements up to 250 atm. In this range the method published in previous papers could be used. The apparatus is shown diagrammatically in fig. 1. A is the glass piezometer containing the gas under investigation. It is enclosed in the steel vessel C, which contains some mercury, the remainder being filled with oil. The piezometer consists of a large reservoir B and several small reservoirs connected by narrow capillaries. Through each of these capillaries is sealed a platinum wire, and these all make contact with another platinum wire wound round the outside of the capillary and connected to an insulated lead E through the top of the steel vessel. The volumes from each of the contact to the top of the tube are calibrated by weighing with mercury, using the method described by Michels and Gibson. The volume of gas with which the piezometer is filled is determined separately at 25° and a pressure of about 1 atm, as described by Michels, Wouters, and de Boer. The steel vessel is placed in a thermostat, the temperature of which is electrically regulated in the way previously described by the authors. The temperature is read with thermometers divided in hundredths of a degree and compared with thermometers calibrated at the P. T. R. (Berlin). They were totally immersed in the thermostat and read with the help of a periscope. For the isotherm measurements, pressure is applied to the oil through D, forcing the mercury up inside the piezometer and compressing the gas till the mercury surface makes contact with the platinum wires. This contact is indicated by a drop in the electrical resistance of the platinum wire wound round the capillary. The equilibrium pressure, at which contact is made, is measured with a pressure balance. Corrections must be applied for the height of the mercury column inside the glass piezometer and the hydrostatic head of the oil. From the data thus obtained for p, v , and T, the isotherm can be calculated if the total amount of gas contained in the piezometer is known in standard units.

scholarly journals Hukum Boikot Barangan Israel Berdasarkan kepada Fiqh Al-Jihad

2018 ◽  
Vol 4 (1) ◽  
pp. 135-160
Author(s):  
Anas Mohd Yunus ◽  
Najihah Abd Wahid ◽  
Wan Saifuldin Wan Hassan
Keyword(s):  
Qualitative Research ◽  
Content Analysis ◽  
Reference Method ◽  
Primary Method ◽  
Analysis Method ◽  
Financial Investment ◽  
Content Analysis Method ◽  
In Series ◽  
The Law

This study is to determine the law to the boycott of Israeli goods based on the discipline of jihad fi sabilillah. The boycott of Israeli goods is a campaign to avoid purchasing particular goods from the producers that support the Zionist Regime through their financial, investment and moral. It is driven by the Muslims to support the Palestinian people and protest the Zionist Regime who killed Palestinians and confiscated their lands, especially in series of intifada by Palestinian and the attacks on Gaza. This study evaluates the boycott’s law from the perspective of Fiqh al-Jihad and looking into the changes between fard ain and fard kifayah influenced by certain factors and conditions. This is due to the confusion among people about the jihad in Palestine, especially when involving the boycott. Thus, an enlightenment on the issue is very important to be evaluated scientifically. The study employed qualitative research using documentary reference method as the primary method. The data were analyzed using content analysis method by applying Usul Fiqh as the basis of the discussion while referring to the debates of the existing fiqh (jurisprudence). The results showed that in general, the law to the boycott of Israeli products and those who support them become fard ain on every Muslim. Keywords : Boycott, Palestine, jihad, fard ain, fard kifayah Abstrak Kajian ini adalah untuk menentukan hukum boikot barangan Israel berdasarkan kepada disiplin jihad fi sabilillah. Boikot barangan Israel merupakan satu kempen pemulauan pembelian barangan khususnya ke atas barangan pengeluar-pengeluar yang menyokong rejim Zionis Israel melalui sokongan dana, pelaburan dan moral. Ia digerakkan oleh umat Islam untuk memberikan sokongan kepada rakyat Palestin dan membantah perbuatan rejim Zionis yang membunuh rakyat Palestin dan merampas tanah-tanah mereka terutamanya dalam siri-siri intifadah dan serangan ke atas Gaza. Kajian ini menilai hukum boikot daripada perspektif fiqh al-jihad dan melihat perubahan-perubahan hukum fardu ain dan fardu kifayah berikutan faktor-faktor keadaan dan tempat. Ini berikutan berlaku kekeliruan terhadap kedudukan jihad di Palestin khususnya yang melibatkan boikot. Justeru, satu pencerahan berkaitan isu ini amat penting untuk dinilai secara ilmiah. Kajian berbentuk kualitatif dengan menggunakan kaedah rujukan dokumen sebagai kaedah utama. Data dianalisis menggunakan kaedah analisis kandungan dengan mengaplikasikan kaedah usul fiqh sebagai teras utama di samping merujuk kepada perbahasan-perbahasan fiqh yang sedia ada. Hasil kajian menunjukkan secara umumnya, hukum boikot barangan Israel dan pendukung-pendukungnya menjadi fardu ain ke atas setiap umat Islam. Kata kunci : Boikot, Palestin, jihad, fardu ain, fardu kifayah

scholarly journals On experiments relating to the spectrum of nitrogen

1925 ◽  
Vol 107 (743) ◽  
pp. 411-422 ◽  
Keyword(s):  
Nitrogen Atom ◽  
Atmospheric Pressure ◽  
Negative Band ◽  
Discharge Tubes ◽  
In Series ◽  
Striking Change ◽  
The Subject ◽  
Band Spectra ◽  
Low Pressures ◽  
Conventional Type

It is somewhat remarkable that the spectrum of the neutral nitrogen atom, nitrogen arc or NI spectrum, should be the least known of the spectra associated with nitrogen. The positive and negative band spectra, associated with nitrogen molecules, have been the subject of many investigations, and the line spectra which are developed when condensed discharges are passed rough nitrogen at atmospheric pressure or through nitrogen contained in ancuum tubes, the spectrum of singly ionised nitrogen, the NII spectrum, has recently been arranged in series by Fowler ( ‘Roy. Soc. Proc.,' vol. 107, A, p. 31,25), who has in an earlier investigation (‘Monthly Notices R. A. S.,’ vol. 80, 692, 1920) assigned a number of lines which have not yet been arranged in series to the doubly ionised nitrogen atom. It would appear that under ordinary conditions of excitation the lines of the arc or nitrogen I spectrum are not conspicuous, and we are indebted to Hardtke (‘Ann. der Phys.,’ vol. 3, p. 363, 1918) for the information at present available with respect to this Spectrum. Hardtke found that with discharge tubes of special construction containing nitrogen a number of lines were predominant in the spectrum of the positive rays observed in certain regions of the discharge tubes, and that the same lines were relatively enhanced in vacuum tubes of the conventional type when they were excited by condensed discharges of feeble moderate intensities. Hardtke gave approximate measurements of a Number of these lines, which he assigned to the arc spectrum. In a series of previous investigations (Merton, ‘ Roy. Soc. Proc.,’ A, vol. 96, 382, 1920; Merton and Barratt, ‘ Phil. Trans.,’ A, vol. 222, p. 369, 1922; Merton and Johnson, ‘ Roy. Soc. Proc.,’ A, vol. 103. p. 383, 1923) it has been Shown that profound modifications are sometimes observed in the spectrum of a substance when a very small quantity of that substance is present in a discharge tube containing helium at a comparatively high pressure, and the tube is excited by condensed or uncondensed discharges. Thus with uncondensed discharges there is a striking change in the distribution of intensity the lines of the secondary spectrum of hydrogen; a trace of carbon is recognised by the appearance of the ‘‘comet tail” spectrum, first observed by Fowler (‘Monthly Notices R. A. S.,’ vol. 70, p. 484, 1910) at very low pressures and when both carbon and hydrogen are present a new triplet series of band: are developed.

scholarly journals On the laws governing electric discharges in gases at low pressures

1903 ◽  
Vol 71 (467-476) ◽  
pp. 374-376 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Electric Field ◽  
Potential Difference ◽  
Electric Discharges ◽  
Wide Range ◽  
Apparatus 3 ◽  
The Law ◽  
Low Pressures ◽  
Different Gases

The experiments described in this paper were undertaken with the object of determining the potential difference required to produce discharge in a number of gases over a wide range of pressures, and especially of ascertaining if the law enunciated by Paschen was generally applicable, provided the electric field in which the discharge took place was uniform. The paper is divided into the following sections :— (1.) Introduction. (2.) Description of apparatus. (3.) Experiments in air. (4.) Experiments in hydrogen. (5.) Experiments in carbon dioxide. (6.) Spark potentials with different electrodes. (7.) Minimum spark potentials. (8.) Connection between spark lengths and spark potentials. (9.) Minimum spark potentials in different gases. (10.) Summary of results.

The Shikani HME: A New Tracheostomy Heat and Moisture Exchanger

2020 ◽  
Vol 63 (9) ◽  
pp. 2921-2929
Author(s):  
Alan H. Shikani ◽  
Elamin M. Elamin ◽  
Andrew C. Miller
Keyword(s):  
Ex Vivo ◽  
Moisture Loss ◽  
Speaking Valve ◽  
Time Zero ◽  
In Series ◽  
Turbulent Airflow ◽  
The Difference ◽  
Loss Efficiency ◽  
Heat And Moisture ◽  
Lung Simulation

Purpose Tracheostomy patients face many adversities including loss of phonation and essential airway functions including air filtering, warming, and humidification. Heat and moisture exchangers (HMEs) facilitate humidification and filtering of inspired air. The Shikani HME (S-HME) is a novel turbulent airflow HME that may be used in-line with the Shikani Speaking Valve (SSV), allowing for uniquely preserved phonation during humidification. The aims of this study were to (a) compare the airflow resistance ( R airflow ) and humidification efficiency of the S-HME and the Mallinckrodt Tracheolife II tracheostomy HME (M-HME) when dry (time zero) and wet (after 24 hr) and (b) determine if in-line application of the S-HME with a tracheostomy speaking valve significantly increases R airflow over a tracheostomy speaking valve alone (whether SSV or Passy Muir Valve [PMV]). Method A prospective observational ex vivo study was conducted using a pneumotachometer lung simulation unit to measure airflow ( Q ) amplitude and R airflow , as indicated by a pressure drop ( P Drop ) across the device (S-HME, M-HME, SSV + S-HME, and PMV). Additionally, P Drop was studied for the S-HME and M-HME when dry at time zero (T 0 ) and after 24 hr of moisture testing (T 24 ) at Q of 0.5, 1, and 1.5 L/s. Results R airflow was significantly less for the S-HME than M-HME (T 0 and T 24 ). R airflow of the SSV + S-HME in series did not significant increase R airflow over the SSV or PMV alone. Moisture loss efficiency trended toward greater efficiency for the S-HME; however, the difference was not statistically significant. Conclusions The turbulent flow S-HME provides heat and moisture exchange with similar or greater efficacy than the widely used laminar airflow M-HME, but with significantly lower resistance. The S-HME also allows the innovative advantage of in-line use with the SSV, hence allowing concurrent humidification and phonation during application, without having to manipulate either device.

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