负载型Pd基催化剂是最有效的甲酸分解(FAD)制氢催化剂之一,其中氮化碳载体的N含量较高,但是通常一步热解法制备的氮化碳为块状,难以有效分散表面金属纳米粒子(NPs)。本文通过将尿素前驱体在溶剂化作用后热解得到功能化氮化碳,以此为载体...负载型Pd基催化剂是最有效的甲酸分解(FAD)制氢催化剂之一,其中氮化碳载体的N含量较高,但是通常一步热解法制备的氮化碳为块状,难以有效分散表面金属纳米粒子(NPs)。本文通过将尿素前驱体在溶剂化作用后热解得到功能化氮化碳,以此为载体,利用阴离子交换和硼氢化钠直接还原法制备了功能化氮化碳负载的Pd基催化剂(Pd/C 3 N 4-F)。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线光电子能谱(XPS)对材料结构进行表征,并通过气体质量流量计测试了催化剂的性能。Pd/C 3 N 4-F具有优异的催化FAD制氢性能,30℃下的初始TOF(总转换频率)值和质量比活性分别为1824 h-1和17.14 mol H 2/(g Pd·h)。对产物的气相色谱分析结果也表明没有副产物CO生成,表明催化剂具有优异的选择性。并且随着温度的升高(30~40℃),催化剂性能逐渐提高。展开更多
蜡样芽胞杆菌(Bacillus cereus, B. cereus)是一种兼性厌氧的革兰氏阳性杆菌,隶属于芽胞杆菌科蜡样芽胞杆菌属。该菌大量存在于土壤、饲料、水以及各种食品中。B. cereus常作为医药和动物生产中的益生菌使用,其还能对植物根部和土壤起...蜡样芽胞杆菌(Bacillus cereus, B. cereus)是一种兼性厌氧的革兰氏阳性杆菌,隶属于芽胞杆菌科蜡样芽胞杆菌属。该菌大量存在于土壤、饲料、水以及各种食品中。B. cereus常作为医药和动物生产中的益生菌使用,其还能对植物根部和土壤起固定作用[1]。B. cereus对于高温、紫外线及多种化学物质都有很强的抗性,具有较强的环境适应性[2]。展开更多
小反刍兽疫(Peste des petits ruminants,PPR)是由小反刍兽疫病毒(Peste des petits ruminants virus,PPRV)引起的一种高度接触性传染病,发病率和死亡率极高,给世界各国养殖业发展带来严峻的挑战。目前,疫苗接种是控制该病的关键策略,...小反刍兽疫(Peste des petits ruminants,PPR)是由小反刍兽疫病毒(Peste des petits ruminants virus,PPRV)引起的一种高度接触性传染病,发病率和死亡率极高,给世界各国养殖业发展带来严峻的挑战。目前,疫苗接种是控制该病的关键策略,随着生命科学研究的不断发展,基因工程苗的研究逐渐成熟,优点也不断显现出来。因此本文对PPR基因工程疫苗的最新研究进展进行了综述,以期为今后的科研提供新的视角和方向。展开更多
Security video communication is a challenging task,especially for wireless video applications.An efficient security multimedia system on embedded platform is designed.By analyzing the hardware architecture and resourc...Security video communication is a challenging task,especially for wireless video applications.An efficient security multimedia system on embedded platform is designed.By analyzing the hardware architecture and resource,the efficient DSP-based H.264/AVC coding is studied by efficient video coding techniques and system optimizing implementation.To protect the confidentiality and integrity of media information,a novel security mechanism is presented,which includes user identify authentication and a perceptual video encryption algorithm based on exploiting the special feature of entropy coding in H.264.Experimental results show that the proposed hardware framework has high performance and achieves a better balance between security and efficiency.The proposed security mechanism can achieve high security and low complexity cost,and has a little effect on the compression ratio and transmission bandwidth.What’s more,encoding and encryption at the same time,the performance of data process can meet real-time application.展开更多
To investigate the genetic composition of the carp （Cyprinus carpio） in Dongping Lake and to provide eytogenetie data for exploration, protection and appropriate utilization of the germplasm resources, karyotype of ...To investigate the genetic composition of the carp （Cyprinus carpio） in Dongping Lake and to provide eytogenetie data for exploration, protection and appropriate utilization of the germplasm resources, karyotype of the carp was analyzed in this study. In detail, colehieine was given to the fish an intraperitoneal route 24 h after the intraperitoneal injection of phytohemagglutinin （PHA） solution to arrest cells in metaphase. The kidney cells were collected for the preparation of chromosome specimens, which were observed under a microscope. Ten cells having correct number of chromosomes and clear morphology were photographed and zoomed to measure the relative length, arm ratio, ann number （NF） and other parameters of chromosomes. The results showed that the chromosome number of C. earpio in Dongping Lake was （2n = 100） ; the karyotype formula was （2n =20m ＋38sm ＋20st ＋22t）. The total number of chromosome arms （NF） was 158. By comparing the karyotype of Dongping Lake carp with that of other Cyprinus species, we concluded that Dongping Lake carp is more highly evolved among Cyprinus species.展开更多
文摘负载型Pd基催化剂是最有效的甲酸分解(FAD)制氢催化剂之一,其中氮化碳载体的N含量较高,但是通常一步热解法制备的氮化碳为块状,难以有效分散表面金属纳米粒子(NPs)。本文通过将尿素前驱体在溶剂化作用后热解得到功能化氮化碳,以此为载体,利用阴离子交换和硼氢化钠直接还原法制备了功能化氮化碳负载的Pd基催化剂(Pd/C 3 N 4-F)。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线光电子能谱(XPS)对材料结构进行表征,并通过气体质量流量计测试了催化剂的性能。Pd/C 3 N 4-F具有优异的催化FAD制氢性能,30℃下的初始TOF(总转换频率)值和质量比活性分别为1824 h-1和17.14 mol H 2/(g Pd·h)。对产物的气相色谱分析结果也表明没有副产物CO生成,表明催化剂具有优异的选择性。并且随着温度的升高(30~40℃),催化剂性能逐渐提高。
文摘小反刍兽疫(Peste des petits ruminants,PPR)是由小反刍兽疫病毒(Peste des petits ruminants virus,PPRV)引起的一种高度接触性传染病,发病率和死亡率极高,给世界各国养殖业发展带来严峻的挑战。目前,疫苗接种是控制该病的关键策略,随着生命科学研究的不断发展,基因工程苗的研究逐渐成熟,优点也不断显现出来。因此本文对PPR基因工程疫苗的最新研究进展进行了综述,以期为今后的科研提供新的视角和方向。
基金supported by the Project (No.2005CB321902) of Major State Basic Research Development (973)Project (No.yzdj0705) of Information Security Key Laboratory of the General Office of CPC Central Committee of China
文摘Security video communication is a challenging task,especially for wireless video applications.An efficient security multimedia system on embedded platform is designed.By analyzing the hardware architecture and resource,the efficient DSP-based H.264/AVC coding is studied by efficient video coding techniques and system optimizing implementation.To protect the confidentiality and integrity of media information,a novel security mechanism is presented,which includes user identify authentication and a perceptual video encryption algorithm based on exploiting the special feature of entropy coding in H.264.Experimental results show that the proposed hardware framework has high performance and achieves a better balance between security and efficiency.The proposed security mechanism can achieve high security and low complexity cost,and has a little effect on the compression ratio and transmission bandwidth.What’s more,encoding and encryption at the same time,the performance of data process can meet real-time application.
基金Supported by Agricultural Seed Development Project of Shandong ProvinceModern Agricultural Industrial Technology System Innovation Team of Shandong Province(SDAIT-14-011-03)
文摘To investigate the genetic composition of the carp （Cyprinus carpio） in Dongping Lake and to provide eytogenetie data for exploration, protection and appropriate utilization of the germplasm resources, karyotype of the carp was analyzed in this study. In detail, colehieine was given to the fish an intraperitoneal route 24 h after the intraperitoneal injection of phytohemagglutinin （PHA） solution to arrest cells in metaphase. The kidney cells were collected for the preparation of chromosome specimens, which were observed under a microscope. Ten cells having correct number of chromosomes and clear morphology were photographed and zoomed to measure the relative length, arm ratio, ann number （NF） and other parameters of chromosomes. The results showed that the chromosome number of C. earpio in Dongping Lake was （2n = 100） ; the karyotype formula was （2n =20m ＋38sm ＋20st ＋22t）. The total number of chromosome arms （NF） was 158. By comparing the karyotype of Dongping Lake carp with that of other Cyprinus species, we concluded that Dongping Lake carp is more highly evolved among Cyprinus species.
