Preparation of copper aluminum borate whiskers via flux method

Single‐crystal and uniform copper aluminum borate whiskers have been synthesized by heating a mixture of boric acid, copper sulfate and aluminum sulfate with potassium sulfate as flux at 870 °C for 4 h. The synthesized whiskers exhibit a well‐crystallized, one‐dimensional structure with diameters ranging from 100 nm to 5 μm, lengths from 5 to 100 μm. Heating temperature and flux addition affect the aspect ratio and morphology of the copper aluminum borate whiskers. A possible growth mechanism of the whiskers is proposed. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Generalized fronts in reaction-diffusion equations with bistable nonlinearity

In this paper, we first study the existence of transition fronts (generalized traveling fronts) for reaction-diffusion equations with the spatially heterogeneous bistable nonlinearity. By constructing sub-solution and super-solution we then show that transition fronts are globally exponentially stable for the solutions of the Cauchy problem. Furthermore, we prove that transition fronts are unique up to translation in time by using the monotonicity in time and the exponential decay of such transition fronts.     

Capillary electrophoresis ribosomal RNA single-stranded conformation polymorphism: a new approach for characterization of low-diversity microbial communities

Capillary electrophoresis (CE) has been the principle system for nucleic acid analysis since the early 1990s due to its inherent advantages such as fast analysis time, high resolution and efficiency, minimal sample requirement, high detection sensitivity, and automation. In the past few decades, microbial community fingerprinting methods such as terminal restriction fragment length polymorphism and single-stranded conformation polymorphism (SSCP) have migrated to CE to utilize its advantages over conventional slab gel electrophoresis. Recently, a gel-based direct rRNA fingerprint method was demonstrated. Different from other existing microbial community characterization approaches, this novel approach is polymerase chain reaction free and capable of providing information on the relative abundance of rRNA from individual phylotypes in low-diversity samples. As a gel-based method, it has a long analysis time and relatively large reagent and sample requirements. Here, we addressed these limitations by transferring the RNA fingerprint approach to the CE platform. Analysis time significantly improved from 24?h to 60?min, and the use of a fluorescently labeled hybridization probe as the detection strategy decreased the sample requirement by ten-fold. The combination of fast analysis time, low sample requirement, and sensitive fluorescence detection makes CE-RNA-SSCP an appealing new approach for characterizing low-diversity microbial communities.     

Three New Triterpenoid Saponins from Ardisia crenata

Three new triterpenoid saponins, ardisicrenoside I ( 1 ), ardisicrenoside J ( 2 ), and ardisicrenoside M ( 3 ), along with eight known compounds, were isolated from the roots of Ardisia crenata Sims . Their structures were elucidated as 16α‐hydroxy‐30,30‐dimethoxy‐3β‐O‐{β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl‐(1→4)‐[β‐D ‐glucopyranosyl‐(1→2)]‐α‐L ‐arabinopyranosyl}‐13β,28‐epoxyoleanane ( 1 ), 16α‐hydroxy‐30,30‐dimethoxy‐3β‐O‐{α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl‐(1→4)‐[β‐D ‐glucopyranosyl‐(1→2)]‐α‐L ‐arabinopyranosyl}‐13β,28‐epoxyoleanane ( 2 ), 30,30‐dimethoxy‐16‐oxo‐3β‐O‐{β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl‐(1→4)‐[β‐D ‐glucopyranosyl‐(1→2)]‐α‐L ‐arabinopyranosyl}‐13β,28‐epoxyoleanane ( 3 ), ardisiacrispin A ( 4 ), ardisiacrispin B ( 5 ), ardisicrenoside B ( 6 ), ardisicrenoside A ( 7 ), ardisicrenoside H ( 8 ), ardisicrenoside G ( 9 ), cyclamiretin A‐3β‐O‐β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐arabinopyranoside ( 10 ), and cyclamiretin A‐3β‐O‐α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐arabinopyranoside ( 11 ) by means of chemical and spectral analysis, and their cytotoxicities were evaluated in vitro.     

Two new phenolic compounds from Ardisia gigantifolia

Two new compounds were isolated from the 60% ethanol extract of the dried rhizome of Ardisia gigantifolia Stapf. The structures were elucidated on the basis of spectroscopic methods as （＋）-5-（1,2-dihydroxypentyl）-benzene- 1,3-diol and （-）-5-（1,2- dihydroxypentyl）benzene- 1,3-diol.     

对悬链式超声功率计测量误差的理论探讨

对在使用悬链式超声功率计测量时由于声源指向性所产生的误差进行了理论探讨，并对几个实例进行了数值计算，给出了相应的修正值。     

关于区间估计与假设检验的最优性

本文首先提出了区间估计的另一个优良性因素——虚假度 ,进而建立或疏理了区间估计与假设检验的优良性、最优性概念 ,然后给出了区间估计与假设检验最优性的关系     

Aristolane Sesquiterpenes and Highly Brominated Indoles from the Marine Red Alga Laurencia similis (Rhodomelaceae)

Three new polybrominated 1H‐indoles, compounds 1 – 3 , and three new aristolane sesquiterpenes, compounds 4 – 6 , were isolated from the marine red alga Laurencia similis, together with seven known natural products. Their structures were elucidated on the basis of detailed spectroscopic and mass‐spectrometric analyses, as well as by comparison with literature data.