The present study is an attempt to find a solution central authoritarian forest services in Sinnar State, Sudan for the forest management conflicts existing between local people and the Sinnar was purposely selected a...The present study is an attempt to find a solution central authoritarian forest services in Sinnar State, Sudan for the forest management conflicts existing between local people and the Sinnar was purposely selected as a study area because 9% (496.4×103 ha) of the forest reserve area of the entire country is located in this state. A comprehensive survey consisting of field observations, questionnaires and interviews was carried out specifically in the Alsabonabi area for its heterogeneous local community. The results show that the existing management system of the sunt forest reserve (the Alumbwa forest) has failed to support the local people, both residents and semi-nomads. Hence, the present study proposes a series of strategic and organizational changes in order to help in showing the way for integrated and participatory forest resource management and improving the welfare of all impoverished rural communities.展开更多
The “Huang gua” melons were measured for their physical properties including firmness and static elastic modulus. The vibrational characteristics of fruits and vegetables are governed by their elastic modulus (firmn...The “Huang gua” melons were measured for their physical properties including firmness and static elastic modulus. The vibrational characteristics of fruits and vegetables are governed by their elastic modulus (firmness), mass, and geometry. Therefore, it is possible to evaluate firmness of fruits and vegetables based on their vibrational characteristics. Analysis of the vibration responses of a fruit is suggested for measuring elastic properties (Firmness) non-destructively. The impulse response method is often used to measure firmness of fruits. The fruit was excited using three types of balls (wooden, steel and rubber) and the vibration is detected by an accelerometer. The Instron device was used to measure the static elastic modulus of the inner, middle and outer portions of melon flesh. Finite element (FE) technique was used to determine the optimum excitation location of the chosen measurement sensor and to analyze the mode shape fruits. Four types of mode shapes (torsional or flexural mode shape, first-type, second-type spherical mode and breathing mode shape) were found. Finite element simulation results agreed well with experimental results. Correlation between the firmness and resonant frequency (r2=0.91) and between the resonant frequency and stiffness factor (r2=0.74) existed. The optimum location and suitable direction for excitation and response measurement on the fruit were suggested.展开更多
The weak-type (1, 1) boundedness of the higher order Riesz-Laguerre transforms associated with the Laguerre polynomials and the boundedness for the Riesz-Laguerre transforms of order 2 are considered. We discuss a pol...The weak-type (1, 1) boundedness of the higher order Riesz-Laguerre transforms associated with the Laguerre polynomials and the boundedness for the Riesz-Laguerre transforms of order 2 are considered. We discuss a polynomial weight w that makes the Riesz-Laguerre transforms of order greater than or equal to 2 continuous from L<sup>1</sup> (wdμ<sub>α</sub>) into L<sup>1,∞</sup> (dμ<sub>α</sub>), under specific value α, where μα</sub> is the Laguerre measure.展开更多
The nutritive value of rangelands in Southern Darfur, Sudan could be improved by introduction and multiplication of nutritious forbs with the objective of increasing livestock production in the area. The present study...The nutritive value of rangelands in Southern Darfur, Sudan could be improved by introduction and multiplication of nutritious forbs with the objective of increasing livestock production in the area. The present study was conducted to evaluate the nutritive value and palatability of eleven range forbs collected at flowering stage from Gahzal Gawazat, Southern Darfur, Sudan using chemical analysis. The crude protein (CP) ranged from 6.8% in Oxygonum atriplicifolium with lowest digestible crude protein (DCP) 2.8% to 16.4% in Zornia diphylla with highest DCP 11.73%. The highest and the lowest crude fiber (CF) values were obtained in Commelina spp (56.4%) and Sesamum alatum (25.9%), respectively. NDF and DMI values were maximum and minimum for Zornia diphylla (44.9 and 2.67%) and Alysicarpus glumaceus (35.3 and 3.4%), respectively. The total digestible nutrients (TDN) ranged from 57.1% in Blepharis linariifolia to 69.3% in Tribulus terrestris with highest digestible energy (DE) in later while the lowest DE was obtained in Commelina spp (2.4%). The calculated in vitro organic matter digestibility (IVOMD) was highest for the Canavalia ensiformis (50.27%) and lowest value (43.17%) for Commelina spp. Zornia diphylla, Tribulus terrestris and Sesamum alatum showed highest nutritive value, while Alysicarpus glumaceus, Oldenlandia senegalensis and Chrozophora brocchiana showed highest palatability. It is concluded that these rangeland forbs are palatable and their CP and energy contents are sufficient to support different classes of livestock in South Darfur, Sudan.展开更多
Since the pesticides are considered as an essential component for crops production through controlling pests, they have shown a negative effect on crops and soil environment when used intensively. This experiment was ...Since the pesticides are considered as an essential component for crops production through controlling pests, they have shown a negative effect on crops and soil environment when used intensively. This experiment was conducted at Wadi Soba farm (Sharq Elneel) Khartoum, Sudan. It aimed to study the effect of Sevin residuals on carrot growth and Azotobacter spp. colonies growth. Carrot planted in late February 2013, Sevin pesticide (2.5 L/ha and 5 L/ha) was added to estimate plant height, dry weight, the number of plant leaves and the number of Azotobacter spp. colonies isolated from the carrot rhizosphere (0 - 15 cm). The obtained results showed that the Sevin recommended dose (2.5 L/ha) relatively had a positive effect on the plant height, dry weight, and the number of plant leaves. The average of plant height for recommended dose was 59.67 cm compared to control (53.67 cm) and high dose (27.33 cm). The average of plant dry weight obtained by the recommended dose was 503.33 g and for control was 476.67 g and for high dose was 166.7 g, it decreased 67% from control and recommended dose. The average of plant leaves number were 25.34, 13.66 and 21.33 for recommended dose, high dose and control respectively, the number of leaves increased about 16% by recommended dose and decreased 35% by high dose. The average of Azotobacter spp. colonies obtained by high dose of Sevin demonstrated a lower numbers which were 20 × 104, 5.67 × 106 and 0.33 × 108 compared with control (78.33 × 104, 44 × 106 and 15.33 × 108) and the recommended dose (64 × 104, 33 × 106 and 7 × 108). The high dose of Sevin had a negative effect on both carrot growth and Azotobacter spp. colonies growth.展开更多
基金supported by the National Key Technology R&D Program of China during the 12th Five-Year Plan Period(No.2012BAD16B02)
文摘The present study is an attempt to find a solution central authoritarian forest services in Sinnar State, Sudan for the forest management conflicts existing between local people and the Sinnar was purposely selected as a study area because 9% (496.4×103 ha) of the forest reserve area of the entire country is located in this state. A comprehensive survey consisting of field observations, questionnaires and interviews was carried out specifically in the Alsabonabi area for its heterogeneous local community. The results show that the existing management system of the sunt forest reserve (the Alumbwa forest) has failed to support the local people, both residents and semi-nomads. Hence, the present study proposes a series of strategic and organizational changes in order to help in showing the way for integrated and participatory forest resource management and improving the welfare of all impoverished rural communities.
基金Project supported by the National Natural Science Foundation of China (No. 30370371) and the Natural Science Foundation of Zheji-ang Province (No. 301267), China
文摘The “Huang gua” melons were measured for their physical properties including firmness and static elastic modulus. The vibrational characteristics of fruits and vegetables are governed by their elastic modulus (firmness), mass, and geometry. Therefore, it is possible to evaluate firmness of fruits and vegetables based on their vibrational characteristics. Analysis of the vibration responses of a fruit is suggested for measuring elastic properties (Firmness) non-destructively. The impulse response method is often used to measure firmness of fruits. The fruit was excited using three types of balls (wooden, steel and rubber) and the vibration is detected by an accelerometer. The Instron device was used to measure the static elastic modulus of the inner, middle and outer portions of melon flesh. Finite element (FE) technique was used to determine the optimum excitation location of the chosen measurement sensor and to analyze the mode shape fruits. Four types of mode shapes (torsional or flexural mode shape, first-type, second-type spherical mode and breathing mode shape) were found. Finite element simulation results agreed well with experimental results. Correlation between the firmness and resonant frequency (r2=0.91) and between the resonant frequency and stiffness factor (r2=0.74) existed. The optimum location and suitable direction for excitation and response measurement on the fruit were suggested.
文摘The weak-type (1, 1) boundedness of the higher order Riesz-Laguerre transforms associated with the Laguerre polynomials and the boundedness for the Riesz-Laguerre transforms of order 2 are considered. We discuss a polynomial weight w that makes the Riesz-Laguerre transforms of order greater than or equal to 2 continuous from L<sup>1</sup> (wdμ<sub>α</sub>) into L<sup>1,∞</sup> (dμ<sub>α</sub>), under specific value α, where μα</sub> is the Laguerre measure.
文摘The nutritive value of rangelands in Southern Darfur, Sudan could be improved by introduction and multiplication of nutritious forbs with the objective of increasing livestock production in the area. The present study was conducted to evaluate the nutritive value and palatability of eleven range forbs collected at flowering stage from Gahzal Gawazat, Southern Darfur, Sudan using chemical analysis. The crude protein (CP) ranged from 6.8% in Oxygonum atriplicifolium with lowest digestible crude protein (DCP) 2.8% to 16.4% in Zornia diphylla with highest DCP 11.73%. The highest and the lowest crude fiber (CF) values were obtained in Commelina spp (56.4%) and Sesamum alatum (25.9%), respectively. NDF and DMI values were maximum and minimum for Zornia diphylla (44.9 and 2.67%) and Alysicarpus glumaceus (35.3 and 3.4%), respectively. The total digestible nutrients (TDN) ranged from 57.1% in Blepharis linariifolia to 69.3% in Tribulus terrestris with highest digestible energy (DE) in later while the lowest DE was obtained in Commelina spp (2.4%). The calculated in vitro organic matter digestibility (IVOMD) was highest for the Canavalia ensiformis (50.27%) and lowest value (43.17%) for Commelina spp. Zornia diphylla, Tribulus terrestris and Sesamum alatum showed highest nutritive value, while Alysicarpus glumaceus, Oldenlandia senegalensis and Chrozophora brocchiana showed highest palatability. It is concluded that these rangeland forbs are palatable and their CP and energy contents are sufficient to support different classes of livestock in South Darfur, Sudan.
文摘Since the pesticides are considered as an essential component for crops production through controlling pests, they have shown a negative effect on crops and soil environment when used intensively. This experiment was conducted at Wadi Soba farm (Sharq Elneel) Khartoum, Sudan. It aimed to study the effect of Sevin residuals on carrot growth and Azotobacter spp. colonies growth. Carrot planted in late February 2013, Sevin pesticide (2.5 L/ha and 5 L/ha) was added to estimate plant height, dry weight, the number of plant leaves and the number of Azotobacter spp. colonies isolated from the carrot rhizosphere (0 - 15 cm). The obtained results showed that the Sevin recommended dose (2.5 L/ha) relatively had a positive effect on the plant height, dry weight, and the number of plant leaves. The average of plant height for recommended dose was 59.67 cm compared to control (53.67 cm) and high dose (27.33 cm). The average of plant dry weight obtained by the recommended dose was 503.33 g and for control was 476.67 g and for high dose was 166.7 g, it decreased 67% from control and recommended dose. The average of plant leaves number were 25.34, 13.66 and 21.33 for recommended dose, high dose and control respectively, the number of leaves increased about 16% by recommended dose and decreased 35% by high dose. The average of Azotobacter spp. colonies obtained by high dose of Sevin demonstrated a lower numbers which were 20 × 104, 5.67 × 106 and 0.33 × 108 compared with control (78.33 × 104, 44 × 106 and 15.33 × 108) and the recommended dose (64 × 104, 33 × 106 and 7 × 108). The high dose of Sevin had a negative effect on both carrot growth and Azotobacter spp. colonies growth.