Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits....Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry.展开更多
Mechanisms controlling phosphorus(P) availability and the roles of microorganisms in the efficient utilization of soil P in the wheat–maize double cropping system are poorly understood.In the present study,we conduct...Mechanisms controlling phosphorus(P) availability and the roles of microorganisms in the efficient utilization of soil P in the wheat–maize double cropping system are poorly understood.In the present study,we conducted a pot experiment for four consecutive wheat–maize seasons(2016–2018) using calcareous soils with high(30.36 mg kg^(–1)) and low(9.78 mg kg^(–1)) initial Olsen-P content to evaluate the effects of conventional P fertilizer application to both wheat and maize(Pwm) along with a reduced P fertilizer application only to wheat(Pw).The microbial community structure along with soil P availability parameters and crop yield were determined.The results showed that the Pw treatment reduces the annual P input by 33.3% without affecting the total yield for at least two consecutive years as compared with the Pwm treatment in the high Olsen-P soil.Soil water-soluble P concentrations in the Pw treatment were similar to those in the Pwm treatment at the 12-leaf collar stage when maize requires the most P.Furthermore,the soil P content significantly affected soil microbial communities,especially fungal communities.Meanwhile,the relative abundances of Proteobacteria and alkaline phosphatase(ALP) activity of Pw were significantly higher(by 11.4 and 13.3%) than those of Pwm in soil with high Olsen-P.The microfloral contribution to yield was greater than that of soil P content in soil with high Olsen-P.Relative abundances of Bacillus and Rhizobium were enriched in the Pw treatment compared with the Pwm treatment.Bacillus showed a significant positive correlation with acid phosphatase(ACP) activity,and Rhizobium displayed significant positive correlations with ACP and ALP in soil with high Olsen-P,which may enhance P availability.Our findings suggested that the application of P fertilization only to wheat is practical in high P soils to ensure optimal production in the wheat and maize double cropping system and that the soil P availability and microbial community may collaborate to maintain optimal yield in a wheat–maize double cropping system.展开更多
Four methyl aryl thioethers related to thiamphenicol syntheses and methyl phenyl sulfide were cleanly oxidized into methyl sulfones in high to excellent yields via catalytic green oxidation with aqueous hydrogen perox...Four methyl aryl thioethers related to thiamphenicol syntheses and methyl phenyl sulfide were cleanly oxidized into methyl sulfones in high to excellent yields via catalytic green oxidation with aqueous hydrogen peroxide in combination with sodium tungstate. When the same reactions were similarly performed in the absence of the catalyst, the corresponding sulfoxides could be obtained. This viable synthetic approach for the synthesis of DL-threo-thiamphenicol is a simple procedure, which has an economic advantage in view of its application for the large-scale synthesis because it can be carried out under mild conditions.展开更多
基金Project (No. 200442) supported by the Electronics DevelopmentFoundation for the Key Industrialization Project of the Ministry of0Information Industry, China
文摘Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry.
基金supported by the National Natural Science Foundation of China (41977019)the National Key Research and Development Program of China (2017YFD0200201 and 2017YFD0200706)+1 种基金the Shandong Key Research and Development Program, China (2019GNC106011)the Provincial Agricultural Science and Technology Park Construction Project, Shandong (LKZ2018143)。
文摘Mechanisms controlling phosphorus(P) availability and the roles of microorganisms in the efficient utilization of soil P in the wheat–maize double cropping system are poorly understood.In the present study,we conducted a pot experiment for four consecutive wheat–maize seasons(2016–2018) using calcareous soils with high(30.36 mg kg^(–1)) and low(9.78 mg kg^(–1)) initial Olsen-P content to evaluate the effects of conventional P fertilizer application to both wheat and maize(Pwm) along with a reduced P fertilizer application only to wheat(Pw).The microbial community structure along with soil P availability parameters and crop yield were determined.The results showed that the Pw treatment reduces the annual P input by 33.3% without affecting the total yield for at least two consecutive years as compared with the Pwm treatment in the high Olsen-P soil.Soil water-soluble P concentrations in the Pw treatment were similar to those in the Pwm treatment at the 12-leaf collar stage when maize requires the most P.Furthermore,the soil P content significantly affected soil microbial communities,especially fungal communities.Meanwhile,the relative abundances of Proteobacteria and alkaline phosphatase(ALP) activity of Pw were significantly higher(by 11.4 and 13.3%) than those of Pwm in soil with high Olsen-P.The microfloral contribution to yield was greater than that of soil P content in soil with high Olsen-P.Relative abundances of Bacillus and Rhizobium were enriched in the Pw treatment compared with the Pwm treatment.Bacillus showed a significant positive correlation with acid phosphatase(ACP) activity,and Rhizobium displayed significant positive correlations with ACP and ALP in soil with high Olsen-P,which may enhance P availability.Our findings suggested that the application of P fertilization only to wheat is practical in high P soils to ensure optimal production in the wheat and maize double cropping system and that the soil P availability and microbial community may collaborate to maintain optimal yield in a wheat–maize double cropping system.
文摘Four methyl aryl thioethers related to thiamphenicol syntheses and methyl phenyl sulfide were cleanly oxidized into methyl sulfones in high to excellent yields via catalytic green oxidation with aqueous hydrogen peroxide in combination with sodium tungstate. When the same reactions were similarly performed in the absence of the catalyst, the corresponding sulfoxides could be obtained. This viable synthetic approach for the synthesis of DL-threo-thiamphenicol is a simple procedure, which has an economic advantage in view of its application for the large-scale synthesis because it can be carried out under mild conditions.
