scholarly journals Production Rate of SiO Gas from Industrial Quartz and Silicon

2021 ◽  
Author(s):  
Caroline Sindland ◽  
Merete Tangstad
Keyword(s):  
Production Rate ◽  
Reaction Rate ◽  
Impurity Content ◽  
Melting Rate ◽  
Transformation Rate ◽  
Isothermal Heat Treatment ◽  
Degree Of Reaction ◽  
Significant Difference ◽  
Different Types ◽  
Reaction Constant

AbstractThe production rate of SiO gas from industrial quartz and silicon has been investigated by isothermal heat treatment experiments. Mixtures of silicon and different quartz samples have been heated to temperatures ranging from 1650 °C to 1950 °C and held for 30 to 120 minutes before cooling. The weight loss of each sample has been correlated to degree of reaction and a model for the reaction rate of Si + SiO2 has been developed based on these values. Five different types of industrial quartz were used in the experiments. No significant difference was found in their reaction rate, even though there are large variations in impurity content, melting rate, decrepitation, and phase transformation rate of each sample. Further on, it is shown that the reaction rate of silicon mixed with various types of quartz can be described by an Arrhenius equation: $${{\rm {d}}\alpha /{\rm {d}}t = k_0 \, A \, {\rm {exp}} (- Q / RT)}$$ d α / d t = k 0 A exp ( - Q / R T ) . A reaction constant (k0) equal to $${6.25 \, 10^8 {\rm {g}}\, {\rm {s}}^{-1}\, {\rm{m^{-2}}}}$$ 6.25 10 8 g s - 1 m - 2 and an activation energy (Q) equal to $${557\, {\rm {kJ \, mol^{-1}}}}$$ 557 kJ mol - 1 were obtained by linear regression. The degree of reaction ($${\alpha }$$ α ) is shown to be increasing with available reaction area, temperature, and time.

Households Discrimination in School Enrolment in Pakistan: Does gender matter?

2018 ◽  
Vol 2 (1) ◽  
pp. 29-36
Author(s):  
Ali Muhammad ◽  
Zahoor Ul Haq ◽  
Imad Khan
Keyword(s):  
Low Income ◽  
Gender Discrimination ◽  
Rural Areas ◽  
Gender Disparity ◽  
School Enrollment ◽  
Female Education ◽  
Public And Private ◽  
Significant Difference ◽  
Different Types ◽  
Socio Economic Factors

This study uses Pakistan Social and Living Measurement Survey 2016 to study gender discrimination in school enrollment across the four provinces of Pakistan using bi-variate analysis. Results show that there is highly significant difference between male and female education in rural areas (x^2=4940.50 and p<0.05). Analysis indicate that gender disparity in enrollment is significantly higher in low income households (x^2=115.468 and P<0.05). The study also showed that as compared to male, fewer female are enrolled in both public and private sectors. Hence, socio-economic factors play important role in making decision about children enrollment in different types of school. The study recommends that government to take appropriate steps to reduce gender discrimination in school enrollment by offering subsidy on female education in the country.

Using Histological and Chemical Methods for Detection of Unauthorized Tissues Addition in Emulsion Type Meat Product

2020 ◽  
Keyword(s):  
Vascular Tissue ◽  
Meat Product ◽  
Calcium Content ◽  
Processed Meat ◽  
Low Protein ◽  
Significant Difference ◽  
Different Types ◽  
Plant Stem ◽  
High Level ◽  
Reliable Methods

Total twenty different processed meat plant producing emulsion type sausage were histologically and chemically examined for detection of adulteration with unauthorized tissues. Results revealed that samples were adulterated with different types of animal tissues included; hyaline cartilage, tendon, spongy bone, peripheral nerve trunk, basophilic matrix, lymphatic tissue, fascia, fibrocartilage and vascular tissue. Moreover, these samples were adulterated Also, adulterated with plant tissue included; plant stem, leaves and root. Chemical analysis showed a significant difference in their chemical composition (moisture, fat, protein, ash and calcium) content. Moisture and fat content varied around the permissible limit of E.S.S. while low protein, high ash and calcium content was detected in the examined samples. Therefore, Histological and chemical examinations can be used as reliable methods to detect adultration using unauthorized addition of both animal and plant tissues in processed meat product samples which revealed a high level of falsification.

scholarly journals Snail mucus from the mantle and foot of two land snails, Lissachatina fulica and Hemiplecta distincta, exhibits different protein profile and biological activity

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nattaphop Noothuan ◽  
Kantamas Apitanyasai ◽  
Somsak Panha ◽  
Anchalee Tassanakajon
Keyword(s):  
Biological Activities ◽  
Protein Pattern ◽  
Protein Profile ◽  
Antibacterial Properties ◽  
Biological Properties ◽  
Specific Protein ◽  
Land Snails ◽  
Snail Species ◽  
Significant Difference ◽  
Different Types

Abstract Objective Snails secrete different types of mucus that serve several functions, and are increasingly being exploited for medical and cosmetic applications. In this study, we explored the protein pattern and compared the biological properties of the mucus secreted from the mantle collar and foot of two snail species, Lissachatina fulica and Hemiplecta distincta. Result Protein profile showed a different pattern between the two species and between the two secretory parts. The mantle-specific protein bands were further characterized and among them was an antibacterial protein, achacin. Accordingly, the mucus from the mantle exhibited the higher antibacterial activity than that from the foot in both snail species. The mucus from H. distincta, first reported here, also showed antibacterial properties, but with a lower activity compared to that for L. fulica. Snail mucus also exhibited anti-tyrosinase activity and antioxidant activity but with no significant difference between the foot and mantle mucus. These results indicate some different protein compositions and biological activities of snail slime from the mantle and foot, which might be associated with their specific functions in the animal and are useful for medical applications.

scholarly journals Effect of Different SiO2 Polymorphs on the Reaction Between SiO2 and SiC in Si Production

2021 ◽  
Vol 52 (2) ◽  
pp. 792-803
Author(s):  
Marit Buhaug Folstad ◽  
Eli Ringdalen ◽  
Halvard Tveit ◽  
Merete Tangstad
Keyword(s):  
Amorphous Silica ◽  
Reaction Rate ◽  
Reduction Reaction ◽  
Minor Effect ◽  
Target Temperature ◽  
Heating Rates ◽  
Significant Difference ◽  
Sio2 Polymorphs ◽  
A Minor ◽  
Final Composition

AbstractThis work investigates the phase transformations in silica (SiO2) during heating to a target temperature between 1700 °C and 1900 °C and the effect of SiO2 polymorphs on the reduction reaction 2SiO2 + SiC = 3SiO + CO in silicon production. Different heating rates up to target temperature have been used to achieve the different compositions of quartz, amorphous silica and cristobalite. The different heating rates had a minor effect on the final composition, and longer time at temperatures > 1400 °C were necessary to achieve greater variations in the final composition. Heating above the melting temperature gave more amorphous silica and less cristobalite, as amorphous silica also may form from β-cristobalite. Isothermal furnace experiments were conducted to study the extent of the reduction reaction. This study did not find any significant difference in the effects of quartz, amorphous silica or cristobalite. Increased temperature from 1700 °C to 1900 °C increased the reaction rate.

Analysis of Support for Parents in Raising Children with Dyslexia

2020 ◽  
pp. 0192513X2094892
Author(s):  
Athira Amira Abd Rauf ◽  
Maizatul Akmar Ismail ◽  
Vimala Balakrishnan ◽  
Loh Sau Cheong ◽  
Novia Indriaty Admodisastro ◽  
...  
Keyword(s):  
Marital Status ◽  
Self Esteem ◽  
Peer To Peer ◽  
Government Support ◽  
Anova Analysis ◽  
Raising Children ◽  
The Social ◽  
Significant Difference ◽  
Different Types ◽  
One Way Anova

The parents of children with dyslexia often experience more parenting stress and depressive symptoms compared to other parents. Studies have shown that supporting and encouraging such parents help in reducing their frustrations, fear, anger, and low self-esteem towards their children. The purpose of this study was to identify and examine the different types of support needed by the parents of children with dyslexia and to explore the relationships between the required support with the parents’ marital status. Fifty questionnaires were distributed to the parents of children with dyslexia and analyzed. The findings showed that the type of support needed for parents of children with dyslexia could be grouped into social, peer-to-peer, financial, and government support. Furthermore, the analysis indicated that there were no significant differences between the social (p = 0.4014), peer-to-peer (p = 0.5020), and government (p = 0.7121) support with parents’ marital status. However, based on one-way ANOVA analysis, there was a significant difference found between the parents’ marital status and financial support (p = 0.0241). Accordingly, it is anticipated that the implication of this research could be used as a guide and a reference for supporting and encouraging parents of children with dyslexia and other learning disabilities.

Comparison of two types of inocula during acclimation and stable operation for nitrophenol biodegradation in an anaerobic-aerobic SBR

2006 ◽  
Vol 54 (10) ◽  
pp. 39-45
Author(s):  
A. Vargas ◽  
D. González ◽  
A. Estival ◽  
G. Buitrón
Keyword(s):  
Wastewater Treatment ◽  
Treatment Plant ◽  
The Other ◽  
Stable Operation ◽  
Reaction Phase ◽  
Toxic Compound ◽  
Anaerobic Wastewater Treatment ◽  
Significant Difference ◽  
Different Types ◽  
Batch Bioreactors

This work presents a comparison of two inocula used for the acclimation of two anaerobic-aerobic sequencing batch bioreactors used for toxic wastewater treatment. The bioreactors were acclimated with different types of sludge: one coming from an anaerobic wastewater treatment plant and the other one from a conventional aerobic activated sludge plant. The model toxic compound was p-nitrophenol, which is reduced to p-aminophenol during the initial anaerobic phase of the reaction, and later mineralized during a posterior aerated reaction phase. Biodegradation of the compounds was monitored using UV/Vis spectrophotometry. After acclimation stabilization of the sludge and of the process was also monitored. Results show that there is no significant difference in acclimation times and stability of the process between the two employed inocula, and thus an originally anaerobic inoculum presents no apparent advantage over a more easily accessible aerobic one.

A radiopathological classification of dural tail sign of meningiomas

2012 ◽  
Vol 117 (4) ◽  
pp. 645-653 ◽  
Author(s):  
Song-tao Qi ◽  
Yi Liu ◽  
Jun Pan ◽  
Silky Chotai ◽  
Lu-xiong Fang
Keyword(s):  
Tumor Cells ◽  
Histopathological Examination ◽  
Who Grade ◽  
Simpson Grade ◽  
Mri Studies ◽  
Dural Tail Sign ◽  
Significant Difference ◽  
Different Types ◽  
Dural Tail

Object The completeness of meningioma resection depends on the resection of dura mater invaded by the tumor. The pathological changes of the dura around the tumor can be interpreted by evaluating the dural tail sign (DTS) on MRI studies. The goal of this study was to clarify the pathological characteristics of the DTSs, propose a classification based on the histopathological and radiological correlation, and identify the invasive range of tumor cells in different types of DTS. Methods The authors retrospectively reviewed 179 patients with convexity meningiomas who underwent Simpson Grade I resection. All patients underwent an enhanced MRI examination preoperatively. The convexity meningiomas were dichotomized into various subtypes in accordance with the 2007 WHO classification of tumors of the CNS, and the DTS was identified based on the Goldsher criteria. The range of resection of the involved dura was 3 cm from the base of the tumor, which corresponded with the length of DTS on MRI studies. Histopathological examination of dura at 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 cm from the base of the tumor was conducted, and the findings were correlated with the preoperative MRI appearance of the DTS. Results A total of 154 (86%) of 179 convexity meningiomas were classified into WHO Grade I subtype, including transitional (44 [28.6%] of 154), meningothelial (36 [23.4%] of 154), fibrous (23 [14.9%] of 154), psammomatous (22 [14.3%] of 154), secretory (10 [6.5%] of 154), and angiomatous (19 [12.3%] of 154). The other 25 (14%) were non–Grade I (WHO) tumors, including atypical (12 [48%] of 25), anaplastic (5 [20%] of 25), and papillary (8 [32%] of 25). The DTS was classified into 5 types: smooth (16 [8.9%] of 179), nodular (36 [20.1%] of 179), mixed (57 [31.8%] of 179), symmetrical multipolar (15 [8.4%] of 179), and asymmetrical multipolar (55 [30.7%] of 179). There was a significant difference in distribution of DTS type between Grade I and non–Grade I tumors (p = 0.004), whereas the difference was not significant among Grade I tumors (0.841) or among non–Grade I tumors (p = 0.818). All smooth-type DTSs were encountered in Grade I tumors, and the mixed DTS (52 [33.8%] of 154) was the most common type in these tumors. Nodular-type DTS was more commonly seen in non–Grade I tumors (12 [48%] of 25). Tumor invasion was found in 88.3% (158 of 179) of convexity meningiomas, of which the range of invasion in 82.3% (130 of 158) was within 2 cm and that in 94.9% (150 of 158) was within 2.5 cm. The incidence of invasion and the range invaded by tumor cells varied in different types of DTS, and differences were statistically significant (p < 0.001). Conclusions Nodular-type DTS on MRI studies might be associated with non–Grade I tumors. The range of dural resection for convexity meningiomas should be 2.5 cm from the tumor base, and if this extent of resection is not feasible, the type of DTS should be considered. However, for skull base meningiomas, in which mostly Simpson Grade II resection is achieved, the use of this classification should be further validated. The classification of DTS enables the surgeon to predict preoperatively and then to achieve the optimal range of dural resection that might significantly reduce the recurrence rate of meningiomas.

scholarly journals Differential Diffusivity Effects in Reactive Convective Dissolution

Fluids ◽  
2018 ◽  
Vol 3 (4) ◽  
pp. 83 ◽  
Author(s):  
V. Loodts ◽  
H. Saghou ◽  
B. Knaepen ◽  
L. Rongy ◽  
A. De Wit
Keyword(s):  
Diffusion Coefficients ◽  
Reaction Rate ◽  
Chemical Species ◽  
Mixing Zone ◽  
Simultaneous Presence ◽  
Dynamic Effects ◽  
Density Profiles ◽  
Differential Diffusion ◽  
Different Types ◽  
Double Diffusive

When a solute A dissolves into a host fluid containing a reactant B, an A + B → C reaction can influence the convection developing because of unstable density gradients in the gravity field. When A increases density and all three chemical species A, B and C diffuse at the same rate, the reactive case can lead to two different types of density profiles, i.e., a monotonically decreasing one from the interface to the bulk and a non-monotonic profile with a minimum. We study numerically here the nonlinear reactive convective dissolution dynamics in the more general case where the three solutes can diffuse at different rates. We show that differential diffusion can add new dynamic effects like the simultaneous presence of two different convection zones in the host phase when a non-monotonic profile with both a minimum and a maximum develops. Double diffusive instabilities can moreover affect the morphology of the convective fingers. Analysis of the mixing zone, the reaction rate, the total amount of stored A and the dissolution flux further shows that varying the diffusion coefficients of the various species has a quantitative effect on convection.

scholarly journals An exertion of enhance milk yield of native Pabna cattle through using different types of calcium salt of fatty acid

2018 ◽  
Vol 15 (2) ◽  
pp. 137-146 ◽  
Author(s):  
D Yeasmin ◽  
N Islam ◽  
NR Sarker ◽  
N Huda ◽  
A Habib ◽  
...  
Keyword(s):  
Body Weight ◽  
Fatty Acid ◽  
Milk Yield ◽  
Calcium Salt ◽  
Bos Indicus ◽  
Mustard Oil ◽  
Initial Body Weight ◽  
Significant Difference ◽  
Different Types ◽  
Concentrate Mixture

Keeping consideration on increasing quality milk production through addition of conventional fat, an experiment accords CRD design was conducted at Bangladesh Livestock Research Institute, Savar, Dhaka for a period of 30 days including 5 days of digestibility trial. Twenty lactating Pabna cattle of average 250.1 ± 13.64 kg (Bos indicus) of initial body weight with average milk yield of 2.88 ± 0.38 kg were selected and divided into four groups randomly having five cows in each. The imposed treatments were T0, T1, T2, and T3; in where To= German grass + Concentrate mixture without Ca salt of fatty acid + 2.5 % DCP, T1= German grass + Concentrate mixture + 2.5 % soybean based Ca salt of fatty acid, T2= German grass + Concentrate mixture + 2.5 % mustard based Ca salt of fatty acid and T3= German grass + Concentrate mixture + 2.5% palm-oil based Ca salt of fatty acid. The result showed that, calcium salt of fatty acid influenced to increase of milk yield significantly among (P<0.001) the treatments; in where highest yield gained in T1 (3.53 kg d-1) followed by T2, T0 and T3 (3.33, 2.44 and 2.24, respectively). Besides this, all other parameters analytically examined in this experiment i.e. intake, apparent digestibility, gained body weight and chemical composition of milk showed non-significant difference among the treatments. From the analytical value and discussion, it may be suggested that, calcium salt of fatty acid formulated from soybean oil or mustard oil could be used for enhancing better quality milk yield.SAARC J. Agri., 15(2): 137-146 (2017)

scholarly journals DIFFERENT APPROACHES OF CLIENTS AND CONSULTANTS TO CONTRACTORS’ QUALIFICATION AND SELECTION

2005 ◽  
Vol 11 (4) ◽  
pp. 267-276 ◽  
Author(s):  
Mehmedali Egemen ◽  
Abdulrezak N. Mohamed
Keyword(s):  
Construction Industry ◽  
Selection Processes ◽  
Significant Difference ◽  
Different Types ◽  
Almost All ◽  
High Willingness

Nowadays, clients are the dominant groups in almost all types of industries. However, the construction industry is unique and consultants, as representatives of clients, are very important figures in this industry as well. By presenting survey findings of 91 clients and 50 consultants, this study reveals clients’ and consultants’ differing expectations of contracting organisations during contractor qualification and selection. The study has clearly confirmed the fact that consultants’ perspectives are rather different and their contractors’ expectations of their clients vary very significantly from the clients themselves. Furthermore, significantly different results were found even among different types of consultants and different categories of clients. Moreover, this study showed that both clients and consultants had high willingness to continue working with the same contractor in possible future works assuming they are satisfied with the previous works. The criteria, which contribute to achieving full client and/or consultant satisfaction and hence lead to possible repetitive works are identified and the results showed the existence of significant difference between clients and consultants perspectives regarding this issue as well. The framework presented within this paper aims to help the contracting organisations to compare and recognise the different approaches and perceptions of both clients and consultants during contractor qualification and selection processes. The contracting organisations in the related sectors will be able to use the framework provided within this study to recognise the overall demand in a more complete and better manner and hence formulate or modify strategies accordingly.

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