Reduction of crystal size of silicalite-1 synthesized in fluoride-containing media via multi-stage heating with intermediate stirring

Phosphorus (P) recovery from urine is affected by various parameters. This study evaluates the effects of hydraulic retention time (HRT) and seed material on P recovery and crystal size in an air-agitated reactor. Results show that ortho-phosphate removal and struvite recovery efficiencies were 96.3% and 89.5%, and 97.1% and 93.0%, after five runs of HRTs of 1 and 2 h, respectively. Low loss of crystals from effluent urine solutions indicates high struvite recovery efficiency and is correlated with the structure and design of the reactor. The average particle size decreased from 40.0 to 31.7 μm as the HRT increased from 1 to 2 h. The two types of seed materials (zeolite and molecular sieve) did not affect the ortho-phosphate removal efficiency but affected the struvite crystal size. In particular, multi-stage addition of zeolites increased the average crystal size from 33.7 to 57.0 μm.

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Investigation of irradiation-induced nucleation processes in silicon and germanium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137495 ◽

1995 ◽

Vol 53 ◽

pp. 224-225

Author(s):

Harry A. Atwater ◽

C.M. Yang ◽

K.V. Shcheglov

Keyword(s):

Room Temperature ◽

Crystal Size ◽

Initial Distribution ◽

Engineering Control ◽

Size Evolution ◽

Silicon And Germanium ◽

Ge Quantum Dot ◽

And Control ◽

Germanium Quantum Dots ◽

Kinetics Of

Studies of the initial stages of nucleation of silicon and germanium have yielded insights that point the way to achievement of engineering control over crystal size evolution at the nanometer scale. In addition to their importance in understanding fundamental issues in nucleation, these studies are relevant to efforts to (i) control the size distributions of silicon and germanium “quantum dots𠇍, which will in turn enable control of the optical properties of these materials, (ii) and control the kinetics of crystallization of amorphous silicon and germanium films on amorphous insulating substrates so as to, e.g., produce crystalline grains of essentially arbitrary size.Ge quantum dot nanocrystals with average sizes between 2 nm and 9 nm were formed by room temperature ion implantation into SiO2, followed by precipitation during thermal anneals at temperatures between 30°C and 1200°C[1]. Surprisingly, it was found that Ge nanocrystal nucleation occurs at room temperature as shown in Fig. 1, and that subsequent microstructural evolution occurred via coarsening of the initial distribution.

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Planning and Search in Multi-Stage Risky Decision Making

PsycEXTRA Dataset ◽

10.1037/e520602012-728 ◽

2011 ◽

Author(s):

Jared Hotaling ◽

Jerry Busemeyer ◽

Richard Shiffrin

Keyword(s):

Decision Making ◽

Risky Decision Making ◽

Risky Decision ◽

Multi Stage

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Pengaruh Pendopingan Karbon Terhadap Struktur Kristal dan Morfologi TIO2

Talenta Conference Series Science and Technology (ST) ◽

10.32734/st.v2i2.492 ◽

2019 ◽

Vol 2 (2) ◽

Author(s):

Frastica Deswardani ◽

Helga Dwi Fahyuan ◽

Rimawanto Gultom ◽

Eif Sparzinanda

Keyword(s):

Thin Film ◽

Crystal Structure ◽

Grain Size ◽

Tio2 Thin Film ◽

Crystal Size ◽

Diffraction Peak ◽

Carbon Doping ◽

Tio2 Anatase ◽

Spray Method ◽

Carbon Analysis

Telah dilakukan penelitian mengenai pengaruh konsentrasi doping karbon pada lapisan tipis TiO2 yang ditumbuhkan dengan metode spray terhadap struktur kristal dan morfologi TiO2. Hasil karakterisasi SEM menunjukkan bahwa penambahan doping karbon dapat meningkatkan ukuran butir. Lapisan TiO2 doping karbon 8% diperoleh ukuran butir terbesar adalah 1.35 μm, sedangkan ukuran tekecilnya adalah 0.45 μm. Sementara itu, untuk lapisan tipis TiO2 didoping karbon 15% memiliki ukuran butir terbesar yaitu 1.76 μm dan terkecil 0.9 μm. Hasil XRD menunjukkan seluruh puncak difraksi lapisan tipis TiO2 dengan doping karbon 8% dan 15% merupakan TiO2 anatase. Ukuran kristal lapisan TiO2 didoping karbon 8% diperoleh sebesar 638,08 Å dan untuk pendopingan 15% karbon ukuran kristal lapisan tipis TiO2 adalah 638,09 Å, hal ini menunjukkan ukuran kristal kedua sampel tidak mengalami perubahan yang signifikan. TiO2 thin film with carbon doping has been successfully grown by spray method. The research on the effect of carbon doping on crystal structure and morfology of TiO2 has been prepared by varying carbon concentration (8% and 15% carbon). Analysis of SEM showed that the addition of carbon may increase the grain size. Thin film of TiO2 doped carbon 8% has the largest grain size 1.35 μm, while the smallest grain size is 0.45 μm. Meanwhile, for thin film TiO2 doped carbon 15% has the largest grain size 1.76 μm and smallest 0.9 μm. The XRD results showed the entire diffraction peak of thin film TiO2 doped carbon 8% and 15% were TiO2 anatase. The crystal size of thin film TiO2 doped carbon 8% was obtained at 638.08 Å and for thin film TiO2 doped carbon 15% the crystalline size of TiO2 thin film was 638.09 Å, this shows that the crystal size of both samples did not change significantly.

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Effects of Cooking Oil Subsidy Removals on Related Markets in Malaysia: A Comparative Static, Multicommodity, Multi Stage Production Approach

International Journal of Management Studies ◽

10.32890/ijms.18.2.2011.10351 ◽

2011 ◽

Author(s):

Jamal Othman ◽

Yaghoob Jafari

Keyword(s):

Equilibrium Model ◽

Comparative Statics ◽

Partial Equilibrium ◽

Cooking Oil ◽

Multi Stage ◽

Supply Factor ◽

Partial Equilibrium Model ◽

Factor Markets ◽

Input Markets ◽

Production Approach

Malaysia is contemplating removal of most of her subsidy support measures including subsidies on cooking oil which is largely palm oil based. This paper aims to examine the effects of cooking oil subsidy removals on the competitiveness of the oil palm subsector and related markets. This is done by developing and applying a comparative static, multi-commodity, partial equilibrium model with multi-stages of production function for the Malaysian perennial crops subsector which explicitly links different stages of production, primary and intermediate input markets, trade, and policy linkages. Results partly suggest that export of cooking oil will increase by 0.2 per cent due to a 10 per cent cooking oil subsidy reduction, while domestic output of cooking oil may eventually see a net decline of 1.97 per cent. The results clearly point out that the effect of reducing cooking oil subsidies is relatively small at the upstream levels and therefore it only induces minute effects on factor markets. Consequently, the market for other agricultural crops is projected to change very marginally. Keywords: Multicomodity, comparative statics, partial equilibrium model, output supply-factor markets linkages, effects of cooking oil subsidy removals.

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IMPACT ASSESSMENT OF AGRICULTURAL TRANSFORMATION PROJECT ON PRODUCTIVITY AND POVERTY AMONG RICE FARMERS IN KANO STATE, NIGERIA.

FUDMA Journal of Sciences ◽

10.33003/fjs-2020-0402-234 ◽

2020 ◽

Vol 4 (2) ◽

pp. 392-400

Author(s):

O. S. Balogun ◽

M. A. Damisa ◽

O. Yusuf ◽

O. L. Balogun

Keyword(s):

Sampling Method ◽

Insect Pests ◽

Study Data ◽

Average Treatment Effect ◽

Descriptive Statistics ◽

Rice Farmers ◽

Agricultural Transformation ◽

Multi Stage ◽

Significant Difference ◽

Late Model

The study was carried out to examine the effect of agricultural transformation on the beneficiary’s productivity and poverty of rice farmers in Kano State Nigeria. A multi-stage sampling method was employed to select 571 respondents for the study. Data were collected through structured questionnaires on respondent’s income, input and output quantities as well as their expenditures. Data were analysis using descriptive statistics, Foster-Greer-Thorbecke (FGT), Propensity score matching and LATE model. Results from the study shows that respondents productivity revealed a significant difference of about 127 kg/ha in rice productivity between participants and non-participants. Also, the LATE estimates revealed an average treatment effect ATE0 of about 222.98kg/ha. Furthermore, the project had a significant effect N11, 321.4 on the participant’s consumption expenditure than the non-participants N9980.60. Moreover, participants were, able to increase their household total expenditures by N34780 per annum. Fluctuations of input/output prices insect pests and inadequate extension visits were all the major constraints faced by the farmers. It was recommended that farmers’ information and sensitization system should be overhauled and improved. Also, attention should be given to well organize extension visits for the farmers from stake holders

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Radiofrequency ablation of colorectal liver metastases

Perspectives in Surgery ◽

10.33699/pis.2019.98.10.399-403 ◽

2019 ◽

Vol 98 (10) ◽

Keyword(s):

Radiofrequency Ablation ◽

Liver Resection ◽

Liver Metastases ◽

Colorectal Liver Metastases ◽

Survival Rates ◽

Postoperative Mortality ◽

Disease Free Survival ◽

Female Ratio ◽

Liver Resections ◽

Multi Stage

Introduction: Radical liver resection is the only method for the treatment of patients with colorectal liver metastases (CLM); however, only 20–30% of patients with CLMs can be radically treated. Radiofrequency ablation (RFA) is one of the possible methods of palliative treatment in such patients. Methods: RFA was performed in 381 patients with CLMs between 01 Jan 2001 and 31 Dec 2018. The mean age of the patients was 65.2±8.7 years. The male to female ratio was 2:1. Open laparotomy was done in 238 (62.5%) patients and the CT-navigated transcutaneous approach was used in 143 (37.5%) patients. CLMs <5 cm (usually <3 cm) in diameter were the indication for RFA. We used RFA as the only method in 334 (87.6%) patients; RFA in combination with resection was used in 36 (9.4%), and with multi-stage resection in 11 (3%) patients. We performed RFA in a solitary CLM in 170 (44.6%) patients, and in 2−5 CLMs in 211 (55.6%) patients. We performed computed tomography in each patient 48 hours after procedure. Results: The 30-day postoperative mortality was zero. Complications were present in 4.8% of transcutaneous and in 14.2% of open procedures, respectively, in the 30-day postoperative period. One-, 3-, 5- and 10-year overall survival rates were 94.8, 66.8, 43.9 and 16.6%, respectively, in patients undergoing RFA, and 90.6, 69.1, 52.8 and 39.2%, respectively, in patients with liver resections. Disease free survival was 63.2, 30.1, 18.4 and 13.1%, respectively, in the same patients after RFA, and 71.1, 33.3, 22.8 and 15.5%, respectively, after liver resections. Conclusion: RFA is a palliative thermal ablation method, which is one of therapeutic options in patients with radically non-resectable CLMs. RFA is useful especially in a non-resectable, or resectable (but for the price of large liver resection) solitary CLM <3 cm in diameter and in CLM relapses. RFA is also part of multi-stage liver procedures.

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