The surface injection and production system(SIPS)is a critical component for effective injection and production processes in underground natural gas storage.As a vital channel,the rational design of the surface inject...The surface injection and production system(SIPS)is a critical component for effective injection and production processes in underground natural gas storage.As a vital channel,the rational design of the surface injection and production(SIP)pipeline significantly impacts efficiency.This paper focuses on the SIP pipeline and aims to minimize the investment costs of surface projects.An optimization model under harmonized injection and production conditions was constructed to transform the optimization problem of the SIP pipeline design parameters into a detailed analysis of the injection condition model and the production condition model.This paper proposes a hybrid genetic algorithm generalized reduced gradient(HGA-GRG)method,and compares it with the traditional genetic algorithm(GA)in a practical case study.The HGA-GRG demonstrated significant advantages in optimization outcomes,reducing the initial cost by 345.371×10^(4) CNY compared to the GA,validating the effectiveness of the model.By adjusting algorithm parameters,the optimal iterative results of the HGA-GRG were obtained,providing new research insights for the optimal design of a SIPS.展开更多
Sweet potatoes are significant cash crops,however,their yield and quality are greatly compromised by viral diseases.In this study,the complete genomic sequences of two Sweet Potato Virus 2(SPV2)isolates from infected ...Sweet potatoes are significant cash crops,however,their yield and quality are greatly compromised by viral diseases.In this study,the complete genomic sequences of two Sweet Potato Virus 2(SPV2)isolates from infected sweet potato leaves in the Shandong(designated as SPV2-SDYT,GenBank No.PQ855660.1)and Jiangsu(designated as SPV2-JSXZ,GenBank No.PQ855661.1)provinces in China were obtained using 5′RACE and RT-PCR amplification.Consistency,phylogeny,codon usage bias,recombination,and selection pressure analyses were conducted using the SPV2-SDYT and SPV2-JSXZ genome sequences.The complete genome sequences of SPV2-SDYT and SPV2-JSXZ were 10561 nucleotides(nt)in length,with respective nucleotide and amino acid identities of 99.25%and 99.12%,respectively.Both isolates were closely related to the SPV2 isolate from China(SPV2-LN).In both SPV2-SDYT and SPV2-JSXZ,the identity of the P1 protein was the highest,whereas that of the P3 protein was the lowest.There were 26 codons with relatively synonymous codon usage(RSCU)values greater than 1 in SPV2-SDYT and 27 codons with RSCU values greater than 1 in SPV2-JSXZ.High-frequency codons in their genomes were predominantly found to end with A/U.Recombination analysis revealed no major recombination sites in either SPV2-SDYT or SPV2-JSXZ.Further selection pressure analysis showed that the non-synonymous substitution rate/synonymous substitution rate(dN/dS)value of all 10 SPV2 proteins was less than 1.This is the first report on the evolutionary relationships of the 17 known SPV2 isolates.Our findings lay the molecular groundwork for preventing and controlling SPV2 infection in root-tuber crops.These findings also contribute to our understanding of the spread and evolution of SPV2,its pathogenic mechanisms,and the development of antiviral strategies against it.展开更多
According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since t...According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since the period of instrumental observation began, being only slightly lower than the values recorded in 2016 and 2020, and historically record-breaking GMST emerged from May to July 2023. Further analysis also indicates that if the surface temperature in the last five months of 2023 approaches the average level of the past five years, the annual average surface temperature anomaly in 2023 of approximately 1.26°C will break the previous highest surface temperature, which was recorded in 2016of approximately 1.25°C(both values relative to the global pre-industrialization period, i.e., the average value from 1850 to1900). With El Ni?o triggering a record-breaking hottest July, record-breaking average annual temperatures will most likely become a reality in 2023.展开更多
Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibili...Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibility in Malus plants.In this experiment,88 Malus germplasm resources,such as Aihuahong,Xishuhaitang,and Reguanzi,were used as materials.Seven gene-specific primer combinations were used in the genotype identification.PCR amplification using leaf DNA produced a single S-RNase gene fragment in all materials.The results revealed that 70 of the identified materials obtained a complete S-RNase genotype,while only one S-RNase gene was found in 18 of them.Through homology comparison and analysis,13 S-RNase genotypes were obtained:S_(1)S_(2)(Aihuahong,etc.),S_(1)S_(28)(Xixian Haitang,etc.),S_(1)S_(51)(Hebei Pingdinghaitang),S_(1)S_(3)(Xiangyangcun Daguo,etc.),S_(2)S_(3)(Zhaiyehaitang,etc.),S_(3)S_(51)(Xishan 1),S_(3)S_(28)(Huangselihaerde,etc.),S_(2)S_(28)(Honghaitang,etc.),S_(4)S_(28)(Bo 11),S_(7)S_(28)(Jiuquan Shaguo),S_(10)S_e(Dongchengguan 13),S_(10)S_(21)(Dongxiangjiao)and S_(3)S_(51)(Xiongyue Haitang).Simultaneously,the frequency of the S gene in the tested materials was analyzed.The findings revealed that different S genes had varying frequencies in Malus resources,as well as varying frequencies between intraspecific and interspecific.S_(3) had the highest frequency of 68.18%,followed by S_(1)(42.04%).In addition,the phylogenetic tree and origin evolution analysis revealed that the S gene differentiation was completed prior to the formation of various apple species,that cultivated species also evolved new S genes,and that the S_(50) gene is the oldest S allele in Malus plants.The S_(1),S_(29),and S_(33) genes in apple-cultivated species,on the other hand,may have originated in M.sieversii,M.hupehensis,and M.kansuensis,respectively.In addition to M.sieversii,M.kansuensis and M.sikkimensis may have also played a role in the origin and evolution of some Chinese apples.展开更多
In 2022,a sharp rise in global cases of mpox virus(MPXV)led the World Health Organization(WHO)to declare it a public health emergency of international concern.However,progress in developing drugs targeting MPXV has be...In 2022,a sharp rise in global cases of mpox virus(MPXV)led the World Health Organization(WHO)to declare it a public health emergency of international concern.However,progress in developing drugs targeting MPXV has been slow.Here,we investigate the natural alkaloid narciclasine as a potential inhibitor of poxviruses.Our investigation demonstrates that narciclasine at 40 nmol/L(nM)to 160 nM dosages effectively blocks vaccinia virus(VACV),a representative poxvirus.Specifically,narciclasine disrupts the production of extracellular enveloped virus(EEV),which is crucial for viral spread.Narciclasine’s antiviral impact is probably attributed to its activation of the RhoA signaling pathway.This study highlights narciclasine’s potential as a promising new therapeutic candidate against poxviruses,offering prospects for its development into a potent antiviral agent that is essential for combating emerging poxvirus outbreaks.展开更多
Type 1 regulatory T cells(CD4^(+)Foxp3^(−)LAG3^(+)CD49b^(+)),or Tr1 cells,have a remarkable capacity to suppress autoimmune inflamma tion through IL-10.1 Although the signals that lead to Tr1-cell differentiation are ...Type 1 regulatory T cells(CD4^(+)Foxp3^(−)LAG3^(+)CD49b^(+)),or Tr1 cells,have a remarkable capacity to suppress autoimmune inflamma tion through IL-10.1 Although the signals that lead to Tr1-cell differentiation are not completely elucidated,it is known that IL 27 plays a major role in this phenomenon.展开更多
The escalating challenges in water treatment,exacerbated by climate change,have catalyzed the emergence of innovative solutions.Novel adsorption separation and membrane filtration methodologies,achieved through molecu...The escalating challenges in water treatment,exacerbated by climate change,have catalyzed the emergence of innovative solutions.Novel adsorption separation and membrane filtration methodologies,achieved through molecular structure manipulation,are gaining traction in the environmental and energy sectors.Separation technologies,integral to both the chemical industry and everyday life,encompass concentration and purification processes.Macrocycles,recognized as porous materials,have been prevalent in water treatment due to their inherent benefits:stability,adaptability,and facile modification.These structures typically exhibit high selectivity and reversibility for specific ions or molecules,enhancing their efficacy in water purification processes.The progression of purification methods utilizing macrocyclic frameworks holds promise for improved adsorption separations,membrane filtrations,resource utilization,and broader water treatment applications.This review encapsulates the latest breakthroughs in macrocyclic host-vip chemistry,with a focus on adsorptive and membrane separations.The aim is to spotlight strategies for optimizing macrocycle designs and their subsequent implementation in environmental and energy endeavors,including desalination,elemental extraction,seawater energy harnessing,and sustainable extraction.Hopefully,this review can guide the design and functionality of macrocycles,offering a significantly promising pathway for pollutant removal and resource utilization.展开更多
Several public-key encryption schemes used to solve the problem of ciphertext data processing on the fly are discussed. A new targeted fully homomorphic encryption scheme based on the discrete logarithm problem is pre...Several public-key encryption schemes used to solve the problem of ciphertext data processing on the fly are discussed. A new targeted fully homomorphic encryption scheme based on the discrete logarithm problem is presented. Public-key encryption cryptosystems are classified to examine homomorphic encryption. Without employing techniques proposed by Gentry such as somewhat homomorphic and bootstrapping techniques, or relinearization technique proposed by Brakerski et al., a new method called "Double Decryption Algorithm" is employed in our cryptography to satisfy a fully or targeted fully homomorphic property. Inspired by EIGamal and BGN cryptography, we obtain the desired fully homomorphic property by selecting a new group and adding an extra component to the ciphertext. Proof of semantic security is also demonstrated.展开更多
Bismaleimides bearing 2,5-diphenyl-l,3,4- oxadiazole chromophores at para, meta, ortho position and corresponding saturated bissuccinimides were synthe- sized. Several synthetic strategies for these bismaleimides were...Bismaleimides bearing 2,5-diphenyl-l,3,4- oxadiazole chromophores at para, meta, ortho position and corresponding saturated bissuccinimides were synthe- sized. Several synthetic strategies for these bismaleimides were discussed in detail. Almost no or very weak fluorescence was observed for these bismaleimides, however, the bissuccinimides show a strong fluorescence. The effect of molecular geometry on optical behavior and fluorescence quenching mechanism were investigated by UV-vis absorption and fluorescence emission spectro- scopy. The electron coupling of ground state of p- bismaleimide is stronger than those of m- and o- bismaleimides.p-Bissuccinimide displays increasing fluor- escence quantum yields with red shifts of 22-24 nm, compared to m-bissuccinimide. Polymerizable C=C bonds play a key role in the intramolecular fluorescence quenching.展开更多
The cloud’s storage and query of private information have the cryptographic scholar due to the proliferation of cloud computing.In the traditional query mode,the private information stored in the cloud is at risk of ...The cloud’s storage and query of private information have the cryptographic scholar due to the proliferation of cloud computing.In the traditional query mode,the private information stored in the cloud is at risk of being leaked.In order to solve this problem,a cloud ciphertext database system based on homomorphic encryption is a valid workaround.This paper presents a new cloud ciphertext database system model,which is based on the existing ciphertext database mode research and homomorphic properties.This paper also implements a ciphertext database system based on a CRT-based additive homomorphic scheme according to the model.Through theoretical analysis,the model is CPA-level safe and correct.The experimental results show that users can correctly query and download the data in the ciphertext database on the untrusted cloud server through the model,and it has efficiency advantages.展开更多
In this paper we have studied adsorption and surface reactions of acetylene and ethylene on Co(0001)in detail by temperature desorption spectrum(TDS),X-ray photoelectron spectroscopy(XPS)and ultraviolet photoelectron ...In this paper we have studied adsorption and surface reactions of acetylene and ethylene on Co(0001)in detail by temperature desorption spectrum(TDS),X-ray photoelectron spectroscopy(XPS)and ultraviolet photoelectron spectroscopy(UPS).C_(2)H_(4) adsorption at 130 and 300 K followed by subsequent heating mainly forms C_(2) clusters and graphitic carbon,respectively,while C_(2)H_(4) decomposes at 400 and 500 K to form dominant graphitic carbon and carbon adatoms,respectively.C_(2)H_(2) molecularly adsorbs at 130 K but exclusively dehydrogenates upon heating.The resulting C_(2)H_(2)(a)species at low coverages remains stable up to 400 K and then exclusively dehydrogenates into C_(2) clusters,while the resulting C_(2)H_(2)(a)species at high coverages remains stable up to 310 K and then majorly dehydrocyclizates into(C_(2)H)n intermediates with ring structures at 340 K which further dehydrogenates into graphitic carbon,and minorly dehydrogenates into C_(2) clusters.Exposed at 370 K,C_(2)H_(2) dehydrocyclizates into(C_(2)H)n intermediates with ring structures.These temperature and coverage dependent surface reactions of C_(2)H_(2) and C_(2)H_(4) on Co(0001)greatly enrich our fundamental understanding of Co-catalyzed F-T synthesis reaction.展开更多
基金the National Natural Science Foundation of China,grant numbers 51704253 and 52474084.
文摘The surface injection and production system(SIPS)is a critical component for effective injection and production processes in underground natural gas storage.As a vital channel,the rational design of the surface injection and production(SIP)pipeline significantly impacts efficiency.This paper focuses on the SIP pipeline and aims to minimize the investment costs of surface projects.An optimization model under harmonized injection and production conditions was constructed to transform the optimization problem of the SIP pipeline design parameters into a detailed analysis of the injection condition model and the production condition model.This paper proposes a hybrid genetic algorithm generalized reduced gradient(HGA-GRG)method,and compares it with the traditional genetic algorithm(GA)in a practical case study.The HGA-GRG demonstrated significant advantages in optimization outcomes,reducing the initial cost by 345.371×10^(4) CNY compared to the GA,validating the effectiveness of the model.By adjusting algorithm parameters,the optimal iterative results of the HGA-GRG were obtained,providing new research insights for the optimal design of a SIPS.
基金Funding Statement:This work was funded by the National Natural Science Foundation of China(32100132)Shandong Province Natural Sciences Foundation of China(ZR2021QC008)+1 种基金Youth Innovation Team Program'in College of Shandong Province of China(2022KJ119)supported by Young Talent of Lifting Engineering for Science and Technology in Shandong,China(SDAST2024QT085).
文摘Sweet potatoes are significant cash crops,however,their yield and quality are greatly compromised by viral diseases.In this study,the complete genomic sequences of two Sweet Potato Virus 2(SPV2)isolates from infected sweet potato leaves in the Shandong(designated as SPV2-SDYT,GenBank No.PQ855660.1)and Jiangsu(designated as SPV2-JSXZ,GenBank No.PQ855661.1)provinces in China were obtained using 5′RACE and RT-PCR amplification.Consistency,phylogeny,codon usage bias,recombination,and selection pressure analyses were conducted using the SPV2-SDYT and SPV2-JSXZ genome sequences.The complete genome sequences of SPV2-SDYT and SPV2-JSXZ were 10561 nucleotides(nt)in length,with respective nucleotide and amino acid identities of 99.25%and 99.12%,respectively.Both isolates were closely related to the SPV2 isolate from China(SPV2-LN).In both SPV2-SDYT and SPV2-JSXZ,the identity of the P1 protein was the highest,whereas that of the P3 protein was the lowest.There were 26 codons with relatively synonymous codon usage(RSCU)values greater than 1 in SPV2-SDYT and 27 codons with RSCU values greater than 1 in SPV2-JSXZ.High-frequency codons in their genomes were predominantly found to end with A/U.Recombination analysis revealed no major recombination sites in either SPV2-SDYT or SPV2-JSXZ.Further selection pressure analysis showed that the non-synonymous substitution rate/synonymous substitution rate(dN/dS)value of all 10 SPV2 proteins was less than 1.This is the first report on the evolutionary relationships of the 17 known SPV2 isolates.Our findings lay the molecular groundwork for preventing and controlling SPV2 infection in root-tuber crops.These findings also contribute to our understanding of the spread and evolution of SPV2,its pathogenic mechanisms,and the development of antiviral strategies against it.
基金support from the National Natural Science Foundation of China (Grant Nos. 41975105 and 42375022)。
文摘According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since the period of instrumental observation began, being only slightly lower than the values recorded in 2016 and 2020, and historically record-breaking GMST emerged from May to July 2023. Further analysis also indicates that if the surface temperature in the last five months of 2023 approaches the average level of the past five years, the annual average surface temperature anomaly in 2023 of approximately 1.26°C will break the previous highest surface temperature, which was recorded in 2016of approximately 1.25°C(both values relative to the global pre-industrialization period, i.e., the average value from 1850 to1900). With El Ni?o triggering a record-breaking hottest July, record-breaking average annual temperatures will most likely become a reality in 2023.
基金financially supported by the Agricultural Science and Technology Innovation Program(CAASASTIP-2021-RIP-02)。
文摘Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibility in Malus plants.In this experiment,88 Malus germplasm resources,such as Aihuahong,Xishuhaitang,and Reguanzi,were used as materials.Seven gene-specific primer combinations were used in the genotype identification.PCR amplification using leaf DNA produced a single S-RNase gene fragment in all materials.The results revealed that 70 of the identified materials obtained a complete S-RNase genotype,while only one S-RNase gene was found in 18 of them.Through homology comparison and analysis,13 S-RNase genotypes were obtained:S_(1)S_(2)(Aihuahong,etc.),S_(1)S_(28)(Xixian Haitang,etc.),S_(1)S_(51)(Hebei Pingdinghaitang),S_(1)S_(3)(Xiangyangcun Daguo,etc.),S_(2)S_(3)(Zhaiyehaitang,etc.),S_(3)S_(51)(Xishan 1),S_(3)S_(28)(Huangselihaerde,etc.),S_(2)S_(28)(Honghaitang,etc.),S_(4)S_(28)(Bo 11),S_(7)S_(28)(Jiuquan Shaguo),S_(10)S_e(Dongchengguan 13),S_(10)S_(21)(Dongxiangjiao)and S_(3)S_(51)(Xiongyue Haitang).Simultaneously,the frequency of the S gene in the tested materials was analyzed.The findings revealed that different S genes had varying frequencies in Malus resources,as well as varying frequencies between intraspecific and interspecific.S_(3) had the highest frequency of 68.18%,followed by S_(1)(42.04%).In addition,the phylogenetic tree and origin evolution analysis revealed that the S gene differentiation was completed prior to the formation of various apple species,that cultivated species also evolved new S genes,and that the S_(50) gene is the oldest S allele in Malus plants.The S_(1),S_(29),and S_(33) genes in apple-cultivated species,on the other hand,may have originated in M.sieversii,M.hupehensis,and M.kansuensis,respectively.In addition to M.sieversii,M.kansuensis and M.sikkimensis may have also played a role in the origin and evolution of some Chinese apples.
基金supported by the National Natural Science Foundation of China(82272306 and 82072270)Shandong Provincial Natural Science Foundation(ZR2024MH017)Taishan Scholars Program(tstp20221142).
文摘In 2022,a sharp rise in global cases of mpox virus(MPXV)led the World Health Organization(WHO)to declare it a public health emergency of international concern.However,progress in developing drugs targeting MPXV has been slow.Here,we investigate the natural alkaloid narciclasine as a potential inhibitor of poxviruses.Our investigation demonstrates that narciclasine at 40 nmol/L(nM)to 160 nM dosages effectively blocks vaccinia virus(VACV),a representative poxvirus.Specifically,narciclasine disrupts the production of extracellular enveloped virus(EEV),which is crucial for viral spread.Narciclasine’s antiviral impact is probably attributed to its activation of the RhoA signaling pathway.This study highlights narciclasine’s potential as a promising new therapeutic candidate against poxviruses,offering prospects for its development into a potent antiviral agent that is essential for combating emerging poxvirus outbreaks.
文摘Type 1 regulatory T cells(CD4^(+)Foxp3^(−)LAG3^(+)CD49b^(+)),or Tr1 cells,have a remarkable capacity to suppress autoimmune inflamma tion through IL-10.1 Although the signals that lead to Tr1-cell differentiation are not completely elucidated,it is known that IL 27 plays a major role in this phenomenon.
基金supported by the National Key Research&Development Program(2022YFE0199800)National Natural Science Foundation of China(82104065,32061143045)+1 种基金Distinguished Young Research Project of Anhui Higher Education Institution(2022AH020035)Science and Technology Plans of Tianjin(22ZYJDSS00070).
文摘The escalating challenges in water treatment,exacerbated by climate change,have catalyzed the emergence of innovative solutions.Novel adsorption separation and membrane filtration methodologies,achieved through molecular structure manipulation,are gaining traction in the environmental and energy sectors.Separation technologies,integral to both the chemical industry and everyday life,encompass concentration and purification processes.Macrocycles,recognized as porous materials,have been prevalent in water treatment due to their inherent benefits:stability,adaptability,and facile modification.These structures typically exhibit high selectivity and reversibility for specific ions or molecules,enhancing their efficacy in water purification processes.The progression of purification methods utilizing macrocyclic frameworks holds promise for improved adsorption separations,membrane filtrations,resource utilization,and broader water treatment applications.This review encapsulates the latest breakthroughs in macrocyclic host-vip chemistry,with a focus on adsorptive and membrane separations.The aim is to spotlight strategies for optimizing macrocycle designs and their subsequent implementation in environmental and energy endeavors,including desalination,elemental extraction,seawater energy harnessing,and sustainable extraction.Hopefully,this review can guide the design and functionality of macrocycles,offering a significantly promising pathway for pollutant removal and resource utilization.
基金supported by the National Natural Science Foundation of China (No. 61370188)Beijing Higher Education Young Elite Teacher Project+1 种基金Fundamental Research Funds for the Central Universities (Nos. 2014CLJH09 and 2014GCYY05)Research Funds of Information Security Key Laboratory of Beijing Electronic Science and Technology Institute
文摘Several public-key encryption schemes used to solve the problem of ciphertext data processing on the fly are discussed. A new targeted fully homomorphic encryption scheme based on the discrete logarithm problem is presented. Public-key encryption cryptosystems are classified to examine homomorphic encryption. Without employing techniques proposed by Gentry such as somewhat homomorphic and bootstrapping techniques, or relinearization technique proposed by Brakerski et al., a new method called "Double Decryption Algorithm" is employed in our cryptography to satisfy a fully or targeted fully homomorphic property. Inspired by EIGamal and BGN cryptography, we obtain the desired fully homomorphic property by selecting a new group and adding an extra component to the ciphertext. Proof of semantic security is also demonstrated.
文摘Bismaleimides bearing 2,5-diphenyl-l,3,4- oxadiazole chromophores at para, meta, ortho position and corresponding saturated bissuccinimides were synthe- sized. Several synthetic strategies for these bismaleimides were discussed in detail. Almost no or very weak fluorescence was observed for these bismaleimides, however, the bissuccinimides show a strong fluorescence. The effect of molecular geometry on optical behavior and fluorescence quenching mechanism were investigated by UV-vis absorption and fluorescence emission spectro- scopy. The electron coupling of ground state of p- bismaleimide is stronger than those of m- and o- bismaleimides.p-Bissuccinimide displays increasing fluor- escence quantum yields with red shifts of 22-24 nm, compared to m-bissuccinimide. Polymerizable C=C bonds play a key role in the intramolecular fluorescence quenching.
基金supported by National Natural Science Foundation of China(61370188,61732021)Beijing Municipal Education Commission Scientific Research Project(KM202010015009,KM202110015004)+4 种基金Beijing Institute of Graphic Communication Doctoral Funding Project(27170120003/020,27170122006)The BIGC Project(Ec202201)Beijing Institute of Graphic Communication Research Innovation Team Project(Eb202101)Intramural Discipline Construction Project of Beijing Institute of Graphic Communication(21090121021)Key Educational Reform Project of Beijing Institute of Graphic Communication(22150121033/009).
文摘The cloud’s storage and query of private information have the cryptographic scholar due to the proliferation of cloud computing.In the traditional query mode,the private information stored in the cloud is at risk of being leaked.In order to solve this problem,a cloud ciphertext database system based on homomorphic encryption is a valid workaround.This paper presents a new cloud ciphertext database system model,which is based on the existing ciphertext database mode research and homomorphic properties.This paper also implements a ciphertext database system based on a CRT-based additive homomorphic scheme according to the model.Through theoretical analysis,the model is CPA-level safe and correct.The experimental results show that users can correctly query and download the data in the ciphertext database on the untrusted cloud server through the model,and it has efficiency advantages.
基金supported by the National Natural Science Foundation of China(Grant number U1930203).
文摘In this paper we have studied adsorption and surface reactions of acetylene and ethylene on Co(0001)in detail by temperature desorption spectrum(TDS),X-ray photoelectron spectroscopy(XPS)and ultraviolet photoelectron spectroscopy(UPS).C_(2)H_(4) adsorption at 130 and 300 K followed by subsequent heating mainly forms C_(2) clusters and graphitic carbon,respectively,while C_(2)H_(4) decomposes at 400 and 500 K to form dominant graphitic carbon and carbon adatoms,respectively.C_(2)H_(2) molecularly adsorbs at 130 K but exclusively dehydrogenates upon heating.The resulting C_(2)H_(2)(a)species at low coverages remains stable up to 400 K and then exclusively dehydrogenates into C_(2) clusters,while the resulting C_(2)H_(2)(a)species at high coverages remains stable up to 310 K and then majorly dehydrocyclizates into(C_(2)H)n intermediates with ring structures at 340 K which further dehydrogenates into graphitic carbon,and minorly dehydrogenates into C_(2) clusters.Exposed at 370 K,C_(2)H_(2) dehydrocyclizates into(C_(2)H)n intermediates with ring structures.These temperature and coverage dependent surface reactions of C_(2)H_(2) and C_(2)H_(4) on Co(0001)greatly enrich our fundamental understanding of Co-catalyzed F-T synthesis reaction.