Analysis of improving the edge quality and growth rate of single-crystal diamond growth using a substrate holder

CrystEngComm ◽  
2019 ◽  
Vol 21 (43) ◽  
pp. 6574-6584 ◽  
Author(s):  
Bo Yang ◽  
Qiao Shen ◽  
Zhiyin Gan ◽  
Sheng Liu
Keyword(s):  
Growth Rate ◽  
Single Crystal ◽  
Diamond Growth ◽  
Substrate Holder ◽  
Average Growth Rate ◽  
Average Growth ◽  
Single Crystal Diamond ◽  
Edge Quality

To improve the edge regions. Growth using the old substrate holder, the edge quality was improved, but the average growth rate decreased. So, a newly substrate holder was designed. The edge quality and the growth rate were both improved.

Towards Large Area Diamond Substrates: The Mosaic Process

1995 ◽  
Vol 416 ◽  
Author(s):  
Ger Janssen ◽  
John J. Schermer ◽  
L. J. Giling
Keyword(s):  
Growth Rate ◽  
Single Crystal ◽  
Diamond Growth ◽  
Large Area ◽  
Severe Problem ◽  
Step Process ◽  
Seed Crystals ◽  
Combustion Flame ◽  
Single Crystal Diamond ◽  
Hot Filament

ABSTRACTA method has been developed for producing large area single-crystal diamond plates, suitable for optical and electronic applications. It starts with orienting and closely packing a set of diamond seed crystals with (001) top faces. This assembly, or mosaic, is then joined by a single-crystal overgrowth using a CVD process. A number of assembling techniques have been tested for compatibility with homoepitaxial diamond growth by hot filament assisted CVD and/or growth and etching by the acetylene-oxygen combustion flame. Furthermore a two-step process is described. First an initial layer (20-50/μm) is deposited by hot filament assisted CVD at a low growth rate in order to bridge the gap between the seeds. Subsequently the fast growth rate of the acetylene-oxygen combustion flame is employed to increase the layer thickness (>250,μm). It was found that both the basic mosaic process as well as the two step process can produce a single-crystal diamond layer on top of mosaics consisting of seed crystals with well aligned crystallographic directions. The width of the gaps between the seed crystals (up to 25 μm) was found to be less critical, while the orientation of the side faces and the direction of the misorientation (i.e. the step flow direction) seem not to effect the successful overgrowth. Apart from the alignment of the seed crystals the most severe problem, which has to be overcome in order to obtain one single-crystal overgrowth, is the occurrence of penetration twins in the joint regions. The largest mosaic structure -up to now- overgrown by CVD consists of seven seed crystals and has a surface area slightly in excess of 1 cm2

scholarly journals PERFORMANCE EVOLUTION OF JAMMU AND KASHMIR STATE FINANCIAL CORPORATION

2021 ◽  
Vol 9 (08) ◽  
pp. 647-650
Author(s):  
Maryama Gul ◽  
◽  
P.K. Sanse ◽  
Keyword(s):  
Growth Rate ◽  
Trend Analysis ◽  
Ratio Analysis ◽  
Average Growth Rate ◽  
Jammu And Kashmir ◽  
Average Growth ◽  
Research Period ◽  
Study Performance

The objective of this study was to assess the performance of JK SFC. The establishment of State financial Corporations was, one of the steps taken, at the official level to promote the growth of small and mediumscale industries. The Jammu and Kashmir State Financial Corporation is a statutory Corporation established under SFCs Act 1951(Central Act 63 of 1951) which is facing heavy losses due to no source of funds and no recovery of loans. In the present study performance of JKSFC was analyzed with different tools like trend analysis and ratio analysis and average growth rate. The results of the study show that performance of JKSFC is declining during the research period due tofacing problems of liquidity & solvency.

scholarly journals Surface Morphology and Microstructure Evolution of Single Crystal Diamond during Different Homoepitaxial Growth Stages

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 5964
Author(s):  
Guoqing Shao ◽  
Juan Wang ◽  
Shumiao Zhang ◽  
Yanfeng Wang ◽  
Wei Wang ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Single Crystal ◽  
Cross Section ◽  
Growth Model ◽  
Diamond Growth ◽  
Step Flow ◽  
Homoepitaxial Growth ◽  
Diamond Substrate ◽  
Single Crystal Diamond ◽  
Step Flow Growth

Homoepitaxial growth of step-flow single crystal diamond was performed by microwave plasma chemical vapor deposition system on high-pressure high-temperature diamond substrate. A coarse surface morphology with isolated particles was firstly deposited on diamond substrate as an interlayer under hillock growth model. Then, the growth model was changed to step-flow growth model for growing step-flow single crystal diamond layer on this hillock interlayer. Furthermore, the surface morphology evolution, cross-section and surface microstructure, and crystal quality of grown diamond were evaluated by scanning electron microscopy, high-resolution transmission electron microcopy, and Raman and photoluminescence spectroscopy. It was found that the surface morphology varied with deposition time under step-flow growth parameters. The cross-section topography exhibited obvious inhomogeneity in crystal structure. Additionally, the diamond growth mechanism from the microscopic point of view was revealed to illustrate the morphological and structural evolution.

scholarly journals Cambodia: Subprime Degrees?

2013 ◽  
pp. 15-16 ◽  
Author(s):  
David Ford
Keyword(s):  
Higher Education ◽  
Growth Rate ◽  
Private Institutions ◽  
Average Growth Rate ◽  
Average Growth ◽  
Branch Campuses ◽  
The Past ◽  
New Institutions

The Cambodian economy has achieved a healthy average growth rate of about 7 percent, over the past decade. Higher education has expanded more than tenfold, in the same period, and now includes 91 institutions (68 universities and 23 institutes or schools) of which 59 percent are private institutions, and almost 200,000 students. Access has improved greatly, as many new institutions and branch campuses of existing institutions have opened in provincial centers.

Growth and carcass characteristics of crossbred lambs in various production systems

2012 ◽  
Vol 52 (5) ◽  
pp. 373 ◽  
Author(s):  
N. M. Fogarty ◽  
J. G. Mulholland
Keyword(s):  
Growth Rate ◽  
Production Systems ◽  
Growth Traits ◽  
Carcass Weight ◽  
Wagga Wagga ◽  
Hybrid Vigour ◽  
Average Growth Rate ◽  
Lower Growth ◽  
Average Growth ◽  
Lamb Growth

Lamb growth, carcass and pelt measurements are reported from 5775 lambs born to Border Leicester × Merino (BLM) and Hyfer (Dorset × Merino composite) ewes joined to Dorset, Suffolk and Hyfer rams in three lamb-production systems at Cowra and Wagga Wagga over 5 years. The production systems involved lambings at different seasons of the year and increasing levels of intensification from autumn annual joining, spring joining with a backup mating for non-pregnant ewes, to an accelerated 8-monthly lambing system. Lambs from BLM ewes were 0.7 kg heavier at birth and grew 3% faster and reached slaughter, at 18 kg carcass weight, 1–2 weeks earlier than did lambs from Hyfer ewes (P < 0.01). The advantage in growth rate of lambs from BLM compared with Hyfer ewes was greater for lambs born in November. These lambs had poorer growing conditions over the summer months, with 22% lower growth rate and taking 5 weeks longer to reach slaughter than did lambs born in March or August. There was no difference between Dorset and Suffolk sire breeds for any lamb growth traits, with lambs from Hyfer sires growing 7% slower. Ram and cryptorchid lambs reached slaughter 1 week earlier than did wethers, with ewes a further 9 days later (P < 0.01). Sex differences were maximised when lamb growth was greatest. There were no differences in carcass fat measurements between ram and cryptorchid lambs, although both were considerably leaner than wethers (2.2–3.0 mm fat at the GR site), which were 1.3–2.1 mm leaner than ewes at 18-kg carcass weight. The range in average growth rate of progeny of the BLM ewes from the 12 different source flocks at Cowra and Wagga Wagga was 10–14% of the mean which was twice the difference in average growth rate of progeny from the BLM and Hyfer dams. There was also significant variation among the BLM source flocks for carcass fat measurements. Lamb progeny from the different sire- and dam-breed combinations had varying levels of heterozygosity. There appears to be little loss of heterosis or hybrid vigour for lamb growth, although the sire breed × dam breed interaction was significant (P < 0.01) for age at slaughter at Wagga Wagga, in which the ranking of the lamb types was consistent with the levels of heterozygosity. The estimates of between-lambing repeatability for the ewes were highest for birthweight (0.35 Cowra and 0.27 Wagga Wagga) and declined at later ages (0.26–0.17), with lower estimates for carcass traits.

Performance of young breeding cattle in commercial herds in the south-west of Western Australia. 3. Calf growth, dystocia, and their relationship with production and fertility measurements in first-calf heifers

1991 ◽  
Vol 31 (4) ◽  
pp. 455 ◽  
Author(s):  
GJ Sawyer ◽  
DJ Barker ◽  
RJ Morris
Keyword(s):  
Growth Rate ◽  
Birth Weight ◽  
Western Australia ◽  
The South ◽  
Average Growth Rate ◽  
Average Growth ◽  
Calf Growth ◽  
South West ◽  
Condition Score ◽  
Recorded Data

The preweaning growth of the progeny from 2531 first-calf heifers calving on commercial properties in the south-west of Western Australia was studied over 5 years. Animals included the progeny of Angus sires mated to Angus, Angus x Friesian, Simford, Hereford and Beef Shorthorn crossbred heifers; the progeny of Hereford sires mated to Hereford, Hereford x Friesian, and Beef Shorthorn crossbred; and those of Devon crossbred, Simford or Wokalup multibreed heifers mated inter se. Calves were born between mid January and July of each year and date of birth, calving information and calf growth through to weaning at an average age of 230 days were recorded. Data recorded on the calves' dams included regular liveweight and condition score assessment and the date of second calving. Angus-sired calves were lighter at birth than Hereford-sired calves; breed means ranged from 25.1 kg for purebred Angus to 33.2 kg for Wokalup multibreeds, with male calves weighing 1.4 kg more than females at birth. Calf birth weight was positively and linearly related to weight of dam at the beginning of joining. Breed of calf, sex of calf, year of birth, day of the year born, liveweight and liveweight change of the dam at the beginning of rejoining all significantly influenced calf growth, with up to 64% of variation accounted for. At 50 days of age, Devon crossbreds, Simfords and Wokalup multibreeds were significantly heavier than crossbred Hereford or Angus calves, and this trend persisted until weaning. The average growth rate to 200 days of Angus calves was 0.113 kg/day slower, and Hereford calves 0.77 kg/day slower, than the average growth rate of their respective crossbred calves. Heaviest 200-day weights were found in Devon crossbred (235 kg), Simford (221 kg) and Wokalup multibreed (219 kg) calves. A strong seasonal influence on calf growth was detected. Each 1 day increase in calf age in calves born between mid January and June resulted in 0.29 kg extra liveweight at 100 days and 0.68 kg extra liveweight at 200 days of age. Overall, the liveweight of the dam at the beginning of re-joining was positively associated with calf growth, with 0.119 kg of calf liveweight/kg dam liveweight at 100 days and 0.123 kg at 200 days. There was less effect of dam liveweight in Herefords and Hereford x Friesians on calf growth to 200 days, but this relationship was closer in faster growing and later maturing breeds, including Angus x Friesian, Simford, and Wokalup multibreed. The dairy crossbreeds generally lost weight at the beginning of re-joining, resulting in a negative association between this weight change and calf growth to 100 days. No assistance was required in 93% of calvings and the highest incidence of dystocia corresponded with the highest birth weight calves in Wokalup multibreeds. The most common calving difficulty was an apparently slow birth where no assistance was given, resulting in a stillborn calf. Male calves experienced 3 times the level of dystocia recorded for female calves. There was no association detected between dystocia and dam liveweight subsequent to calving. The study highlighted the importance of dam breed, liveweight and condition of the dam and timing of calving as important influences on the growth of progeny reared by first-calf heifers.

scholarly journals Effects of salinity changes on growth performance and survival of climbing perch, Anabas testudineus (Bloch, 1795)

2016 ◽  
Vol 25 (1) ◽  
pp. 65-73
Author(s):  
Faijun Nahar ◽  
Wahida Haque ◽  
Dewan Ali Ahsan ◽  
Md Ghulam Mustafa
Keyword(s):  
Growth Rate ◽  
Growth Performance ◽  
Specific Growth ◽  
Control Group ◽  
Feed Conversion ◽  
Average Growth Rate ◽  
Anabas Testudineus ◽  
Average Growth ◽  
Climbing Perch ◽  
Cultured Fish

An experiment was carried out to find the salinity tolerance capability and growth performance of Climbing Perch, Anabas testudineus (Bloch, 1795). Anabas testudineus commonly cultured fish in Bangladesh was reared in laboratory conditions at different salinities of 0, 3, 6, 9, 12, 15, 18 and 21‰ for 60 days. Hundred per cent survivals were detected at 0, 3, 6 and 9‰ salinity while 100% mortality was recorded at 18 and 21‰ salinity. Various responses to threat and feeding were observed among the fish in different treatments. Lowest feed conversion ratio was found in the control group while the highest was detected at 15‰ salinity. On the other hand, decreasing trend of specific growth and average growth rate were observed in A. testudineus fingerlings from 0 to 15‰ salinity. Significantly higher specific growth rate and average growth rate were detected in A. testudineus fingerlings reared at 0 - 6‰ salinity (p < 0.05). The present study suggests that Climbing Perch fingerlings can be reared at fresh water growth rates in coastal water with salinity up to 6‰.Dhaka Univ. J. Biol. Sci. 25(1): 65-73, 2016

scholarly journals The rebirth and evolution of Bezymianny volcano, Kamchatka after the 1956 sector collapse

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Alina V. Shevchenko ◽  
Viktor N. Dvigalo ◽  
Thomas R. Walter ◽  
Rene Mania ◽  
Francesco Maccaferri ◽  
...  
Keyword(s):  
Growth Rate ◽  
Numerical Modeling ◽  
Volcanic Activity ◽  
Summit Crater ◽  
Sector Collapse ◽  
Average Growth Rate ◽  
Average Growth ◽  
Bezymianny Volcano ◽  
Lava Domes

Abstract Continued post-collapse volcanic activity can cause the rise of a new edifice. However, details of such edifice rebirth have not been documented yet. Here, we present 7-decade-long photogrammetric data for Bezymianny volcano, Kamchatka, showing its evolution after the 1956 sector collapse. Edifice rebirth started with two lava domes originating at distinct vents ~400 m apart. After 2 decades, activity became more effusive with vents migrating within ~200 m distance. After 5 decades, the activity focused on a single vent to develop a stratocone with a summit crater. We determine a long-term average growth rate of 26,400 m3/day, allowing us to estimate the regain of the pre-collapse size within the next 15 years. Numerical modeling explains the gradual vents focusing to be associated with loading changes, affecting magma pathways at depth. This work thus sheds light on the complex regrowth process following a sector collapse, with implications for regrowing volcanoes elsewhere.

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