The chemical and mineralogical composition of bauxite deposits is a key factor in the profitability of refining processes. The study of bauxites from the Saföfö site has assessed variations in chemical and m...The chemical and mineralogical composition of bauxite deposits is a key factor in the profitability of refining processes. The study of bauxites from the Saföfö site has assessed variations in chemical and mineralogical composition under various conditions, as well as the optimum conditions for their exploitation. The methodologies used in this study include experimental methods for determining moisture content, chemical composition, mineralogical composition, and specific density of bauxite. The results show significant variation in moisture content among the bauxite samples, with values ranging from 2.90% to 17.80%. The silica percentages in the samples range from 1.69% to 8.14%, while alumina percentages vary from 36.81% to 54.03%. After calcination, alumina oxide percentages range from 40% to 75%. After chemical activation, alumina oxides Al2O3 range from 40% to over 50%. Gibbsite is the most abundant mineral, accounting for about 60% - 70% of the total composition of the bauxite samples. Samples A to F have bulk densities varying between approximately 3.6 and 3.9. Sample B has the highest density, around 3.9, while sample C has the lowest, at around 3.5. Bauxite mining at the Saföfö site offers significant potential for the alumina industry, provided appropriate processing methods are selected to maximize quality and profitability while minimizing environmental impact.展开更多
A late fall frost may significantly affect sugar crops’ stem sugar composition, yield and juice quality for biofuel and bioproduct manufacture. Research on the effects of late fall frost in sugarcane is well document...A late fall frost may significantly affect sugar crops’ stem sugar composition, yield and juice quality for biofuel and bioproduct manufacture. Research on the effects of late fall frost in sugarcane is well documented, but information is lacking for sweet sorghum. Three and six commercial cultivars of sugarcane and sweet sorghum, respectively, were selected and evaluated for exposure to a late fall frost (-2.8°C) in Griffin, Georgia, USA. Under the same controlled environmental conditions in a screen house, the late fall frost induced more damage to sugarcane than sweet sorghum stems. The frost caused damage to sugarcane tissue and for juice to exude from stems, whereas similar behavior was not observed for sweet sorghum. In both sugarcane and sweet sorghum, the glucose/fructose ratio was significantly reduced, but this change may not be totally directly related to the frost effect. Overall, these initial results suggest that sweet sorghum may have a better tolerance to fall frost than sugarcane. Two sweet sorghum cultivars, Grassl and M81E, responded well to the late fall frost, and they can possibly be used as feedstocks for biofuel/bioproduct manufacture in areas susceptible to frosts including northern regions of the Southeastern US.展开更多
A methodology for calculating the thermal conductivity of soils and rocks is developed which takes into account their origin and mineralogical composition.This method utilizes three approaches.One is founded on the st...A methodology for calculating the thermal conductivity of soils and rocks is developed which takes into account their origin and mineralogical composition.This method utilizes three approaches.One is founded on the structural modeling of contact heat interaction between particles and fills and estimates the statistical probability distribution of the particles in the volume of the medium.The second approach analyses perturbation to the temperature field of the matrix medium by ellipsoidal inclusions.The third approach is to find the mean thermal conductivity of the solid skeleton in the universal model at different composition of rock-forming minerals.展开更多
In this paper the Expendable Pattern Casting with dry sand Vacuum(EPC-V) process is used to manufacture iron matrix composites with tungsten carbide particle.Microstructures of the composites layers were analyzed.The ...In this paper the Expendable Pattern Casting with dry sand Vacuum(EPC-V) process is used to manufacture iron matrix composites with tungsten carbide particle.Microstructures of the composites layers were analyzed.The abrasive wear resistance of the composites layers were tested and compared with that of high chromium cast iron.The results show that the iron matrix composites with tungsten carbide particle have high hardness.The abrasive wear resistance of composites with tungsten carbide particle is higher than that of high chromium cast iron.The properties of the matrix materials have been improved remarkably.展开更多
We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty ...We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty bounded closed and convex values, are an affine function.展开更多
Wheat germ is reckoned valuable healthful functional food. The present investigation was performed to assess nutritional status of wheat biscuits and wheat germ fortified biscuits. Study included determination of gros...Wheat germ is reckoned valuable healthful functional food. The present investigation was performed to assess nutritional status of wheat biscuits and wheat germ fortified biscuits. Study included determination of gross chemical composition, caloric value, minerals (Mn, Ca, Fe, Cu, P, Na and K), vitamins (C, Folic acid, A, and E), and amino acid composition of wheat biscuits and 15%, 20% wheat germ fortified biscuits. Likewise physical and sensory characteristics of studied biscuits were assessed. The data revealed that 20% wheat germ fortified biscuits proved to be nutritious functional healthful food. It improved both physical, sensory characteristics and recorded the highest crude protein (12.20%), crude fiber (2%), and the least fat (9.63%), moisture (3.01%), and caloric value (436.31 Kcal/100g). While it recorded the highest Mn and Cu contents as well as increased vitamins C, Folic acid, A, and E. Besides, 20% wheat germ fortified biscuits increased all the eight essential amino acids contents resulting in an improvement of the nutritive value of wheat biscuits. Therefore it could be recommended for caloric reduced diets for obese and overweight persons. Likewise, it should be increasing interest as an ingredient in the industry as functional and healthy foods formulations as biscuits, bread and cakes.展开更多
Although animal proteins provide indispensable amino acids that the body requires for normal growth, maintenance and function, their expensiveness makes them unaffordable especially for most families in the developing...Although animal proteins provide indispensable amino acids that the body requires for normal growth, maintenance and function, their expensiveness makes them unaffordable especially for most families in the developing countries. This has given impetus to extensive research into under-utilized protein-rich oilseeds such as sorrel as possible alternate sources of good quality protein for tackling the challenge of protein-energy malnutrition which is fast becoming a global challenge. Sorrel seed may hold great potentials as a source of good quality protein, however the presence of hard seed coat, bitter after-taste and associated antinutritional factors have limited its use as protein supplement for humans and food ingredient. This study therefore compared the effect of dehulling sorrel seed to boiling, germination and roasting. This was with the aim of enhancing its utilization as protein source for human nutrition and functional ingredient in food product development. Flours obtained were analyzed for their proximate, mineral, antinutrient, amino and fatty acids composition;in vitro starch and protein digestibility, and functional and antioxidative properties. Protein content (ranged from 24.93% - 32.91%) significantly increased due to processing;dehulling alone accounted for a percentage increase of 32.01%. Similarly, dehulling increased all essential amino acids (except isoleucine and valine) at percentage which ranged from 3.63% - 61.17% whereas other processing methods caused significant reductions. Lysine, leucine, valine, arginine and phenylalanine were the most abundant essential amino acids, while methionine and cystine were the first and second limiting amino acids. Palmitic, linoleic, oleic and stearic acids were the most abundant fatty acids. Mineral composition was K > Ca > Mg > Na > Fe > Zn > Mn. Dehulled seed flour had highest in vitro protein digestibility (75.87%). Improved amino acid composition, antioxidative and functional properties of sorrel seed flour due to dehulling may indicate the potential of this flour to serve as a protein supplement and functional ingredient for food product development.展开更多
Group size and composition of blue sheep(Pseudois nayaur)were studied in the Helan Mountains, Ningxia Autonomous Region from November to December 2003.We scanned mountain slopes with binoculars and observed with 20-60...Group size and composition of blue sheep(Pseudois nayaur)were studied in the Helan Mountains, Ningxia Autonomous Region from November to December 2003.We scanned mountain slopes with binoculars and observed with 20-60× spotting-scope. A total of 310 herds of blue sheep and 1 336 individuals were observed during the study period. Blue sheep were frequently seen in small herds of 2 to 8 individuals, which represent 94.8% of total herds observed. Herds consisting of 9 individuals or more represented 5.2%. The largest herd we observed numbered 51 individuals. Mean group size was 4.2 individuals. Blue sheep herds can be divided into three types: male herds (composed solely of males), female herds (consisting of females with or without juveniles of both sexes), and mixed herds (including adult males, females, and subadults).Among the 310 herds, female herds were counted 150 times(48.4%), mixed herds 154 times(49.7%), and male herds 6 times(1.9%). Of 1 336 blue sheep classified by sex and age, adults, subadults and juveniles composed 64.1%,20.8%, and 15.1% respectively. The female:male ratio of adults was 1∶0.73. The ratio of adult females to juveniles was 1∶0.56, which is higher than the ratio recorded in spring (1∶0.43) or summer (1∶0.44).The results showed that the Helan Mountains State Nature Reserve has succeed in protecting blue sheep.展开更多
Objective The Altyn Tagh marks the northern margin of the Qinghai-Tibet Plateau and lies between the Tarim block to the north and the Qaidam block,Qilian Orogen,and Kunlun orogenic belt to the south.The Altyn Tagh reg...Objective The Altyn Tagh marks the northern margin of the Qinghai-Tibet Plateau and lies between the Tarim block to the north and the Qaidam block,Qilian Orogen,and Kunlun orogenic belt to the south.The Altyn Tagh region contains ophiolite,high-to ultrahigh-pressure metamorphic rocks,and igneous rocks.Previous research has virified the occurrence of continental rifting,subduction,slab roll-back,and collision between the Tarim block and Proto-Tethys oceanic plate.Moreover,Kaladaban volcanic rocks are mainly distributed in the north Altyn region.Studies of the magmatic evolution of this region have proposed that Altyn oceanic plate was subducted during the Ordovician(Han et al.,2012;Wang et al.,2017).However,the specific timing and other aspects of the subduction are debated,and an investigation of granite porphyry in the Kaladaban area would improve our understanding of this subduction event.In this study,we present new U-Pb zircon dating result and Sr-Nd isotope composition data for granite porphyry from the North Altyn region.The objective is to constrain the timing of subduction of the North Altyn oceanic plate and establish the petrogenesis and magma source of the granite porphyry.展开更多
文摘The chemical and mineralogical composition of bauxite deposits is a key factor in the profitability of refining processes. The study of bauxites from the Saföfö site has assessed variations in chemical and mineralogical composition under various conditions, as well as the optimum conditions for their exploitation. The methodologies used in this study include experimental methods for determining moisture content, chemical composition, mineralogical composition, and specific density of bauxite. The results show significant variation in moisture content among the bauxite samples, with values ranging from 2.90% to 17.80%. The silica percentages in the samples range from 1.69% to 8.14%, while alumina percentages vary from 36.81% to 54.03%. After calcination, alumina oxide percentages range from 40% to 75%. After chemical activation, alumina oxides Al2O3 range from 40% to over 50%. Gibbsite is the most abundant mineral, accounting for about 60% - 70% of the total composition of the bauxite samples. Samples A to F have bulk densities varying between approximately 3.6 and 3.9. Sample B has the highest density, around 3.9, while sample C has the lowest, at around 3.5. Bauxite mining at the Saföfö site offers significant potential for the alumina industry, provided appropriate processing methods are selected to maximize quality and profitability while minimizing environmental impact.
文摘A late fall frost may significantly affect sugar crops’ stem sugar composition, yield and juice quality for biofuel and bioproduct manufacture. Research on the effects of late fall frost in sugarcane is well documented, but information is lacking for sweet sorghum. Three and six commercial cultivars of sugarcane and sweet sorghum, respectively, were selected and evaluated for exposure to a late fall frost (-2.8°C) in Griffin, Georgia, USA. Under the same controlled environmental conditions in a screen house, the late fall frost induced more damage to sugarcane than sweet sorghum stems. The frost caused damage to sugarcane tissue and for juice to exude from stems, whereas similar behavior was not observed for sweet sorghum. In both sugarcane and sweet sorghum, the glucose/fructose ratio was significantly reduced, but this change may not be totally directly related to the frost effect. Overall, these initial results suggest that sweet sorghum may have a better tolerance to fall frost than sugarcane. Two sweet sorghum cultivars, Grassl and M81E, responded well to the late fall frost, and they can possibly be used as feedstocks for biofuel/bioproduct manufacture in areas susceptible to frosts including northern regions of the Southeastern US.
文摘A methodology for calculating the thermal conductivity of soils and rocks is developed which takes into account their origin and mineralogical composition.This method utilizes three approaches.One is founded on the structural modeling of contact heat interaction between particles and fills and estimates the statistical probability distribution of the particles in the volume of the medium.The second approach analyses perturbation to the temperature field of the matrix medium by ellipsoidal inclusions.The third approach is to find the mean thermal conductivity of the solid skeleton in the universal model at different composition of rock-forming minerals.
文摘In this paper the Expendable Pattern Casting with dry sand Vacuum(EPC-V) process is used to manufacture iron matrix composites with tungsten carbide particle.Microstructures of the composites layers were analyzed.The abrasive wear resistance of the composites layers were tested and compared with that of high chromium cast iron.The results show that the iron matrix composites with tungsten carbide particle have high hardness.The abrasive wear resistance of composites with tungsten carbide particle is higher than that of high chromium cast iron.The properties of the matrix materials have been improved remarkably.
文摘We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty bounded closed and convex values, are an affine function.
文摘Wheat germ is reckoned valuable healthful functional food. The present investigation was performed to assess nutritional status of wheat biscuits and wheat germ fortified biscuits. Study included determination of gross chemical composition, caloric value, minerals (Mn, Ca, Fe, Cu, P, Na and K), vitamins (C, Folic acid, A, and E), and amino acid composition of wheat biscuits and 15%, 20% wheat germ fortified biscuits. Likewise physical and sensory characteristics of studied biscuits were assessed. The data revealed that 20% wheat germ fortified biscuits proved to be nutritious functional healthful food. It improved both physical, sensory characteristics and recorded the highest crude protein (12.20%), crude fiber (2%), and the least fat (9.63%), moisture (3.01%), and caloric value (436.31 Kcal/100g). While it recorded the highest Mn and Cu contents as well as increased vitamins C, Folic acid, A, and E. Besides, 20% wheat germ fortified biscuits increased all the eight essential amino acids contents resulting in an improvement of the nutritive value of wheat biscuits. Therefore it could be recommended for caloric reduced diets for obese and overweight persons. Likewise, it should be increasing interest as an ingredient in the industry as functional and healthy foods formulations as biscuits, bread and cakes.
文摘Although animal proteins provide indispensable amino acids that the body requires for normal growth, maintenance and function, their expensiveness makes them unaffordable especially for most families in the developing countries. This has given impetus to extensive research into under-utilized protein-rich oilseeds such as sorrel as possible alternate sources of good quality protein for tackling the challenge of protein-energy malnutrition which is fast becoming a global challenge. Sorrel seed may hold great potentials as a source of good quality protein, however the presence of hard seed coat, bitter after-taste and associated antinutritional factors have limited its use as protein supplement for humans and food ingredient. This study therefore compared the effect of dehulling sorrel seed to boiling, germination and roasting. This was with the aim of enhancing its utilization as protein source for human nutrition and functional ingredient in food product development. Flours obtained were analyzed for their proximate, mineral, antinutrient, amino and fatty acids composition;in vitro starch and protein digestibility, and functional and antioxidative properties. Protein content (ranged from 24.93% - 32.91%) significantly increased due to processing;dehulling alone accounted for a percentage increase of 32.01%. Similarly, dehulling increased all essential amino acids (except isoleucine and valine) at percentage which ranged from 3.63% - 61.17% whereas other processing methods caused significant reductions. Lysine, leucine, valine, arginine and phenylalanine were the most abundant essential amino acids, while methionine and cystine were the first and second limiting amino acids. Palmitic, linoleic, oleic and stearic acids were the most abundant fatty acids. Mineral composition was K > Ca > Mg > Na > Fe > Zn > Mn. Dehulled seed flour had highest in vitro protein digestibility (75.87%). Improved amino acid composition, antioxidative and functional properties of sorrel seed flour due to dehulling may indicate the potential of this flour to serve as a protein supplement and functional ingredient for food product development.
文摘Group size and composition of blue sheep(Pseudois nayaur)were studied in the Helan Mountains, Ningxia Autonomous Region from November to December 2003.We scanned mountain slopes with binoculars and observed with 20-60× spotting-scope. A total of 310 herds of blue sheep and 1 336 individuals were observed during the study period. Blue sheep were frequently seen in small herds of 2 to 8 individuals, which represent 94.8% of total herds observed. Herds consisting of 9 individuals or more represented 5.2%. The largest herd we observed numbered 51 individuals. Mean group size was 4.2 individuals. Blue sheep herds can be divided into three types: male herds (composed solely of males), female herds (consisting of females with or without juveniles of both sexes), and mixed herds (including adult males, females, and subadults).Among the 310 herds, female herds were counted 150 times(48.4%), mixed herds 154 times(49.7%), and male herds 6 times(1.9%). Of 1 336 blue sheep classified by sex and age, adults, subadults and juveniles composed 64.1%,20.8%, and 15.1% respectively. The female:male ratio of adults was 1∶0.73. The ratio of adult females to juveniles was 1∶0.56, which is higher than the ratio recorded in spring (1∶0.43) or summer (1∶0.44).The results showed that the Helan Mountains State Nature Reserve has succeed in protecting blue sheep.
基金jointly supported by the National Key R&D Program of China(Grant No.2018YFC0603704)a Geological Survey Project of the China Geological Survey(DD20160050).
文摘Objective The Altyn Tagh marks the northern margin of the Qinghai-Tibet Plateau and lies between the Tarim block to the north and the Qaidam block,Qilian Orogen,and Kunlun orogenic belt to the south.The Altyn Tagh region contains ophiolite,high-to ultrahigh-pressure metamorphic rocks,and igneous rocks.Previous research has virified the occurrence of continental rifting,subduction,slab roll-back,and collision between the Tarim block and Proto-Tethys oceanic plate.Moreover,Kaladaban volcanic rocks are mainly distributed in the north Altyn region.Studies of the magmatic evolution of this region have proposed that Altyn oceanic plate was subducted during the Ordovician(Han et al.,2012;Wang et al.,2017).However,the specific timing and other aspects of the subduction are debated,and an investigation of granite porphyry in the Kaladaban area would improve our understanding of this subduction event.In this study,we present new U-Pb zircon dating result and Sr-Nd isotope composition data for granite porphyry from the North Altyn region.The objective is to constrain the timing of subduction of the North Altyn oceanic plate and establish the petrogenesis and magma source of the granite porphyry.
