苏皖凹凸棒石粘土中蛋白石矿物学特征

本文对产于苏皖凹凸棒石粘土层中的蛋白石从其物性、形态及结构上进行了研究。研究表明，其蛋白石为ＣＴ－蛋白石。对蛋白石矿物特征的研究为划分对比凹凸棒石粘土层，研究凹凸棒石粘土的成因奠定了基础。     

BaTiO_3∶Tm~(3 )反蛋白石的上转换发光

利用合成蛋白石模板、填充溶胶前驱体、烧结移除模板的方法,制备BaTi O3∶Tm3 的反蛋白石结构.根据实验测量的反射光谱与650nm激光光源激发下的上转换荧光光谱,得到了反蛋白石结构的光子带隙位置以及上转换光谱.由于带隙位置与激发光源位置的重合,与粉末样品的上转换光谱相比,反蛋白石的光谱强度降低,出现了峰位展宽,从而也为光子带隙对于特定电磁波的抑制提供了明显的证据.     

电沉积法制备Cu_2O与ZnO反蛋白石的复合材料

通过两步电沉积法,利用聚苯乙烯(PS)微球作为模板制备Cu2O与ZnO反蛋白石的复合材料.在UV-vis谱中观察到了明显的光子禁带,而且复合材料的光子禁带随ZnO反蛋白石禁带的改变而改变.此外还研究了温度和pH值对制备Cu2O与ZnO反蛋白石的复合材料的影响.     

一种骨料碱活性检测新方法

提出一种新的骨料碱活性检测方法——溶胶-凝胶膨胀法，并用其对蛋白石和天然骨料的碱活性进行了研究，试验结果表明，利用溶胶-凝胶膨胀法，蛋白石表现出明显的碱活性，并且发现在蛋白石掺量为最劣点时的溶液中SiO2含量和SiO2／Na2O摩尔比都达到最值，膨胀量也达到最值。     

光子晶体光催化剂修饰的微反应器制备及其光催化性能研究

采用聚苯乙烯(polystyrene, PS)微球为光子晶体模板,用溶胶-凝胶法在微流控芯片通道中制备TiO₂反蛋白石.在PS蛋白石模板中填充TiO₂溶胶,在500℃下煅烧8 h去除PS模板,得到具有较高光催化性能的TiO₂反蛋白石催化剂.通过考察罗丹明B(RhB)溶液在TiO₂反蛋白石修饰的微反应器中的光催化降解率,分析微反应器的光催化性能.5 mg/L RhB在流速50μL/h、光催化反应时间7 min、光辐照度100 mW/cm²时,降解率达到100%.     

超细蛋白石制备及其性能研究

研究了生产超细微粉的新的工艺设备，并成功地使用这套设备用嫩江蛋白石页岩生产出了超细微粉。应用实验结果表明，该装置生产出的产品具有纳米级的微孔，吸附性很强，细化的蛋白石微粉能较好地与聚丙烯腈等复合，应用广泛。     

反蛋白石结构硫化锑光子晶体的制备

用改进St ber法制备出单分散的SiO2胶球.通过离心沉降法将SiO2胶球有序排列,得到蛋白石结构的SiO2光子晶体,该方法可制备出较大尺寸的蛋白石结构光子晶体.以得到的SiO2光子晶体为模板,通过化学反应向模板间隙填入Sb2S3后再经氢氟酸腐蚀去除二氧化硅胶晶模板,制备出反蛋白石结构硫化锑光子晶体.     

三维有序光子晶体制备及其光学表征

利用重力自组装方式获得了聚苯乙烯(Polystyrene,PS)微球三维有序结构的光子晶体模板.借助毛细管力作用,将BPS(B2O3-P2O5-SiO2)溶胶填充到PS蛋白石模板,制备出层数可控的PS蛋白石及网状BPS反蛋白石模板.吸收及透射光谱表明,光子带隙位置因PS固化时收缩而表现出较大幅度的蓝移.XRD衍射图表明BPS在烧结过程中,随温度升高,BPO4晶相增加,将影响BPS骨架结构的介电常数.     

中国科学家开发出可变色“心脏芯片”

正中国科研团队受变色龙"变色"机制启发,用心肌细胞和水凝胶开发出一种新材料,可用于构建可变色的"心脏芯片",通过芯片颜色变化来监测心脏搏动。最近发表于美国《科学·机器人学》杂志上的一篇论文显示,研究人员将大鼠心肌细胞培养在反蛋白石结构的水凝胶薄膜上,反蛋白石结构水凝胶具有有序的纳米结构,可像蛋白石一样反射特定的波长,表现为鲜艳的结构色。     

纳米银分散的玻璃反蛋白石结构的制备与表征

作者通过溶胶凝胶填充方法、利用胶体晶体为模板,制备纳米银掺杂的氧化硅反蛋白石结构.其中胶体晶体模板通过单分散的胶体微球以垂直沉积法自组装而成.由胶体晶体模板制得的反蛋白石结构拥有与胶体晶体反结构相同的长程有序,并反射不同的色彩,其反射光谱随角度变化并满足布拉格关系.     

MODIFIED OPAL:A NOVEL STABILIZER FOR HYDROGEN PEROXIDE BLEACHING OF PULPS

The possibility of modified opal as the stabilizer of hydrogen peroxide bleaching was investigated. The results showed that the modified opal in place of sodium silicate as the stabilizer of hydrogen peroxide bleaching is feasible. At the same dosage, above 3% ISO can be increased for both wheat straw pulp and deinked pulp. The stabilizing ability of the modified opal to hydrogen peroxide bleaching of pulp is improved markedly. It is favorable for bleaching to increase temperature and time within a permissive extent. The suitable process conditions are 10% of pulp consistency, 3% of hydrogen peroxide, 1.5% of sodium hydroxide, 3% of the modified opal, 70℃ and 60 min when the modified opal is used as the stabilizer of hydrogen peroxide bleaching. At these conditions, the brightness gain can reach about 16% ISO for wheat straw pulp. In addition, it is favorable for bleaching to add a little magnesium sulfate when the modified opal is used as the stabilizer of hydrogen peroxide bleaching, the brightness of pulp can increase I%ISO if0.05% of magnesium sulfate is added. The cost analysis indicated that the modified opal is superior to sodium silicate as the stabilizer of hydrogen peroxide bleaching in economical aspect and has further the potential of market development.     

Resolving the 'opal paradox' in the Southern Ocean

In the Southern Ocean, high accumulation rates of opal--which forms by precipitation from silica-bearing solutions--have been found in the sediment in spite of low production rates of biogenic silica and carbon in the overlying surface waters. This so-called 'opal paradox' is generally attributed to a higher efficiency of opal preservation in the Southern Ocean than elsewhere. Here we report biogenic silica production rates, opal rain rates in the water column and opal sediment burial rates for the Indian Ocean sector of the Southern Ocean, which show that the assumed opal paradox is a result of underestimated opal production rates and overestimated opal accumulation rates. Our data thus demonstrate that the overall preservation efficiency of biogenic opal in this region is substantially lower than previously thought, and that it lies within a factor of two of the global mean. The comparison of our revised opal preservation efficiencies for the Southern Ocean with existing values from the equatorial Pacific Ocean and the North Atlantic Ocean shows that spatial differences in preservation efficiencies are not the primary reason for the differences in sedimentary opal accumulation. The reconciliation of surface production rates and sedimentary accumulation rates may enable the use of biogenic opal in the reconstruction of palaeo-productivity when the factors that affect the Si/C ratio are better understood.     

Silica photonic crystals with quasi-full band gap in the visible region prepared in ethanol

Monodisperse silica spheres of 252 nm with a standard deviation of 5.7% are prepared by Stber method. By compari-son of both of media, ethanol instead of water is used to assemble opal, and the artiflcial opal has been prepared by the sedimentation inethanol of silica spheres. The structure of the opal prepared has been examined and discussed. The results show that the artificial opal hasa structure similar to the face-centered cubic (fcc) type packed system with silica spheres. Transmission measurements of the artificial opalhave been conducted, which shows that the artificial opal is quasi-full band gap silica photonic crystals in the visible region.     

Template－synthesized opal hydrogels

Opal hydrogels could be synthesized with polymer inverse opal template. A pH responsive opal N-iso-propylacrylamide/acrylic acid copolymerized hydrogel was prepared as an example. The ordered structure and response to pH were investigated. Through the sol-gel process of tetrabutyl titanate, opal titania was obtained with the opal hydrogel template.     

Quaternary high-resolution opal record and its paleoproductivity implication at ODP Site 1143,southern South China Sea

The correlation of opal content and MAR with oxygen isotopic records of benthonic foraminifera at Site 1143, southern South China Sea indicates that,since about 900 ka,the increasing opal content and MAR during the interglacial periods is inferred to reflect the bigher surface productivity ,for the intensified summer monsoon during the interglacial periods would result in the enhanced upwelling and nutrient supply,Time-sequence spectral analyses of oxygen isotopic record ,opal content and MAR at intervals of 0-900 ka reveal that the changes of surface productivity were dominantly forced by the variations of the earth orbital cycles.     

光响应调控的SiO_2反蛋白石光子晶体

利用牺牲模板法制备了SiO2反蛋白石型光子晶体,用扫描电子显微镜对其表面形貌及其厚度进行了表征;并在其孔隙中填充了具有光响应的有机染料分子螺吡喃衍生物,通过紫外-可见反射光谱监测了光诱导下染料分子构型转变过程中光子晶体光子禁带的变化。结果表明在不同波长的光照下,最大反射波长处的反射率可以进行可逆地控制,并实现了光诱导下对染料分子荧光的调控。     

蛋白石薄膜及其异质结构的可控制备

利用毛细管辅助沉积方法制备了厚度及膜内裂缝的形状、分布可控的三维蛋白石薄膜。讨论了所得薄膜光学性质以及膜的形态特性与薄膜厚度之间的关系。用同样的方法制备了由不同粒径的球体基元晶体带构成的横向交替异质结构。