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831.
为了优化生物破乳剂生产的发酵过程,提高生物破乳剂的产量,对破乳剂产生菌Bacillus mojavensis XH-1的分批发酵过程进行了研究.根据破乳剂产生菌XH-1发酵过程的特点,在Logistic方程和Luedeking-Piret方程的基础上,建立了菌株XH-1发酵过程中菌体生长、基质消耗和蛋白类破乳剂形成的动力学方程.采用Origin 7.5软件对试验数据进行处理,得到了破乳菌XH-1的分批发酵动力学模型参数.结果表明:模型预测值和试验值吻合较好,所建立的方程能较好地预测其实际发酵过程,具有很好的适用性,对生物破乳剂的发酵生产具有一定的指导意义. 相似文献
832.
833.
利用溶液悬浮法和微凝胶分散性好的特点,以Estane作为粘结剂,CL-20为主体炸药,制备了CL-20/Estane复合炸药,并对其进行SEM、XRD、DSC以及撞击感度性能测试。结果表明Estane可以成功包覆在CL-20表面,所得颗粒为类球形小微球,粒径在50mm 左右。包覆后晶型仍为ε型,包覆后样品与细化的CL-20相比热爆炸临界温度提升了1.52℃,活化能提高了7.19 kJ.mol-1,并且其撞击感度明显降低,特征落高(H50)由细化CL-20的20.79cm增加到30.64cm,H50数值提高了47%。 相似文献
834.
835.
The effect of laser doping of Al on the gas sensing behavior of nanocrystalline ZnO thin films is reported. The
doping of Al was carried out by the spin-coating of Al-precursors on nanocrystalline ZnO films followed by a
pulsed laser irradiation. The laser-doped films were characterized as a function of laser power density by
measuring the optical, structural, electrical, morphological and gas sensing properties of ZnO films. It was found
that the laser doping process resulted in an increase of electrical conductivity of ZnO films. The performance of
gas sensor was investigated for different concentrations of H2 and NH3 in the air. The results indicate that the
laser doping process can be utilized to improve the sensor characteristics such as sensitivity and response time
by optimization of laser power density. The optimum laser power is interpreted as the critical power level
required to compete the effective doping versus developing the effective grain boundaries. Also, the selectivity of
laser-doped ZnO sensors for H2 was studied for a likelihood practical gas mixture composed of H2, NH3 and
CH4. It is found that these films can be optimized to develop H2 and NH3 sensors in PPM level with a higher
selectivity over other reducing gases. 相似文献
836.
To enhance the microwave absorption performance of silicon carbide nanowires (SiCNWs), SiO2 nanoshells with a thickness of approximately 2 nm and Fe3O4 nanoparticles were grown on the surface of SiCNWs to form SiC@SiO2@Fe3O4 hybrids. The microwave absorption performance of the SiC@SiO2@Fe3O4 hybrids with different thicknesses was investigated in the frequency range from 2 to 18 GHz using a free-space antenna-based system. The results indicate that SiC@SiO2@Fe3O4 hybrids exhibit improved microwave absorption. In particular, in the case of an SiC@SiO2 to iron(III) acetylacetonate mass ratio of 1:3,themicrowave absorption with an absorber of 2-mm thickness exhibited a minimum reflection loss of?39.58 dB at 12.24 GHz. With respect to the enhanced microwave absorption mechanism, the Fe3O4 nanoparticles coated on SiC@SiO2 nanowires are proposed to balance the permeability and permittivity of the materials, contributing to the microwave attenuation. 相似文献
837.
Recycling of iron and steelmaking dusts is a key issue in environmental protection efforts and to ensure efficient utilization. In this investigation, we developed a novel recovery process that uses a dispersedin-situ phase induced by an explosive reaction of composite balls of iron and steelmaking dusts. We designed and prepared composite balls for this function using a laboratory model batch-type balling disc (at 12 r/min) and optimized the feeding modes in 180-t and 260-t basic oxygen furnace (BOF) converters. The results indicate that feeding composite balls into BOF converters is an effective novel technology for recovering iron and steelmaking dusts. The period after hot metal charging and prior to the oxygen-blowing process is the most reasonable time to feed composite balls. Composite ball treatment is not appro-priate for steel production with sulfur requirements lower than 80 ppm. The maximum composite ball feeding amount is 40 kg/t and the iron yield rate is better than 95%. Compared with the conventional recycling process of sludge and dust, this novel technology is more convenient and efficient, saving up to 309 RMB per ton of steel. Further investigation of this novel recycling technology is merited. 相似文献
838.
Novel concept of recycling sludge and dust to BOF converter through dispersed <Emphasis Type="Italic">in-situ</Emphasis> phase induced by composite ball explosive reaction
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Recycling of iron and steelmaking dusts is a key issue in environmental protection efforts and to ensure efficient utilization. In this investigation, we developed a novel recovery process that uses a dispersed in-situ phase induced by an explosive reaction of composite balls of iron and steelmaking dusts. We designed and prepared composite balls for this function using a laboratory model batch-type balling disc (at 12 r/min) and optimized the feeding modes in 180-t and 260-t basic oxygen furnace (BOF) converters. The results indicate that feeding composite balls into BOF converters is an effective novel technology for recovering iron and steelmaking dusts. The period after hot metal charging and prior to the oxygen-blowing process is the most reasonable time to feed composite balls. Composite ball treatment is not appropriate for steel production with sulfur requirements lower than 80 ppm. The maximum composite ball feeding amount is 40 kg/t and the iron yield rate is better than 95%. Compared with the conventional recycling process of sludge and dust, this novel technology is more convenient and efficient, saving up to 309 RMB per ton of steel. Further investigation of this novel recycling technology is merited. 相似文献
839.
研究了一类具p(x)-拉普拉斯和阻尼项的黏弹性双曲方程解的性质,利用Faedo-Galerki方法和嵌入理论,借助标准的常微分方程求解方法,给出了初边值问题弱解的存在性结果. 相似文献
840.
通过收集廊坊城区水文地质条件、地面沉降监测等资料,分析地下水漏斗变化和地面沉降发展情况,研究廊坊城区地面沉降与地下水漏斗响应关系。首先,深层地下水是廊坊城区的主要水源,2001—2015年供水量呈整体上升趋势,其中生产用水和家庭用水占主要部分,长期开采深层地下水形成地下水漏斗,漏斗断面呈"V"字形。其次,基于合成孔径雷达干涉(interferometric synthetic aperture radar,InSAR)技术,廊坊市城区大部沉降速率60 mm/a,局部达80 mm/a。再者,地下水漏斗变化和地面沉降响应关系显示,地下水漏斗与地面沉降中心基本吻合,地下水位开采量增加,造成深层水位下降,导致地面沉降速率不断变大,影响范围亦增大,地下水位下降成为该区地面层沉降主要影响因素,同时建筑群荷载增加对地面沉降亦产生不利影响。因此,开展地面沉降与地下水漏斗响应关系研究可为地面沉降灾害防治提供理论依据。 相似文献