A new deep-ultraviolet nonlinear optical crystal,Cs_(12)Zn_(4)(B_(5)O_(10))_(4),was synthesized via a high temperature solution method.The crystal structure was solved in the noncentrosymmetric space group(Cc,no.9).Ow...A new deep-ultraviolet nonlinear optical crystal,Cs_(12)Zn_(4)(B_(5)O_(10))_(4),was synthesized via a high temperature solution method.The crystal structure was solved in the noncentrosymmetric space group(Cc,no.9).Owing to the cation size effect,from X_(3)ZnB_(5)O_(10)(X=Na,K,and Rb)to Cs_(12)Zn_(4)(B_(5)O_(10))_(4),the structure changes from centrosymmetric to noncentrosymmetric.Cs_(12)Zn_(4)(B_(5)O_(10))_(4) exhibits a 3D[ZnB_(5)O_(10)]_(∞) network,however,X_(3)ZnB_(5)O_(10)(X=Na,K,and Rb)exhibits a 2D[ZnB_(5)O_(10)]_(∞)layer.It is worth mentioning that Cs_(12)Zn_(4)(B_(5)O_(10))_(4) displays a short cutoff edge(below 185 nm),which is remarkable among the reported Zn-containing NLO crystals.Meanwhile,the compound exhibits a moderate SHG response and melts congruently.In addition,the relationship between its structure and NLO properties was also discussed in detail using the density functional theory(DFT)method.展开更多
Three new bismuth phosphates,Li_(2)ABi(PO_(4))_(2)(A=K,Rb,and Cs),were synthesized through the high-temperature solution method.They all exhibit three-dimensional (3D) [Li_(2)P_(2)O_(8)]^(4-) frameworks built by isola...Three new bismuth phosphates,Li_(2)ABi(PO_(4))_(2)(A=K,Rb,and Cs),were synthesized through the high-temperature solution method.They all exhibit three-dimensional (3D) [Li_(2)P_(2)O_(8)]^(4-) frameworks built by isolated PO_(4) tetrahedra and Li–O chains but crystallize in two different space groups,which can be attributed to the effects of alkali metal cations that control the connection modes of units.Li_(2)KBi(PO_(4))_(2),Li_(2)RbBi(PO_(4))_(2)and Li_(2)CsBi(PO_(4))_(2)show SHG intensities about 5.0,3.1 and 2.5 times that of KDP,respectively,and are all phase-matchable.To the best of our knowledge,Li_(2)KBi(PO_(4))_(2)exhibits the largest SHG response among the bismuth phosphates.The effects of cations on the SHG responses have been discussed in detail.Our results indicate that introduction of the Bi^(3+) cation with large distortion and synclastic arrangement of the Bi–O polyhedra is crucial to produce the large SHG response for phosphate NLO materials.展开更多
With MoS2 as saturable absorber, passive Q-switching and Q-switched mode-locking operations of a Tm-doped calcium lithium niobium gallium garnet（Tm:CLNGG） laser were experimentally demonstrated. The Q-switched laser...With MoS2 as saturable absorber, passive Q-switching and Q-switched mode-locking operations of a Tm-doped calcium lithium niobium gallium garnet（Tm:CLNGG） laser were experimentally demonstrated. The Q-switched laser emitted a maximum average output power of 62 mW and highest pulse energy of 0.72 μJ. Q-switched mode locking was also obtained in the experiment. The research results will open up applications of MoS2 at the mid-infrared wavelength.展开更多
Dentin bonding is a dynamic process that involves the penetration of adhesive resin monomers into the extrafibrillar and intrafibrillar demineralized collagen matrix using a wet-bonding technique.However,adhesive resi...Dentin bonding is a dynamic process that involves the penetration of adhesive resin monomers into the extrafibrillar and intrafibrillar demineralized collagen matrix using a wet-bonding technique.However,adhesive resin monomers lack the capacity to infiltrate the intrafibrillar space,and the excess water that is introduced by the wet-bonding technique remains at the bonding interface.This imperfectly bonded interface is inclined to hydrolytic degradation,severely jeopardizing the longevity of bonded clinical restorations.The present study introduces a dentin bonding scheme based on a dry-bonding technique,combined with the use of extrafibrillar demineralization and a collagen-reactive monomer(CRM)-based adhesive(CBA).Selective extrafibrillar demineralization was achieved using 1-wt%high-molecular weight(MW)carboxymethyl chitosan(CMCS)within a clinically acceptable timeframe to create a less aggressive bonding substance for dentin bonding due to its selectively extrafibrillar demineralization capacity.CMCS demineralization decreased the activation of in situ collagenase,improved the shrinking resistance of demineralized collagen,and thus provided stronger and more durable bonding than traditional phosphoric acid etching.The new dentin bonding scheme that contained CMCS and CBA and used a dry-bonding technique achieved an encouraging dentin bonding strength and durability with low technical sensitivity.This bonding scheme can be used to improve the stability of the resin-dentin interface and foster the longevity of bonded clinical restorations.展开更多
基金completed with the help of the West Light Foundation of the CAS(Grant No.2016-YJRC-2)the National Natural Science Foundation of China(Grant No.U1703127,61835014,and 51425206)+2 种基金the High-level Professional and Technical Personnel of Autonomous region,the Science and Technology Project of Urumqi(Grant No.G161020001)the Xinjiang Key Research and Development Program(Grant No.2016B02021)The authors also express their thanks to the“Fujian Institute of Innovation,CAS”for the support.
文摘A new deep-ultraviolet nonlinear optical crystal,Cs_(12)Zn_(4)(B_(5)O_(10))_(4),was synthesized via a high temperature solution method.The crystal structure was solved in the noncentrosymmetric space group(Cc,no.9).Owing to the cation size effect,from X_(3)ZnB_(5)O_(10)(X=Na,K,and Rb)to Cs_(12)Zn_(4)(B_(5)O_(10))_(4),the structure changes from centrosymmetric to noncentrosymmetric.Cs_(12)Zn_(4)(B_(5)O_(10))_(4) exhibits a 3D[ZnB_(5)O_(10)]_(∞) network,however,X_(3)ZnB_(5)O_(10)(X=Na,K,and Rb)exhibits a 2D[ZnB_(5)O_(10)]_(∞)layer.It is worth mentioning that Cs_(12)Zn_(4)(B_(5)O_(10))_(4) displays a short cutoff edge(below 185 nm),which is remarkable among the reported Zn-containing NLO crystals.Meanwhile,the compound exhibits a moderate SHG response and melts congruently.In addition,the relationship between its structure and NLO properties was also discussed in detail using the density functional theory(DFT)method.
基金s upported by the West Light Foundation of the CAS(Grant No.2016-YJRC-2,2016-QNXZ-A-2)the National Natural Science Foundation of China(Grant No.61835014,51972336)the High-level Professional and Technical Personnel of Autonomous Region,and the Key Research Project of Frontier Science of CAS(Grant No.QYZDB-SSW-JSC049).
文摘Three new bismuth phosphates,Li_(2)ABi(PO_(4))_(2)(A=K,Rb,and Cs),were synthesized through the high-temperature solution method.They all exhibit three-dimensional (3D) [Li_(2)P_(2)O_(8)]^(4-) frameworks built by isolated PO_(4) tetrahedra and Li–O chains but crystallize in two different space groups,which can be attributed to the effects of alkali metal cations that control the connection modes of units.Li_(2)KBi(PO_(4))_(2),Li_(2)RbBi(PO_(4))_(2)and Li_(2)CsBi(PO_(4))_(2)show SHG intensities about 5.0,3.1 and 2.5 times that of KDP,respectively,and are all phase-matchable.To the best of our knowledge,Li_(2)KBi(PO_(4))_(2)exhibits the largest SHG response among the bismuth phosphates.The effects of cations on the SHG responses have been discussed in detail.Our results indicate that introduction of the Bi^(3+) cation with large distortion and synclastic arrangement of the Bi–O polyhedra is crucial to produce the large SHG response for phosphate NLO materials.
基金supported by the National Natural Science Foundation of China (Grant Nos. 61008018 and 11421064)the National Basic Research Program of China (Grant No. 2013CBA01505)
文摘With MoS2 as saturable absorber, passive Q-switching and Q-switched mode-locking operations of a Tm-doped calcium lithium niobium gallium garnet（Tm:CLNGG） laser were experimentally demonstrated. The Q-switched laser emitted a maximum average output power of 62 mW and highest pulse energy of 0.72 μJ. Q-switched mode locking was also obtained in the experiment. The research results will open up applications of MoS2 at the mid-infrared wavelength.
基金This work was supported by National Natural Science Foundation of China(81720108011,81801009,81460107,81970972 and 82001110)the program for Changjiang Scholars and Innovative Research Team in University(No.IRT13051).
文摘Dentin bonding is a dynamic process that involves the penetration of adhesive resin monomers into the extrafibrillar and intrafibrillar demineralized collagen matrix using a wet-bonding technique.However,adhesive resin monomers lack the capacity to infiltrate the intrafibrillar space,and the excess water that is introduced by the wet-bonding technique remains at the bonding interface.This imperfectly bonded interface is inclined to hydrolytic degradation,severely jeopardizing the longevity of bonded clinical restorations.The present study introduces a dentin bonding scheme based on a dry-bonding technique,combined with the use of extrafibrillar demineralization and a collagen-reactive monomer(CRM)-based adhesive(CBA).Selective extrafibrillar demineralization was achieved using 1-wt%high-molecular weight(MW)carboxymethyl chitosan(CMCS)within a clinically acceptable timeframe to create a less aggressive bonding substance for dentin bonding due to its selectively extrafibrillar demineralization capacity.CMCS demineralization decreased the activation of in situ collagenase,improved the shrinking resistance of demineralized collagen,and thus provided stronger and more durable bonding than traditional phosphoric acid etching.The new dentin bonding scheme that contained CMCS and CBA and used a dry-bonding technique achieved an encouraging dentin bonding strength and durability with low technical sensitivity.This bonding scheme can be used to improve the stability of the resin-dentin interface and foster the longevity of bonded clinical restorations.
