ON THE HYDROGENATION OF BITUMEN FROM THE BITUMINOUS SANDS OF ALBERTA II

1931 ◽  
Vol 4 (5) ◽  
pp. 517-539 ◽  
Author(s):  
E. H. Boomer ◽  
A. W. Saddington
Keyword(s):  
Adverse Effect ◽  
Temperature Control ◽  
Low Temperatures ◽  
Coke Formation ◽  
Absolute Rate ◽  
Rate Of Reaction ◽  
Series Of Experiments ◽  
Distillation Residues ◽  
Time Required ◽  
Repeated Runs

A second series of experiments on the batch hydrogenation of McMurray bitumen has been carried out. A cylindrical autoclave, of 1.8 litres capacity and designed for close temperature control and efficient agitation, is described.Hydrogenation of the larger part of the bitumen proceeded with ease and commenced at comparatively low temperatures. The rate of hydrogenation was dependent on temperature, presence of a catalyst and extent of hydrogenation. The reaction commenced slowly at 200 °C. and increased with rising temperature. The presence of molybdic anhydride approximately doubled the rate of reaction. The extent and rate of hydrogenation decreased on repeated runs with the same lot of bitumen due to the adverse effect of an increasing proportion of simple hydrocarbons.An increase in the relative amount of hydrogen to bitumen increased the absolute rate of reaction and degree of hydrogenation possible in one treatment. As a result of the shorter time required, coke formation was largely suppressed.Experiments on distillation residues from hydrogenated bitumen reveal the presence in bitumen of some 15% of asphaltic material which is very resistant to hydrogenation or cracking at temperatures as high as 500 °C. This material has not yet been hydrogenated without considerable coke formation but the problem does not appear to be insoluble.It appears that 75% of Alberta bitumen may be converted easily to gasoline and oil.

The Reactions of Substituted Germyl- and Silylhydrazines with BX3 and CY2 Acceptor Species

1972 ◽  
Vol 50 (4) ◽  
pp. 562-566 ◽  
Author(s):  
L. K. Peterson ◽  
K. I. Thé
Keyword(s):  
Molecular Weight ◽  
Nitrogen Atom ◽  
Low Temperatures ◽  
Adduct Formation ◽  
Steric Effects ◽  
Reaction Products ◽  
Hydrazine Derivatives ◽  
Basic Catalysts ◽  
Series Of Experiments ◽  
Electronic And Steric Effects

Boron trimethyl reacts with each of the organometalloid-hydrazine derivatives Me2NN(R)GeMe3 (R = H, Me, SiMe3) except Me2NN(SiMe3)GeMe3, and with Me2NNHSiMe3, forming 1:1 adducts. With Me2NN(SiMe3)GeMe3 and BMe3, no adduct was formed even at low temperatures. On the basis of p.m.r. spectra, the metalloid-substituted nitrogen atom rather than the terminal nitrogen, is indicated as the basic center at which adduct formation occurs. With BF3, the Si—N and Ge—N bonds of the hydrazine derivatives were cleaved, again indicating attack at the central nitrogen atom. In a series of experiments involving CY2 (Y = O, S) and Me2NN(R)MMe3 (R = H, Me, SiMe3; M = Si, Ge), reaction occurred readily for R = H, but less readily for R = Me and for the compound Me2NN(GeMe3)2, while no reaction was observed for the compounds Me2NN(SiMe3)2 and Me2NN(SiMe3)GeMe3, even when heat or basic catalysts were employed. Reaction products, carbamate and thiocarbamate derivatives, Me2NN(R)C(Y)YMMe3, were characterized on the basis molecular weight, i.r., p.m.r., and mass spectroscopy, and m.p. data. Ease of formation is discussed in terms of electronic and steric effects.

The Reactions of Organometallic Compounds Involving Silicon. Reactions of Triphenyl-, Diphenylmethyl-, and Phenyldimethylsilyl-lithium with 9-Phenylfluorene in Tetrahydrofuran

1972 ◽  
Vol 50 (23) ◽  
pp. 3761-3766 ◽  
Author(s):  
M. A. Hamid
Keyword(s):  
Low Temperatures ◽  
Initial Rate ◽  
Organometallic Compounds ◽  
Initial Reactant ◽  
Thermodynamic Constants ◽  
Rate Of Reaction ◽  
Stop Flow

Triphenyl-, diphenylmethyl-, and phenyldimethylsilyl-lithium react very rapidly with 9-phenylfluorene in tetrahydrofuran (THF) but the reaction can be followed spectroscopically using the stop-flow technique at low temperatures. The order of reaction, found from the dependence of the initial rate of reaction on the initial reactant concentrations, is unity in both 9-phenylfluorene and the relevant organosilyl-lithium reagent. The thermodynamic constants of activation for the reaction between 9-phenylfluorene and triphenylsilyl-lithium (Ph3SiLi), diphenylmethylsilyl-lithium (Ph2MeSiLi), and phenyldimethylsilyl-lithium (PhMe2SiLi), respectively, are: ΔH≠ = 4.5, 4.0, and 4.0 kcal mol−1; ΔG≠ = 13.0, 12.5, and 12.5 kcal mol−1; ΔS≠ = −34.9, −34.8, and −34.9 cal mol−1 deg−1

Toxic effects of ouabain on Purkinje fibers and ventricular muscle fibers

1962 ◽  
Vol 203 (3) ◽  
pp. 433-439 ◽  
Author(s):  
Mario Vassalle ◽  
Johannes Karis ◽  
Brian F. Hoffman
Keyword(s):  
Muscle Fibers ◽  
Toxic Effects ◽  
Resting Potential ◽  
Ventricular Muscle ◽  
Purkinje Fibers ◽  
Diastolic Depolarization ◽  
Series Of Experiments ◽  
Time Required ◽  
Induced Changes

Toxic effects of ouabain on single Purkinje fibers and ventricular muscle fibers were investigated in vitro by microelectrode technique. Toxicity developed much earlier in the specialized conducting fibers and consisted of a progressively increasing rate of diastolic depolarization and a decrease of amplitude and duration of the action potential. The majority of Purkinje fiber preparations developed extrasystoles and rapid spontaneous rhythms. The resting potential was much decreased. The ouabain-induced changes in ventricular muscle fibers occurred much later than did changes in Purkinje fibers and consisted of a decrease in the plateau and in the amplitude of the action and resting potential. Spontaneous depolarization was not observed in muscle fibers. The effect of the rate of stimulation on the development of ouabain toxicity was studied in another series of experiments on driven and quiescent muscles. Signs of toxicity appeared earlier in the driven muscles than in duplicate quiescent muscles and, at faster rates of stimulation, the time required for the toxic changes was shortened.

scholarly journals On a formula for the elastic force of vapour at different temperatures

1851 ◽  
Vol 5 ◽  
pp. 738-740
Keyword(s):  
High Temperatures ◽  
Low Temperatures ◽  
Elastic Force ◽  
French Academy ◽  
Different Temperatures ◽  
Series Of Experiments ◽  
Better Than

The author adopts as the basis of his formula the first series of experiments at high temperatures made by the French Academy, and those of Magnus at low temperatures. For the Academy’s experiments, he adopts the indications of the smaller thermometer in the steam in preference to those of the larger thermometer in the water. Of Dr. Young’s sort of formulae, he notices that of the Aca­demy and several others with exponents varying from 5 to 7. From the elasticity at freezing, as given by Magnus, compared with four of the Academy’s experiments, he shows that for the range of observation the number 6 is preferable to 5 as an exponent; but, as he states, no formula of this sort with a constant index can be found to agree with the observations throughout. The formula of Magnus he finds to agree with these observations better than any of the others; but being adapted to the air-thermo­meter, and therefore not convenient for ordinary use, he gives his own formula adapted to the mercurial thermometer, t = 500 + 225 log A / 5 - log A, t being the temp. Cent., and A the elasticity in atmospheres of 0 m .76 at zero, or 30 inches at 58° Fahr.; the temperature being given, the formula becomes log A = 5 - 1625 / 225 + t .

scholarly journals Production of Didymella rabiei Pseudothecia and Dispersal of Ascospores in a Mediterranean Climate

2005 ◽  
Vol 95 (11) ◽  
pp. 1279-1286 ◽  
Author(s):  
E. Gamliel-Atinsky ◽  
D. Shtienberg ◽  
H. Vintal ◽  
Y. Nitzni ◽  
A. Dinoor
Keyword(s):  
Low Temperature ◽  
Environmental Conditions ◽  
Low Temperatures ◽  
Mediterranean Climate ◽  
Temperature Requirement ◽  
Trap Plants ◽  
Series Of Experiments ◽  
The Mediterranean ◽  
Stem Segments

Temperature and wetness conditions required for development and maturation of Didymella rabiei pseudothecia were determined in a series of experiments conducted in controlled-environmental conditions. Initial stages of pseudothecium formation occurred at temperatures ranging from 5 to 15°C. Incubation at low temperatures was essential for subsequent pseudothecium maturation. This requirement was satisfied for chickpea stem segments incubated at 5 or 10°C for three consecutive weeks or during periods of 3 or 5 days, separated by periods at higher temperatures. Following the low-temperature requirement, subsequent pseudothecium development was independent of temperature in the range tested (5 to 20°C). Wetness was essential for pseudothecium production: pseudothecia formed and matured on stem segments maintained continuously wet but also on those exposed to periods of three or five wet days, separated by dry periods. The dispersal of D. rabiei ascospores was studied using chickpea plants as living traps in the field. Trap plants were infected mainly when exposed during rain but also in rainless periods. Results of this study enabled us to describe the developmental events leading to the production of the teleomorph stage and the dispersal of ascospores by D. rabiei in the Mediterranean climate of Israel.

Equipment for Preparing Electropolished TEM Specimens at Controlled and Low Temperatures

1987 ◽  
Vol 115 ◽  
Author(s):  
Vjekoslav Franetovic
Keyword(s):  
Stainless Steel ◽  
Temperature Control ◽  
Low Temperatures ◽  
Control Unit ◽  
Cooling Device ◽  
Dry Ice ◽  
Temperature Control Unit ◽  
Copper Coil ◽  
Heat Buildup

ABSTRACTA cooling device for use with the Fishione twin-jet electropolisher Model 110 has been developed for electropolishing TEM specimens at controlled and low temperatures necessary for some materials. This consists of an explosion-proof pump circulating methanol through a specially designed stainless steel bath, and a copper coil immersed in a mixture of methanol and dry ice in a dewar. A thermocouple with a temperature control unit provides precise temperature control.With this device, electropolishing can be conducted at temperatures as low as −55°C. This allows electropolishing of certain materials which cannot be polished with conventional equipment. The precisely controlled temperature also improves the performance of the electropolishing equipment at all temperatures because the success of electropolishing depends on maintaining constant conditions during the process. The unit further allows the use of aggressive electrolytes and preparation of solutions which could otherwise become hazardous due to heat buildup during electropolishing or preparation.

scholarly journals Photopreiodic and Temperature Control of Flower Initiation in the Late Pea Cultivar Greenfeast

1968 ◽  
Vol 21 (4) ◽  
pp. 609 ◽  
Author(s):  
DM Paton
Keyword(s):  
Temperature Control ◽  
Low Temperatures ◽  
Continuous Light ◽  
Flower Initiation ◽  
Temperature Responses

The number of green foliage leaves at initiation is related to a quantitative leaf requirement for flowering in the late pea cultivar Greenfeast. When grown in various temperature and photoperiod regimes the leaf requirement is least in continuous light and low temperatures. The additive nature of the photoperiodic and temperature responses suggests that photoperiod and temperature probably act independently.

scholarly journals Pengkondisian Udara Secara Otomatis Pada Proses Pasteurisasi Kumbung Jamur Merang Menggunakan ATMEGA8535

2016 ◽  
Vol 2 (1) ◽  
Author(s):  
Wardika Wardika ◽  
Karsid Karsid
Keyword(s):  
Control System ◽  
Lower Limit ◽  
Temperature Control ◽  
Air Conditioning ◽  
Temperature Control System ◽  
Air Conditioning System ◽  
Time Required

In this research designed an air conditioning system that is capable of reaching temperatures needed in the pasteurization process in miniature kumbung. The temperature required is approximately 70-80oC. The temperature was maintained for 4 hours. To maintain at that temperature control system designed 'on-off' by using a microcontroller ATMega 8535. This system works by shutting down the system when the temperature has been reached and revive the system when the temperature has dropped to the lower limit temperature setpoint. The results of this research in terms of the time required for the pasteurization process kumbung automatic mushroom faster at less than 5 hours compared kumbung regular mushrooms is 7-8 hours.

scholarly journals Novel Cross-View Human Action Model Recognition Based on the Powerful View-Invariant Features Technique

2018 ◽  
Vol 10 (9) ◽  
pp. 89 ◽  
Author(s):  
Sebastien Mambou ◽  
Ondrej Krejcar ◽  
Kamil Kuca ◽  
Ali Selamat
Keyword(s):  
Human Action Recognition ◽  
Human Action ◽  
Action Identification ◽  
Memory Space ◽  
Deep Model ◽  
Action Model ◽  
Series Of Experiments ◽  
Time Required ◽  
Model Recognition ◽  
Fine Tune

One of the most important research topics nowadays is human action recognition, which is of significant interest to the computer vision and machine learning communities. Some of the factors that hamper it include changes in postures and shapes and the memory space and time required to gather, store, label, and process the pictures. During our research, we noted a considerable complexity to recognize human actions from different viewpoints, and this can be explained by the position and orientation of the viewer related to the position of the subject. We attempted to address this issue in this paper by learning different special view-invariant facets that are robust to view variations. Moreover, we focused on providing a solution to this challenge by exploring view-specific as well as view-shared facets utilizing a novel deep model called the sample-affinity matrix (SAM). These models can accurately determine the similarities among samples of videos in diverse angles of the camera and enable us to precisely fine-tune transfer between various views and learn more detailed shared facets found in cross-view action identification. Additionally, we proposed a novel view-invariant facets algorithm that enabled us to better comprehend the internal processes of our project. Using a series of experiments applied on INRIA Xmas Motion Acquisition Sequences (IXMAS) and the Northwestern–UCLA Multi-view Action 3D (NUMA) datasets, we were able to show that our technique performs much better than state-of-the-art techniques.

scholarly journals EFEITO DE TELAS DE SOMBREAMENTO NO CRESCIMENTO E PROTEÇÃO DE MUDAS DE Toona ciliata SOB BAIXAS TEMPERATURAS

FLORESTA ◽  
2014 ◽  
Vol 44 (4) ◽  
pp. 607
Author(s):  
Rudinei De Marco ◽  
Bruno Conte ◽  
Edison Rogério Perrando ◽  
Fabiano De Oliveira Fortes ◽  
Lucindo Somavilla ◽  
...  
Keyword(s):  
Adverse Effect ◽  
Low Temperatures ◽  
Quality Index ◽  
Aerial Part ◽  
Single Layer ◽  
Dry Mass ◽  
Plastic Bags ◽  
Toona Ciliata ◽  
Santa Maria ◽  
Dickson Quality Index

O objetivo deste trabalho foi avaliar a influência de diferentes camadas de telas de sombreamento no crescimento e na proteção de mudas de Toona ciliata em períodos de suscetibilidade a geadas. O estudo foi conduzido na Universidade Federal de Santa Maria, Campus Frederico Westphalen, RS. Para a realização do experimento, mudas de Toona ciliata foram mantidas em sacos plásticos com capacidade de três litros e submetidas a quatro tratamentos: mudas sem proteção e mudas sob proteção com camada simples, dupla e tripla de sombreamento. O delineamento foi o inteiramente casualizado, com quatro repetições de oito mudas por repetição. Foi avaliado o número de mudas com folhas apicais necrosadas, a altura da parte aérea, o diâmetro do colo e a massa seca radicular, aérea e total. Por meio dessas variáveis, foi possível determinar o Índice de Produtividade, o Índice de Qualidade de Dickson e as relações altura/diâmetro e altura/massa seca da parte aérea. A utilização de telas de sombreamento mostrou-se eficiente para a proteção das mudas contra o efeito adverso da geada. O uso de uma camada simples de sombreamento resultou em maior proteção e consequentemente forneceu as melhores características dendrométricas em relação às demais intensidades de sombreamento.Palavras-chave: Tela de proteção; tolerância à geada; cedro australiano. AbstractEffect of shading screens on growth and protection of Toona ciliata seedlings under low temperatures. This research aimed to evaluate the influence of different shading screens layers on the growth and protection of Toona ciliata seedlings in periods of frost susceptibility. The research was conducted on the Santa Maria Federal University, Frederico Westphalen Campus, RS. For the experiment, Toona ciliata seedlings maintained in plastic bags with three liters of capacity each were submitted to four treatments: unprotected seedlings, seedlings under protection with a single shading layer, double and triple. The experimental design was the completely randomized, with four repetitions of eight seedlings each. It was evaluated the number of seedlings with necrosed apical leaves, the aerial part height, the lap diameter and the dry mass of root, aerial and total. By such variables, it was possible to determine the Produtivity Index, the Dickson Quality Index and the relations height/diameter and height/dry mass of aerial part. The use of shading screens showed up efficient to protect the seedlings against the adverse effect of frost. The use of a single layer of shading resulted in a greater protection and consequently provided the best dendrometric characteristics, compared to the others levels of shading.Keywords: Screen protection; tolerance to frost; Australian cedar.

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