Structure et réactivité. III., Evolutions stéréochimiques et chemins réactionnels des radicaux cyclohexyles substitués en 2 et cyclohexényles substitués en 3 (réaction de Kochi)

1979 ◽  
Vol 57 (10) ◽  
pp. 1257-1261 ◽  
Author(s):  
Maurice Monnier ◽  
Jean-Pierre Aycard
Keyword(s):  
Carboxylic Acids ◽  
Steric Hindrance ◽  
High Energy ◽  
Radical Center ◽  
The Difference

The chlorodecarboxylation reaction (Kochi reaction) of a series of cyclohexane and cyclohexene carboxylic acids was investigated. Competitive acetoxy decarboxylation occurs, and the proportion of acetates is shown to increase with steric hindrance due to the R-substituent relative to the radical center. A partial evolution involving high energy conformers is suggested to explain the difference of stereoselectivities in the formation of acetates and chlorides.

Correlation Between the V-I Characteristics of (0001) 4H-SiC PN Junctions Having Different Structural Features and Synchrotron X-ray Topography

2008 ◽  
Vol 1069 ◽  
Author(s):  
Ryoji Kosugi ◽  
Toyokazu Sakata ◽  
Yuuki Sakuma ◽  
Tsutomu Yatsuo ◽  
Hirofumi Matsuhata ◽  
...  
Keyword(s):  
High Energy ◽  
Structural Features ◽  
Incidence Geometry ◽  
Voltage Source ◽  
Large Area ◽  
Chip Area ◽  
Power Mosfets ◽  
X Ray ◽  
Pn Junctions ◽  
The Difference

ABSTRACTIn practical use of the SiC power MOSFETs, further reduction of the channel resistance, high stability under harsh environments, and also, high product yield of large area devices are indispensable. Pn diodes with large chip area have been already reported with high fabrication yield, however, there is few reports in terms of the power MOSFETs. To clarify the difference between the simple pn diodes and power MOSFETs, we have fabricated four pn-type junction TEGs having the different structural features. Those pn junctions are close to the similar structure of DIMOS (Double-implanted MOS) step-by-step from the simple pn diodes. We have surveyed the V-I characteristics dependence on each structural features over the 2inch wafer. Before their fabrication, we formed grid patterns with numbering over the 2inch wafer, then performed the synchrotron x-ray topography observation. This enables the direct comparison the electrical and spectrographic characteristics of each pn junctions with the fingerprints of defects.Four structural features from TypeA to TypeD are as follows. TypeA is the most simple structure as same as the standard pn diodes formed by Al+ ion implantation (I/I), except that the Al+ I/I condition conforms to that of the p-well I/I in the DIMOS. The JTE structure was used for the edge termination on all junctions. While the TypeA consists of one p-type region, TypeB and TypeC consists of a lot of p-wells. The difference of Type B and C is a difference of the oxide between the adjacent p-wells. The oxide of TypeB consists of the thick field oxide, while that of TypeC consists of the thermal oxide corresponding to the gate oxide in the DIMOS. In the TypeD structure, n+ region corresponding to the source in the DIMOS was added by the P+ I/I. The TypeD is the same structure of the DIMOS, except that the gate and source contacts are shorted. The V-I measurements of the pn junctions are performed using the KEITHLEY 237 voltage source meters with semi-auto probe machine. An active area of the fabricated pn junctions TEGs are 150um2 and 1mm2. Concentration and thickness of the drift layer are 1e16cm−3 and 10um, respectively.In order to compare the V-I characteristics of fabricated pn junctions with their defects information that obtained from x-ray topography measurements directly, the grid patterns are formed before the fabrication. The grid patterns were formed over the 2inch wafer by the SiC etching. The synchrotron x-ray topography measurements are carried out at the Beam-Line 15C in Photon-Factory in High-Energy-Accelerator-Research-Organization. Three diffraction conditions, g=11-28, -1-128, and 1-108, are chosen in grazing-incidence geometry (improved Berg-Barrett method).In the presentation, the V-I characteristics mapping on the 2inch wafer for each pn junctions, and the comparison of V-I characteristics with x-ray topography will be reported.

scholarly journals Overheating In Silicon During Pulsed-Laser Irradiation?

1985 ◽  
Vol 51 ◽  
Author(s):  
B. C. Larson ◽  
J. Z. Tischler ◽  
D. M. Mills
Keyword(s):  
Laser Irradiation ◽  
Thermal Strain ◽  
Pulsed Laser ◽  
Interface Velocity ◽  
High Energy ◽  
Time Resolved ◽  
Synchrotron Source ◽  
Zero Velocity ◽  
The Difference ◽  
Pulsed Laser Irradiation

ABSTRACTNanosecond resolution time-resolved x-ray diffraction measurements of thermal strain have been used to measure the interface temperatures in silicon during pulsed-laser irradiation. The pulsed-time-structure of the Cornell High Energy Synchrotron Source (CHESS) was used to measure the temperature of the liquid-solid interface of <111> silicon during melting with an interface velocity of 11 m/s, at a time of near zero velocity, and at a regrowth velocity of 6 m/s. The results of these measurements indicate 110 K difference between the temperature of the interface during melting and regrowth, and the measurement at zero velocity shows that most of the difference is associated with undercooling during the regrowth phase.

scholarly journals Towards Sustainable Development: Building’s Retrofitting with PCMs to Enhance the Indoor Thermal Comfort in Tropical Climate, Malaysia

2021 ◽  
Vol 13 (7) ◽  
pp. 3614
Author(s):  
Zeyad Amin Al-Absi ◽  
Mohd Isa Mohd Hafizal ◽  
Mazran Ismail ◽  
Azhar Ghazali
Keyword(s):  
Climate Change ◽  
Sustainable Development ◽  
Thermal Comfort ◽  
Phase Change Materials ◽  
Thermal Environment ◽  
High Energy ◽  
Transition Temperatures ◽  
Indoor Thermal Environment ◽  
Adaptive Thermal Comfort ◽  
The Difference

Building sector is associated with high energy consumption and greenhouse gas emissions, which contribute to climate change. Sustainable development emphasizes any actions to reduce climate change and its effect. In Malaysia, half of the energy utilized in buildings goes towards building cooling. Thermal comfort studies and adaptive thermal comfort models reflect the high comfort temperatures for Malaysians in naturally conditioned buildings, which make it possible to tackle the difference between buildings’ indoor temperature and the required comfort temperature by using proper passive measures. This study investigates the effectiveness of building’s retrofitting with phase change materials (PCMs) as a passive cooling technology to improve the indoor thermal environment for more comfortable conditions. PCM sheets were numerically investigated below the internal finishing of the walls. The investigation involved an optimization study for the PCMs transition temperatures and quantities. The results showed significant improvement in the indoor thermal environment, especially when using lower transition temperatures and higher quantities of PCMs. Therefore, the monthly thermal discomfort time has decreased completely, while the thermal comfort time has increased to as high as 98%. The PCM was effective year-round and the optimum performance for the investigated conditions was achieved when using 18mm layer of PCM27-26.

scholarly journals The effect of soybean formula and formula 100 supplementation on the growth of preschool children

2016 ◽  
Vol 45 (6) ◽  
pp. 256
Author(s):  
M Mexitalia ◽  
Yohanes Tri Nugroho ◽  
J C Susanto
Keyword(s):  
Preschool Children ◽  
Body Height ◽  
High Energy ◽  
Second Phase ◽  
Z Score ◽  
Health Food ◽  
Alternative Health ◽  
Second Phases ◽  
The Difference ◽  
Weight For Age

Background Preschool children are vulnerable in growth. Soy-bean formula (SF) and formula-100 (F100) are supplementary foodswhich contain of high energy and are available at low price; how-ever, they are not widely used for preschool children.Objectives To investigate the effect of SF compared to F100 onthe growth of preschool children.Methods A cross-over trial was conducted on 96 preschool chil-dren aged 4-7 years. Subjects were randomly divided into 2 groupswhich received 200 ml soybean formula (n=49) or F100 (n=47) for1 month and crossed-over after a six-week wash-out period. Bodyweight was measured weekly. Body height and food analysis by 3-day food recall were measured at the beginning and the end of thestudy. The criteria of the acceptability of the formula was eithergood or poor.Results Supplementation with SF as well as F100 induced catchup growth as shown by the increase of Δz-score. There were nosignificant difference of Δ weight for age z-score, Δ height for agez-score, and Δ weight for height z score between groups duringthe first and second phases of the trial. The acceptability of F100was significantly better than that of SF at the beginning; neverthe-less, the difference was not significant at the second phase trial.Conclusions Soybean formula and F100 given for a one monthperiod can induce catch-up growth in preschool children. Soybeanformula as an alternative health food can be accepted by preschoolchildren

scholarly journals The Impact of China’s Low-Carbon Initiative on the Location Expansion of International SPA Enterprises

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Zhaoyang Zhao ◽  
Chong Ye
Keyword(s):  
Economic Development ◽  
Product Life Cycle ◽  
Large Scale ◽  
High Energy ◽  
Inhibitory Effect ◽  
Low Carbon ◽  
Suppression Effect ◽  
Carbon Neutrality ◽  
The Difference ◽  
The Impact

“Fast fashion” represents a short product life cycle, and international SPA enterprises are therefore criticised as representatives of high energy consumption, pollution, and emissions, which is contrary to China’s goal of achieving carbon neutrality. In the context of China’s shift to a low-carbon economic development model, how should SPA enterprises breakthrough in the face of China’s large-scale market advantage and domestic demand potential? Based on the statistics of 277 prefecture-level cities from 2010 to 2018, this article selects 5 leading international SPA enterprises and uses the difference-in-differences (DID) method to explore the impact of low-carbon initiative on the location expansion of international SPA enterprises. The results suggest that the quantity of location expansions of SPA enterprises in the pilot cities is significantly lower by approximately 0.418 units compared with the nonpilot cities, implying that the low-carbon initiative has a significant inhibitory effect on the location expansion of SPA enterprises. After a series of robustness tests, the conclusion is valid. The results of the heterogeneity test suggest that the suppression effect is mainly found in the subsample of central cities and cities with medium and low levels of economic development. This article proposes that SPA enterprises should reduce their carbon emissions and gradually explore a green and sustainable development path.

scholarly journals Accurate technologies of agricultural crops cultivation for organic farming

2021 ◽  
Vol 843 (1) ◽  
pp. 012028
Author(s):  
V F Kirdin ◽  
Yu A Laptina
Keyword(s):  
Spring Barley ◽  
Wheat Yield ◽  
Farming Systems ◽  
High Energy ◽  
High Productivity ◽  
Winter Triticale ◽  
The Difference ◽  
Leguminous Crops ◽  
Rotation Crop ◽  
Yield Of Oats

Abstract The article presents the results of many years of experiments on the development of energy-saving farming systems. Preference in crop rotations should be given to multi-depth combined treatments that provide high productivity and are characterized by high-energy efficiency. Data on the yield of grain and leguminous crops in a six-field grain crop rotation with constant dump and combined longline tillage shows that the yield of oats in the first year of rotation according to the experimental variants was the same and amounted to 3.60 t/ha. In the second year of winter wheat yield in the variant with longline tillage was by 0.20 t/ha more in comparison with a plow on row, in the third year the difference in yield of spring barley on options for primary processing amounted to 0.30 t/ha in favor of combined tiered processing, in the fourth year the yield of peas has also been found to 0.40 t/ha more, also on the option of combined longline processing in the fifth year of the rotation crop of winter triticale. The yield of oats was 0.30 t/ha higher, and in the sixth year the yield of oats was 0.40 t/ha higher on the variant of combined longline processing.

scholarly journals Understanding the Reasons behind the Energy Performance Gap of an Energy-Efficient Building, through a Probabilistic Approach and On-Site Measurements

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6178
Author(s):  
Pierryves Padey ◽  
Kyriaki Goulouti ◽  
Guy Wagner ◽  
Blaise Périsset ◽  
Sébastien Lasvaux
Keyword(s):  
Energy Efficient ◽  
Probabilistic Approach ◽  
Energy Performance ◽  
High Energy ◽  
Performance Gap ◽  
Post Evaluation ◽  
Energy Efficient Buildings ◽  
Ex Post ◽  
The Difference ◽  
Energy Efficient Building

The performance gap, defined as the difference between the measured and the calculated performance of energy-efficient buildings, has long been identified as a major issue in the building domain. The present study aims to better understand the performance gap in high-energy performance buildings in Switzerland, in an ex-post evaluation. For an energy-efficient building, the measured heating demand, collected through a four-year measurement campaign was compared to the calculated one and the results showed that the latter underestimates the real heating demand by a factor of two. As a way to reduce the performance gap, a probabilistic framework was proposed so that the different uncertainties of the model could be considered. By comparing the mean of the probabilistic heating demand to the measured one, it was shown that the performance gap was between 20–30% for the examined period. Through a sensitivity analysis, the active air flow and the shading factor were identified as the most influential parameters on the uncertainty of the heating demand, meaning that their wrong adjustment, in reality, or in the simulations, would increase the performance gap.

Solar neutron flux in the energy range 20–160 MeV

1970 ◽  
Vol 48 (18) ◽  
pp. 2155-2161 ◽  
Author(s):  
C. Y. Kim
Keyword(s):  
Neutron Flux ◽  
Energy Range ◽  
Sunspot Number ◽  
Solar Flares ◽  
Energy Region ◽  
High Energy ◽  
The Sun ◽  
Solar Neutron ◽  
Nuclear Emulsions ◽  
The Difference

An attempt to measure the flux of high-energy solar neutrons was made by measuring the difference in flux from the direction of the sun and from the symmetrical direction about the zenith, using oriented nuclear emulsions flown by balloon on July 30, 1966 from Fort Churchill, Manitoba.An excess of (2.2 ± 2.5) × 10−2 neutrons cm−2 s−1 was observed from the direction of the sun in the energy region of 20–160 MeV. On the day of the flight the sunspot number was 63, and no major solar flares were reported.

Thermal Performance Comparison between Single and Double Storey Terrace Houses in Melaka, Malaysia

2016 ◽  
Vol 835 ◽  
pp. 416-422
Author(s):  
Fahanim Abdul Rashid ◽  
Asrul Mahjuddin Ressang Aminuddin ◽  
Norafida Ab. Ghaffar
Keyword(s):  
Relative Humidity ◽  
Thermal Comfort ◽  
Case Studies ◽  
Thermal Performance ◽  
High Energy ◽  
Performance Comparison ◽  
Building Envelope ◽  
The Difference ◽  
Economic Developments ◽  
Housing Typology

Over the past decade many studies were conducted to investigate the thermal performance of terraced houses in Malaysia. It was found that this housing typology failed to address the need for thermal comfort and alternatives to the narrow frontage with deep plan have been proposed with simulated good thermal performance. Although this is good progress for new generation of terraced houses, millions of units of terraced houses are still in use and new units with the outdated existing plans continued to get built due to consistently very high demand due to progressive urbanisation and rapid economic developments. Therefore, it is imperative that the thermal comfort issue for existing terraced houses is dealt with and through this paper a comparison between single and double storey terraced houses is made through analysis of indoor environmental monitoring (ambient temperature, relative humidity and air velocity) of two (2) selected case studies in Merlimau, Melaka. Contrary to popular belief, it is found that there is no statistical difference between both sets of indoor temperature and relative humidity between the case studies. This finding is indicative of the consistent and stable temporal temperature highs and lows in a 24 hour cycle despite the difference in indoor volume and distance between the ground floor and the roof cavity. Much of the reason is due to the materiality of the terraced houses construction and unsealed and uninsulated building envelope. Therefore, further research into improving the thermal performance of existing terraced houses of any typology have to be conducted to allow thermal comfort and to reduce reliance on high energy consuming air-conditioning.

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