Potash for Quality of Agricultural Commodities

2021 ◽  
pp. 49-59
Author(s):  
Abdul Wakeel ◽  
Muhammad Ishfaq
Keyword(s):  
Agricultural Commodities

The Import of Firearms into West Africa 1750–1807: a quantitative analysis

1977 ◽  
Vol 18 (3) ◽  
pp. 339-368 ◽  
Author(s):  
J. E. Inikori
Keyword(s):  
Eighteenth Century ◽  
Quantitative Analysis ◽  
West Africa ◽  
Crop Protection ◽  
Strong Preference ◽  
African History ◽  
Agricultural Commodities

A series of articles on firearms in Africa published in the Journal of African History in 1971 raised a number of questions which have not been given adequate attention since those articles appeared. In the present paper an attempt is therefore made to shed some light on some of these questions in relation to West Africa in the second half of the eighteenth century. On the basis of import figures from England total imports during this period was estimated to be between 283,000 and 394,000 guns per annum, excluding imports into the Congo–Loango area which Phyllis Martin estimated to be about 50,000 yearly at this time. These guns went largely to the major slave exporting regions of West Africa, especially the Bonny trading area. The sellers of slaves showed a very strong preference for firearms, which is an indication of a strong connexion between guns and the acquisition of slaves. This reinforces the gun-slave cycle thesis. The evidence fails to support the idea that firearms were used primarily for crop protection in West Africa in the eighteenth century. If this were so it should have been reflected in the European goods demanded by sellers of agricultural commodities. It is likely, however, that the use to which firearms were put in West Africa changed after 1900. While the quality of firearms imported into West Africa during the period of this study was generally low, it would seem that those firearms largely served the purposes for which the African buyers purchased them.

scholarly journals Mapa towarowości rolnictwa w Koncepcji Przestrzennego Zagospodarowania Kraju 2030 = Map of agricultural commodity in the National Spatial Development Concept 2030

2020 ◽  
Vol 57 ◽  
pp. 81-87
Author(s):  
Przemysław Śleszyński
Keyword(s):  
Rural Areas ◽  
Total Population ◽  
Agricultural Land ◽  
Spatial Development ◽  
Agricultural Commodities ◽  
Agricultural Commodity ◽  
Natural Conditions ◽  
Production Space ◽  
Development Concept

The article presents a map, which was compiled in 2009 in cooperation with Prof. Roman Kulikowski for the National Spatial Development Concept 2030. It concerns the inclusion of agricultural commodities in connection with natural conditions for the development of this sector of economy. For the typology, a division into the following classes was proposed: in terms of the quality of agricultural production space: A – up to 45 points, B – 45.1 to 60 points, C – above 60 points and in terms of commodity quality per 1 ha of agricultural land: 1 – up to 1,000 PLN, 2 – 1,000 up to 2,000 PLN, 3 – above 2,000 PLN. It has been shown that in Poland there is no stronger interdependence between natural conditions and agricultural commercialization. The resulting typology was further used to show changes within particular 9 distinguished types in terms of total population and post-productive age in agglomeration (suburban) and non-agglomeration areas. A disturbing phenomenon of relatively fast depopulation and ageing of the population in areas with good natural conditions for the development of agricultural function was detected. If this is not related to agrarian overpopulation, it is a serious obstacle to the desired transformations in Polish agriculture. Typology of communes, due to natural conditions and agricultural commodities may be useful for research on the processes taking place in rural areas presenting diverse development level.

scholarly journals Mushroom Cultivation as a Viable Income Generating Unit for Livelihood Security: A Success Story of ARYA Project at Turkaulia Block of East Champaran

2020 ◽  
pp. 78-81
Author(s):  
Arvind Kumar Singh ◽  
Neelam Kumari ◽  
Ram Babu Sharma ◽  
Shri Kant ◽  
Jitendra Rajput ◽  
...  
Keyword(s):  
Market Demand ◽  
Mushroom Cultivation ◽  
Agricultural Commodities ◽  
Success Story ◽  
Livelihood Security ◽  
Mushroom Production

To make agriculture sustainable, the price of agricultural commodities must be sufficient but variations in price may occur depending on market demand. So, by adopting mushroom production at rural level farmers may minimize the price gap by price of their mushrooms and ultimately people get good quality of mushroom and mushroom based products like pickle at rural level. This sets good example and also increases extra income from the agriculture at rural level by youth.

Immunoferritin localization of intracellular antigens in positively stained frozen sections

1978 ◽  
Vol 36 (2) ◽  
pp. 168-169
Author(s):  
K. T. Tokuyasu
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Thin Layers ◽  
The Other ◽  
Positive Staining ◽  
Frozen Sections ◽  
The Past ◽  
Ultrathin Frozen Sections ◽  
Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

Lithography below 100 nm

1983 ◽  
Vol 41 ◽  
pp. 96-99
Author(s):  
L. D. Jackel
Keyword(s):  
Spatial Distribution ◽  
Electron Beam ◽  
Electron Scattering ◽  
Electron Beam Lithography ◽  
Substrate Material ◽  
Local Electron ◽  
Electron Dose ◽  
Positive Resist ◽  
Exposure Process

Most production electron beam lithography systems can pattern minimum features a few tenths of a micron across. Linewidth in these systems is usually limited by the quality of the exposing beam and by electron scattering in the resist and substrate. By using a smaller spot along with exposure techniques that minimize scattering and its effects, laboratory e-beam lithography systems can now make features hundredths of a micron wide on standard substrate material. This talk will outline sane of these high- resolution e-beam lithography techniques.We first consider parameters of the exposure process that limit resolution in organic resists. For concreteness suppose that we have a “positive” resist in which exposing electrons break bonds in the resist molecules thus increasing the exposed resist's solubility in a developer. Ihe attainable resolution is obviously limited by the overall width of the exposing beam, but the spatial distribution of the beam intensity, the beam “profile” , also contributes to the resolution. Depending on the local electron dose, more or less resist bonds are broken resulting in slower or faster dissolution in the developer.

Convergent Beam Electron Diffraction

1978 ◽  
Vol 36 (3) ◽  
pp. 304-315
Author(s):  
G. Lehmpfuhl
Keyword(s):  
Electron Diffraction ◽  
Diffraction Pattern ◽  
Crystal Surface ◽  
Diffraction Spot ◽  
Crystal Thickness ◽  
Large Area ◽  
Electron Microscopic ◽  
Additional Information ◽  
Microscopic Investigations

Introduction In electron microscopic investigations of crystalline specimens the direct observation of the electron diffraction pattern gives additional information about the specimen. The quality of this information depends on the quality of the crystals or the crystal area contributing to the diffraction pattern. By selected area diffraction in a conventional electron microscope, specimen areas as small as 1 µ in diameter can be investigated. It is well known that crystal areas of that size which must be thin enough (in the order of 1000 Å) for electron microscopic investigations are normally somewhat distorted by bending, or they are not homogeneous. Furthermore, the crystal surface is not well defined over such a large area. These are facts which cause reduction of information in the diffraction pattern. The intensity of a diffraction spot, for example, depends on the crystal thickness. If the thickness is not uniform over the investigated area, one observes an averaged intensity, so that the intensity distribution in the diffraction pattern cannot be used for an analysis unless additional information is available.

Observability of Very Thick Specimen by Using Transmission Scanning Electron Microscope

1971 ◽  
Vol 29 ◽  
pp. 26-27
Author(s):  
K. Shibatomi ◽  
T. Yamanoto ◽  
H. Koike
Keyword(s):  
Electron Microscope ◽  
Image Quality ◽  
Scanning Electron Microscope ◽  
Chromatic Aberration ◽  
Image Contrast ◽  
Objective Lens ◽  
Thick Specimen ◽  
Transmission Electron ◽  
Scanning Electron

In the observation of a thick specimen by means of a transmission electron microscope, the intensity of electrons passing through the objective lens aperture is greatly reduced. So that the image is almost invisible. In addition to this fact, it have been reported that a chromatic aberration causes the deterioration of the image contrast rather than that of the resolution. The scanning electron microscope is, however, capable of electrically amplifying the signal of the decreasing intensity, and also free from a chromatic aberration so that the deterioration of the image contrast due to the aberration can be prevented. The electrical improvement of the image quality can be carried out by using the fascionating features of the SEM, that is, the amplification of a weak in-put signal forming the image and the descriminating action of the heigh level signal of the background. This paper reports some of the experimental results about the thickness dependence of the observability and quality of the image in the case of the transmission SEM.

The Current Situation in Chemical Stabilization of Biological Materials

1972 ◽  
Vol 30 ◽  
pp. 132-133
Author(s):  
John H. Luft
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Osmium Tetroxide ◽  
Molecular Level ◽  
Cross Linking ◽  
Chemical Stabilization ◽  
Specimen Preparation ◽  
Sufficient Condition ◽  
Radio Telescopes

With information processing devices such as radio telescopes, microscopes or hi-fi systems, the quality of the output often is limited by distortion or noise introduced at the input stage of the device. This analogy can be extended usefully to specimen preparation for the electron microscope; fixation, which initiates the processing sequence, is the single most important step and, unfortunately, is the least well understood. Although there is an abundance of fixation mixtures recommended in the light microscopy literature, osmium tetroxide and glutaraldehyde are favored for electron microscopy. These fixatives react vigorously with proteins at the molecular level. There is clear evidence for the cross-linking of proteins both by osmium tetroxide and glutaraldehyde and cross-linking may be a necessary if not sufficient condition to define fixatives as a class.

Resistance Monitor and Control for Vacuum Evaporation of Metals and Carbon

1976 ◽  
Vol 34 ◽  
pp. 572-573
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe ◽  
J. Michael Moseley
Keyword(s):  
Electronic Device ◽  
Point Sources ◽  
High Contrast ◽  
Variable Resistor ◽  
Quality Of Results ◽  
Low Contrast ◽  
Evaporation Source ◽  
And Control ◽  
At Will

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.

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