scholarly journals THE RELATION BETWEEN CHLOROPHYLL CONTENT AND RATE OF PHOTOSYNTHESIS

1935 ◽  
Vol 18 (4) ◽  
pp. 573-597 ◽  
Author(s):  
Walter E. Fleischer
Keyword(s):  
Chlorophyll Content ◽  
Similar Data ◽  
Straight Line Passing ◽  
Iron Supply ◽  
Similar Relation ◽  
Straight Line ◽  
Rate Of Photosynthesis ◽  
Line Passing

1. Data are presented which support the conclusion of Emerson (1929) that the rate of photosynthesis is proportional to the chlorophyll content when the latter is varied by varying the iron supply. These data give a straight line passing through the origin, which is not true of Emerson's results. 2. Similar data are presented which show that a similar relation exists when nitrogen controls the chlorophyll content. 3. Evidence is given which indicates that magnesium plays a part in the process of photosynthesis in addition to its effect upon the chlorophyll content.

scholarly journals Physical properties of surfaces. II—Viscous flow of liquid films. The range of action of surface forces

1935 ◽  
Vol 151 (872) ◽  
pp. 220-233 ◽  
Author(s):  
S. H. Bastow ◽  
Frank Philip Bowden ◽  
Thomas Martin Lowry
Keyword(s):  
Viscous Flow ◽  
Freezing Point ◽  
Applied Pressure ◽  
Liquid Films ◽  
Appreciable Effect ◽  
Straight Line Passing ◽  
Straight Line ◽  
Fluid Properties ◽  
Line Passing ◽  
Induced Structure

The present paper describes experiments which were carried out in order to determine the extent to which the fluid properties of water and other liquids may be modified by the presence of a solid surface. For this purpose, measurements of the viscous flow of a liquid very near to a surface are particularly suitable, since they provide a sensitive test for the existence of any induced structure in the liquid. If the surface has no appreciable effect, the smallest applied pressure will cause the liquid to flow and the rate of flow plotted against pressure will give a straight line passing through the origin, see fig. 3. If, however, as many authors have suggested, long chains of oriented liquid molecules with a definite rigidity are formed by the influence of the surface, the liquid will show a resistance to shear, which will be specially evident at low pressures; Poiseuille’s law will not hold and the pressure-flow curve will be of the form shown in fig. 4. A method has been developed for measuring the viscosity of thin liquid films enclosed between flat polished surfaces of glass and steel. The film thickness can be varied from about 10 -5 cm to any desired distance and can be accurately determined. The experiments show that films of a liquid, known to possess a bulk structure (liquid crystal), possess a high rigidity, but there is no sign of induced structure in normal liquids even with very thin films and at temperatures near the freezing point.

Spinor-Based Attitude Determination with Star Sensor Considering Depth

2021 ◽  
Vol 87 (8) ◽  
pp. 551-556
Author(s):  
Qinghong Sheng ◽  
Rui Ren ◽  
Weilan Xu ◽  
Hui Xiao ◽  
Bo Wang ◽  
...  
Keyword(s):  
Attitude Determination ◽  
Geometric Condition ◽  
Depth Information ◽  
Star Sensor ◽  
Imaging Geometry ◽  
Straight Line Passing ◽  
Geometry Model ◽  
Straight Line ◽  
Order Of Magnitude ◽  
Line Passing

A star sensor is a high-precision satellite attitude measurement device. Since its observation information has only two-dimensional direction vectors, when a star sensor is used for attitude determination the dimension of the observation information is less than the number of attitude angles determined, so mainstream algorithms usually only guarantee the accuracy of the pitch angle and the roll angle. In view of the lack of depth information in the observation's imaging geometric condition, this article proposes a spinor-based attitude determination model, which describes a straight line passing through two stars with the spinor and maps the depth information of the straight line with the pitch, to establish an imaging geometry model of the spinor coplanar condition. Experiments show that the yaw-angle attitude accuracy of the method is an order of magnitude better than that of mainstream algorithms, and the accuracy of the three attitude angles reaches the arc-second level.

scholarly journals A mathematical model of odor dispersion from a wastewater treatment plant

2019 ◽  
Vol 138 ◽  
pp. 01029
Author(s):  
Valerii Azarov ◽  
Tat’yana Solov’eva ◽  
Sergei Svitskov
Keyword(s):  
Mathematical Model ◽  
Wind Direction ◽  
Treatment Plant ◽  
Straight Line Passing ◽  
Straight Line ◽  
Odor Character ◽  
Line Passing ◽  
Kaliningrad Region ◽  
Odor Dispersion

Smell is an important criterion of the quality of atmospheric air. The paper looks at quantitative and qualitative methods of odor assessment and describes the method of field olfactometry. Studies were carried out on the spread of odor from the WWTP OAO OKOS in the Kaliningrad region of Russia which resulted in 817 measurements. For each measurement, the following parameters were recorded: odor strength (D/T), odor character, atmospheric pressure (mmHg), temperature (°C), relative humidity (%), wind speed (m/s), wind direction and the the point where a measurement was taken. A mathematical model is given of the dependence of odor strength on the distance to two sources s1 (m) and s2 (m) and the wind direction from a straight line passing through a given point and a source 1 — a1 or a source 2 — a2.

scholarly journals The complex moment problem: determinacy and extendibility

2019 ◽  
Vol 124 (2) ◽  
pp. 263-288 ◽  
Author(s):  
Dariusz Cichoń ◽  
Jan Stochel ◽  
Franciszek Hugon Szafraniec
Keyword(s):  
Partial Solution ◽  
Positive Definite ◽  
Lattice Points ◽  
Moment Sequence ◽  
Representing Measure ◽  
Straight Line Passing ◽  
Straight Line ◽  
Plane Algebraic Curve ◽  
Line Passing ◽  
Point Set

Complex moment sequences are exactly those which admit positive definite extensions on the integer lattice points of the upper diagonal half-plane. Here we prove that the aforesaid extension is unique provided the complex moment sequence is determinate and its only representing measure has no atom at $0$. The question of converting the relation is posed as an open problem. A partial solution to this problem is established when at least one of representing measures is supported in a plane algebraic curve whose intersection with every straight line passing through $0$ is at most one point set. Further study concerns representing measures whose supports are Zariski dense in $\mathbb{C} $ as well as complex moment sequences which are constant on a family of parallel “Diophantine lines”. All this is supported by a bunch of illustrative examples.

Loci of Points Equally Spaced From Two Given Geometrical Figures. Part 1

2017 ◽  
Vol 5 (3) ◽  
pp. 21-35 ◽  
Author(s):  
Владимир Вышнепольский ◽  
Vladimir Vyshnyepolskiy ◽  
Николай Сальков ◽  
Nikolay Sal'kov ◽  
Е. Заварихина ◽  
...  
Keyword(s):  
Cylindrical Surface ◽  
Parabolic Cylinder ◽  
Straight Line Passing ◽  
Sphere Center ◽  
Positive Gaussian Curvature ◽  
Straight Line ◽  
Paraboloid Of Revolution ◽  
Line Passing ◽  
The One ◽  
The Given

Loci of points (LOP) equally spaced from two given geometrical figures are considered. Has been proposed a method, giving the possibility to systematize the loci, and the key to their study. The following options have been considered. A locus equidistant from N point and l straight line. N belongs to l. We have a plane that is perpendicular to l and passing through N. N does not belong to l – parabolic cylinder. A locus equidistant from F point and a plane. In the general case, we have a paraboloid of revolution. The F point belongs to the given plane. We get a straight line perpendicular to the plane and passing through the F point. A locus equidistant from a point and a sphere. The point coincides with the sphere center. We get the sphere with a radius of 0.5 R. The point lies on the sphere. We get the straight line passing through the sphere center and the point. The point does not coincide with the sphere center, but is inside the sphere. We get the ellipsoid. The point is outside the sphere. We have parted hyperboloid of rotation. A locus equidistant from a point and a cylindrical surface. The point lies on the cylindrical surface’s axis. We get the surface of revolution which generatix is a parabola. The point lies on the generatrix of the cylindrical surface of rotation. We get a straight line, perpendicular to that generatrix and passing through the cylinder axis. The point does not lie on the axis, but is located inside the cylindrical surface. We get the surface with a horizontal sketch line – the ellipse, and a front sketch lines – two different parabolas. The point is outside the cylindrical surface. A locus consists of two surfaces. The one with the positive Gaussian curvature, and the other – with the negative one.

Basic slags and mineral phosphates

1925 ◽  
Vol 15 (1) ◽  
pp. 36-46
Author(s):  
Ernest Vanstone
Keyword(s):  
Constant Error ◽  
Soluble Phosphate ◽  
Constant Independent ◽  
Straight Line Passing ◽  
Total Phosphate ◽  
Small Constant ◽  
Straight Line ◽  
Line Passing ◽  
Straight Lines ◽  
The Relationship

(1) The relationship between phosphate soluble in 2 per cent, citric acid and total phosphate present has been investigated in the following cases:(a) Phosphates of known composition.(b) Basic Slags.(c) Mineral Phosphates.(2) The relationship is best shown graphically and in nearly all the above cases is a straight line passing through the origin.For each of three basic slags of widely differing citric solubility, the graphis a straight line showing that citric solubility is a definite constant, independent of the weight taken in the test, when allowance is made for a small constant error in the determination.(3) The ratio soluble phosphate/total phosphate in the case of the mineral phosphates Gafsa, Ephos, Nauru, and a West Indian phosphate, depends on the weight taken in the test, the graphs are not straight lines.

Weather and the Yield of a Crop

1975 ◽  
Vol 11 (3) ◽  
pp. 183-186 ◽  
Author(s):  
M. A. V. Devanathan
Keyword(s):  
Vegetative Growth ◽  
Strongly Correlated ◽  
Empirical Expression ◽  
Straight Line Passing ◽  
Weather Parameter ◽  
Straight Line ◽  
Sunshine Hours ◽  
Line Passing

SUMMARYThe growth of plants is controlled by the availability of photosynthesized carbohydrates. Since both rainfall and sunshine are needed for photosynthesis an empirical expression is proposed which relates vegetative growth to the product of rainfall and bright sunshine hours over a specified period. Tea is a crop in which the yield is entirely vegetative and harvested throughout the year. Laycock's data for tea yields from constant treatment plots in Malawi show that yield was strongly correlated with the product of rainfall per month (R) and average daily hours of sunshine per month (S) for the previous month (r=0·972). The graph of yield vs RS for the previous month gives a straight line passing through the origin. This empirical weather parameter RS appears suitable for the study of vegetative harvests.

Pulse radiolysis of deuterated aqueous LiCl glasses. Dependence of the yields and rates of reaction of visible and infrared absorbing trapped electrons on LiCl concentration

1978 ◽  
Vol 56 (14) ◽  
pp. 1889-1897 ◽  
Author(s):  
Hugh A. Gillis ◽  
George G. Teather ◽  
George V. Buxton
Keyword(s):  
Low Temperatures ◽  
Pulse Radiolysis ◽  
Hydration Number ◽  
Water Environment ◽  
Trapped Electrons ◽  
Straight Line Passing ◽  
Straight Line ◽  
Rate Of Reaction ◽  
Line Passing ◽  
The Difference

The yields and reactions of trapped electrons which absorb in the visible (evis−) and infrared (eir−) have been studied by pulse radiolysis in deuterated aqueous 6–15 M LiCl glasses at low temperatures. At 76 K G(evis−) increases and G(eir−) decreases as the concentration of LiCl is increased, but [Formula: see text] over the whole concentration range. Because the hydration number of Li+ is 4, G(eir−)/G(evis−) was plotted against [free D2O]/[LiCl•4D2O] and found to give a straight line passing through the origin, for [D2O]/[LiCl] > 4. From this proportionality it is concluded that eir− is an electron trapped in a purely amorphous water environment and evis− is mainly associated with water bound to Li+.The reactions of eir− and evis− with Cu(II) and SeO42− have been investigated. At 138 K the rate of reaction of evis− with SeO42− increases with decreasing [LiCl] whereas its rate of reaction with Cu(Il) is slower and independent of [LiCl]. At 76 K, where the rates of reaction of eir− with the scavengers can also be measured, it is found that in each case evis− and eir− react more slowly in 12 M LiCl glass than in 6 M LiCl glass, the difference being more marked for SeO42−. In the absence of scavenger the electron in the smaller yield decays faster. These observations can be rationalized on the basis that electrons can tunnel in either direction between visible and infrared traps before being scavenged, and it seems they cannot be rationalized in terms of direct tunnelling only.G(Cl2−) is found to be proportional to the electron fraction of Cl−•3D2O in the glass and its extrapolated value for pure Cl−•3D2O is 3.4. It is inferred that Cl2− arises mainly from ionization of the D2O bound to Cl−.

scholarly journals A Problem of Robert Simson's

1912 ◽  
Vol 31 ◽  
pp. 94-96
Author(s):  
G. Philip
Keyword(s):  
Fixed Point ◽  
Straight Line Passing ◽  
Constant Angle ◽  
Straight Line ◽  
Line Passing ◽  
Pass Through ◽  
Straight Lines

The following problem appears in Robert Simson's “Opera Quaedam Reliqua,” pp. 472–504 :“ Si a duobus punctis datis A, B ad circulum positione datum CDE inflectantur utcumque duae rectae AC, BC circumferentiae rursus in D, E occurrentes; juncta DE vel continebit datum angulum cum recta ad datum punctum vergente ; vel parallela erit rectae positionae datae; vel verget ad datum punctum:” i.e. if from two given points A and B any two straight lines AC, BC are drawn to a circle CDE given in position, and they meet the circumference again in D and E, then the straight line DE (I.) will inake a constant angle with a straight line passing through a fixed point, or (II.) will be parallel to a straight line given in position, or (III.) will pass through a given point. This final form of the result was only arrived at by Simson after he obtained the aid of Matthew Stewart.

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