The concept of group construction vector and independent construction vector for visual cryptography is proposed, and the method based on construction vector is presented for con-structing basis matrices. The general ...The concept of group construction vector and independent construction vector for visual cryptography is proposed, and the method based on construction vector is presented for con-structing basis matrices. The general solutions to construction vectors and the general solutions to k out of n visual cryptographic schemes are obtained. Using the construction vectors, everyone can construct visual cryptographic schemes simply and efficaciously according to the formulas. The concept and the general solutions to construction vector present a good idea for researches on visual cryptographic schemes, including structural properties, the bound of pixel expansion and contrast, and optimal construction.展开更多
Two new tellurite halides,CdPb_(2)Te_(3)O_(8)C_(l2)and Cd_(13)Pb_(8)Te_(14)O_(42)Cl_(14),with cationic layer structures have been synthesized by high-temperature solution method.CdPb_(2)Te_(3)O_(8)C_(l2)crystallizes i...Two new tellurite halides,CdPb_(2)Te_(3)O_(8)C_(l2)and Cd_(13)Pb_(8)Te_(14)O_(42)Cl_(14),with cationic layer structures have been synthesized by high-temperature solution method.CdPb_(2)Te_(3)O_(8)C_(l2)crystallizes in the noncentrosymmetric Aba2 space group,built by[CdPb_(2)Te_(3)O_(8)]cationic layers with Cl atoms.Cd_(13)Pb_(8)Te_(14)O_(42)Cl_(14)crystallizes in the centrosymmetric P space group,constructed by[Cd12Pb4Te8O53]layers,and[Cd_(7)Cl_(6)]octahedra as well as Cl atoms filled the interlayers.In the two compounds,four unique oxyhalide mixed anionic groups,[CdO6Cl],[PbO_(3)Cl_(4)],[PbO4Cl_(4)]and[PbO_(3)Cl5],were discovered.The experimental bands are∼3.89 eV for CdPb_(2)Te_(3)O_(8)C_(l2)and∼3.78 eV for Cd_(13)Pb_(8)Te_(14)O_(42)Cl_(14).Furthermore,the powder second harmonic generation(SHG)response of CdPb_(2)Te_(3)O_(8)C_(l2)is about 0.2×AgGaS_(2)at 2029 nm(×1.1 KDP@1064 nm),which mainly originates from the triangular[TeO_(3)]and distorted[TeO4]units.The results give an insight into the design of new IR optical materials by combining the heavy metal oxyhalide groups with the Te-O units.展开更多
文摘The concept of group construction vector and independent construction vector for visual cryptography is proposed, and the method based on construction vector is presented for con-structing basis matrices. The general solutions to construction vectors and the general solutions to k out of n visual cryptographic schemes are obtained. Using the construction vectors, everyone can construct visual cryptographic schemes simply and efficaciously according to the formulas. The concept and the general solutions to construction vector present a good idea for researches on visual cryptographic schemes, including structural properties, the bound of pixel expansion and contrast, and optimal construction.
基金supported by the S&T Partnership and International S&T Cooperation Program of Shanghai Cooperation Organization(2020E01040)the High-level Talent Project of Xinjiang Uygur Autonomous Region(2020000039)+1 种基金the National Natural Science Foundation of China(52002398 and 22122509)the Xinjiang Key Laboratory of Electronic Information Materials and Devices(2017D04029).
文摘Two new tellurite halides,CdPb_(2)Te_(3)O_(8)C_(l2)and Cd_(13)Pb_(8)Te_(14)O_(42)Cl_(14),with cationic layer structures have been synthesized by high-temperature solution method.CdPb_(2)Te_(3)O_(8)C_(l2)crystallizes in the noncentrosymmetric Aba2 space group,built by[CdPb_(2)Te_(3)O_(8)]cationic layers with Cl atoms.Cd_(13)Pb_(8)Te_(14)O_(42)Cl_(14)crystallizes in the centrosymmetric P space group,constructed by[Cd12Pb4Te8O53]layers,and[Cd_(7)Cl_(6)]octahedra as well as Cl atoms filled the interlayers.In the two compounds,four unique oxyhalide mixed anionic groups,[CdO6Cl],[PbO_(3)Cl_(4)],[PbO4Cl_(4)]and[PbO_(3)Cl5],were discovered.The experimental bands are∼3.89 eV for CdPb_(2)Te_(3)O_(8)C_(l2)and∼3.78 eV for Cd_(13)Pb_(8)Te_(14)O_(42)Cl_(14).Furthermore,the powder second harmonic generation(SHG)response of CdPb_(2)Te_(3)O_(8)C_(l2)is about 0.2×AgGaS_(2)at 2029 nm(×1.1 KDP@1064 nm),which mainly originates from the triangular[TeO_(3)]and distorted[TeO4]units.The results give an insight into the design of new IR optical materials by combining the heavy metal oxyhalide groups with the Te-O units.
