The Law of Physico-Chemical Change

1901 ◽  
Vol 37 (3) ◽  
pp. 49 ◽  
Author(s):  
Gilbert Newton Lewis
Keyword(s):  
Chemical Change ◽  
Physico Chemical ◽  
The Law

scholarly journals Croonian lecture.—Observations on isolated nerve. Electrical changes a measure of physico-chemical change

1896 ◽  
Vol 59 (353-358) ◽  
pp. 308-312
Keyword(s):  
Chemical Change ◽  
Physico Chemical ◽  
Chemical Conditions

The present investigation arises from experiments undertaken to determine autographically the varying relations between the magnitude of electrical change and the magnitude of stimulation in nerve under various chemical conditions.

scholarly journals A Physico-chemical Change of Dissolving Pulp by Dry Milling and Fractionation

2015 ◽  
Vol 47 (5) ◽  
pp. 23-32
Author(s):  
Taeyoung Kim ◽  
Songmin Lee ◽  
Yongdae Heo ◽  
Jinyoung Kim ◽  
Yangjin Joung
Keyword(s):  
Chemical Change ◽  
Dissolving Pulp ◽  
Dry Milling ◽  
Physico Chemical

Aging effects on the physico-chemical change of asphalt and mixture performance

2020 ◽  
Vol 22 (2) ◽  
pp. 23-31
Author(s):  
Beak Woon Lee ◽  
Eui Yoon Hwang ◽  
Hosono Hiroki ◽  
Hiramatsu Makoto
Keyword(s):  
Chemical Change ◽  
Aging Effects ◽  
Physico Chemical

scholarly journals A study of catalytic actions at solid surfaces. Part XII.—Some observations relative to those particles of a catalyst which participate in chemical change

1925 ◽  
Vol 108 (745) ◽  
pp. 111-120 ◽  
Keyword(s):  
Experimental Evidence ◽  
Chemical Change ◽  
Nickel Atom ◽  
Solid Surfaces ◽  
Catalytic Surface ◽  
Single Constraint ◽  
Physico Chemical ◽  
The Moment

The publication of Taylor’s theory of the catalytic surface renders it opportune to describe certain hitherto unpublished experiments which accord excellently with the view which he has advanced. Therefore, we give a brief outline of the work in question and adduce other experimental evidence which points to the strong probability that the acting (nickel) atom is, at the moment when catalytic change occurs, not merely held to the rest of the solid surfaces by a single constraint, but can be actually, momentarily, detached therefrom; in physico-chemical parlance, it has become for the time being a gaseous (nickel) atom.

scholarly journals The decomposition of ozone by heat

1908 ◽  
Vol 80 (539) ◽  
pp. 353-369 ◽  
Keyword(s):  
Chemical Change ◽  
Mass Action ◽  
Pressure Measurements ◽  
Law Of Mass Action ◽  
The Subject ◽  
Gas Reactions ◽  
The Law

Much doubt has recently existed as to the interpretation which may be put upon measurements of the velocity of chemical change in gas reactions. Van’t Hoff deduced the “order of the reaction” in certain cases from considerations of the law of mass action. Bone and Wheeler have shown that the combination of hydrogen and oxygen at temperatures below that necessary to explode the mixture takes place mostly (if not entirely) at the surfaces with which the gases are in contact, and that no conclusion as to the order of the reaction can be drawn from pressure measurements. Ozone was chosen for further work on the subject, as it affords one of the simplest possible cases. The decomposition by heat furnishes only one substance, and the reaction is irreversible (at least for all practical purposes).

scholarly journals Impact of mixing and chemical change on ozone-tracer relations in the polar vortex

2005 ◽  
Vol 5 (4) ◽  
pp. 5841-5874 ◽  
Author(s):  
R. Müller ◽  
S. Tilmes ◽  
P. Konopka ◽  
J.-U. Grooß ◽  
H.-J. Jost
Keyword(s):  
Chemical Change ◽  
Three Dimensional ◽  
Polar Vortex ◽  
Transport Processes ◽  
Lagrangian Model ◽  
Substantial Impact ◽  
Ozone Loss ◽  
Internal Mixing ◽  
Physico Chemical ◽  
Long Time

Abstract. Tracer-tracer relations have been used for a long time to separate physico-chemical change from change caused by transport processes. In particular, for more than a decade, ozone-tracer relations have been used to quantify chemical ozone loss in the polar vortex. The application of ozone-tracer relations for quantifying ozone loss relies on two hypotheses; that a compact ozone-tracer relation is established in the 'early' polar vortex and that any change of the ozone-tracer relation in the vortex over the course of winter is caused predominantly by chemical ozone loss. Here, we revisit this issue analysing various sets of measurements and the results from several models. We find that mixing across the polar vortex edge impacts ozone-tracer relations in a way that may solely lead to an ''underestimation'' of chemical ozone loss and not to an overestimation. Further, differential descent in the vortex and internal mixing has only a negligible impact on ozone loss estimates. Moreover, the representation of mixing in three-dimensional atmospheric models can have a substantial impact on the development of tracer relations in the model. Rather compact ozone-tracer relations develop – in agreement with observations – in the vortex of a Lagrangian model (CLaMS) where mixing is anisotropic and driven by the deformation of the flow. We conclude that, if a reliable 'early vortex' reference can be obtained and if vortex measurements are separated from mid-latitude measurements, ozone-tracer relations constitute a reliable tool for the quantitative determination of chemical ozone loss in the polar vortex.

scholarly journals Change in physico-chemical properties of soil and nutrients in Desmodium triflorum in case of seasonal variation in Ratnanagar-11, Jirauna, Chitwan, Nepal

2017 ◽  
Vol 3 (11) ◽  
pp. 285
Author(s):  
Niroj Paudel ◽  
Lila Pati Paudel ◽  
Prakash Deep Rai ◽  
Bishnu Dev Das
Keyword(s):  
Seasonal Variation ◽  
Rainy Season ◽  
Chemical Change ◽  
Winter Season ◽  
Chemical Properties ◽  
Low Ph ◽  
Physico Chemical ◽  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus ◽  
Properties Of Soil

<p class="abstract"><strong>Background:</strong> Physico-chemical change is described in case of seasonal variation. The plant became grazed in different seasonings; nitrogen, phosphorus and potassium are estimated. The aim of paper is the nutrient uptake of <em>Desmodium triflorum due</em> to the change in season.</p><p class="abstract"><strong>Methods:</strong> The sample is collected as four month interval period the grass is tolerate as low pH<strong>. </strong>N-1.67–2.04%, P- 0.34–0.61% and K-1.46–4.15%.  </p><p class="abstract"><strong>Results:</strong> Soil had lowest concentrations of nitrogen (0.096%), phosphorus (0.004%), and potassium (0.027%) in the rainy season. The highest concentration of nitrogen (0.22%) occurred in summer season, phosphorus (0.005%) in winter and summer seasons, and potassium (0.073%) in the winter season. The carbon/nitrogen (C/N) ratio was highest (15.22:1) in summer and lowest (13.96:1) in the rainy season.</p><p><strong>Conclusions:</strong> Present study will be valuable in evaluation and management of the middle land pastures in Nepal.</p>

I. The conditions of chemical change in gases: hydrogen, carbonic oxide, and oxygen

1884 ◽  
Vol 37 (232-234) ◽  
pp. 56-61 ◽  
Keyword(s):  
Nitrous Oxide ◽  
Carbonic Acid ◽  
Chemical Change ◽  
Incomplete Combustion ◽  
Whole Numbers ◽  
Relative Affinity ◽  
The Law ◽  
Combustible Gases

Bunsen, in 1852, exploded mixtures of carbonic oxide and electrolytic gas in different proportions in order to test the correctness of the “Law of Mass.” According to this law the division of oxygen between two combustible gases depends both on the relative affinity of the two combustibles for oxygen, and on the quantities of them present. In 1857 Bunsen published some further experiments on the same subject. He concluded from his results that the Law of Mass was modified in a particular way by the tendency of the atoms to form simple hydrates of carbonic acid; so that the ratio of carbonic oxide to hydrogen might be changed within certain limits without altering the proportion in which the oxygen divides itself; but, on still further changing the ratio of carbonic oxide to hydrogen, the proportion in which the oxygen divides itself changes per saltum . The ratio between the carbonic acid and the stream produced in the explosion might always be expressed, according to Bunsen, by small integers. In 1874 E. v. Meyer published experiments on the incomplete combustion of mixtures of carbonic oxide and hydrogen by oxygen and by nitrous oxide. He concluded that the division of the oxygen between the combustible gases changes per saltum , and that the ratio between the carbonic acid and steam produced might always be expressed by whole numbers, hut not always by small integers.

scholarly journals Low–temperature sensors in bacteria

2002 ◽  
Vol 357 (1423) ◽  
pp. 887-893 ◽  
Author(s):  
Sofia Eriksson ◽  
Reini Hurme ◽  
Mikael Rhen
Keyword(s):  
Low Temperature ◽  
Chemical Change ◽  
Temperature Sensors ◽  
Bacterial Virulence ◽  
Structural Alterations ◽  
Sensory Event ◽  
Physico Chemical ◽  
Gene Response ◽  
Regulatory Cascades ◽  
Main Factor

Bacteria are ubiquitous colonizers of various environments and host organisms, and they are therefore often subjected to drastic temperature alterations. Temperature alterations set demands on these colonizers, in that the bacteria need to readjust their biochemical constitution and physiology in order to survive and resume growth at the new temperature. Furthermore, temperature alteration is also a main factor determining the expression or repression of bacterial virulence functions. To cope with temperature variation, bacteria have devices for sensing temperature alterations and a means of translating this sensory event into a pragmatic gene response. While such regulatory cascades may ultimately be complicated, it appears that they contain primary sensor machinery at the top of the cascade. The functional core of such machinery is usually that of a temperature–induced conformational or physico–chemical change in the central constituents of the cell. In a sense, a bacterium can use structural alterations in its biomolecules as the primary thermometers or thermostats.

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