The crystal structure and a phase transition of gadolinium orthoborate, GdBO 3 , were studied by electron diffraction and X-ray powder diffraction. GdBO 3 crystallizes in the vaterite structure (LT), in a rhombohedral space group R32 with the lattice constants of a ) 6.6357-(2) Å and c ) 26.706(1) Å. The structure of the LT phase was derived from the hexagonal YBO 3 structure and refined using X-ray powder diffraction data. The structure consists of tetrahedral polyborate group B 3 O 9 9and the gadolinium atoms, located respectively on the 3-fold screw axis and a general position. The material undergoes a first-order phase transition with a large thermal hysteresis. The high-temperature (HT) phase crystallizes in a calcite related structure with the lattice constants of a ) 4.1154(2) and c ) 8.592(1) Å, which consists of planer triangular borate group BO 3 3-. The observed large thermal hysteresis of the phase transition is mainly caused by a structural change of the borate group, from B 3 O 9 9in the LT phase to BO 3 3in the HT phase.

A simple strategy for one-step fabrication of tris(bipyridine)ruthenium(II) (Ru(bpy))-functionalized metal-organic framework (Ru-MOF) thin films using a self-assembly approach assisted by an electrochemical way was introduced. In this protocol, the electrochemically driven cooperative reaction of Ru(bpy) as an electrochemiluminescent (ECL) probe and a structure-directing agent, trimesic acid (Hbtc) as a ligand, and Zn(NO) as the Zn source leads to an one-step and simultaneous synthesis and deposition of the MOF onto the electrode surface. Characterization of the Ru-MOF thin films was performed with scanning electron microscopy, Fourier transform infrared, and X-ray photoelectron spectroscopy. Scanning ion conductance microscopy was specially applied in situ to image the topography and thickness of the Ru-MOF thin films. The Ru-MOF thin films as a sensing platform show excellent ECL behavior because of plenty of Ru(bpy) molecules encapsulated in the frameworks. On the basis of the Ru-MOF modified electrodes, an ultrasensitive label-free ECL immunosensing method for the human heart-type fatty-acid-binding protein has been developed with a wide linear response range (150 fg mL-150 ng mL) and a very low limit of detection (2.6 fg mL). The prepared immunosensor also displayed excellent stability and good specificity in the test of practical samples.

In this work, the coconut shell was preoxidized by hydrogen peroxide, before it was treated by the ammoxidation process and potassium hydroxide activation to synthesize nitrogen-doped porous carbons. The resulting sorbents exhibit significantly higher nitrogen content and narrow microporosity than the control sample without H 2 O 2 pretreatment. Consequently, these sorbents are found to demonstrate high carbon dioxide uptake at 1 bar, such as 4.47 mmol g −1 at 25 °C and 6.79 mmol g −1 at 0 °C. In addition, these sorbents possess high CO 2 /N 2 selectivity, stable reusability, high initial heat of CO 2 adsorption, and high dynamic CO 2 capture capacity under simulated flue gas conditions. These superior CO 2 adsorption properties make them highly competitive among all the carbonaceous adsorbents for CO 2 capture.

The design of cellulose ether-based amphiphiles has been difficult and limited because of the harsh conditions typically required for appending ether moieties to cellulose. Olefin cross-metathesis recently has been shown to be a valuable approach for appending a variety of functional groups to cellulose ethers and esters, provided that an olefin handle for metathesis can be attached. This synthetic pathway gives access to these functional derivatives under very mild conditions and at high efficiency. Modification of ethyl cellulose by metathesis to prepare useful derivatives, for example, for solubility and bioavailability enhancement of drugs by amorphous solid dispersion (ASD), has been limited by the low DS(OH) of commercial ethyl cellulose derivatives. This is problematic because ethyl cellulose is otherwise a very attractive substrate for synthesis of amphiphilic derivatives by olefin metathesis. Herein we explore two methods for opening up this design space for ether-based amphiphiles, for example, permitting synthesis of more hydrophilic derivatives. One approach is to start with the more hydrophilic commercial methyl cellulose, which contains much higher DS(OH) and therefore is better suited for introduction of high DS of olefin metathesis "handles". In another approach, we explored a homogeneous one-pot synthesis methodology from cellulose, where controlled DS of ethyl groups was introduced at the same time as the ω-unsaturated alkyl groups, thereby permitting complete control of DS(OH), DS(Et), and ultimately DS of the functional group added by metathesis. We describe the functionalized derivatives available by these successful approaches. In addition, we explore new methods for reduction of the unsaturation in initial metathesis products to provide robust methods for enhancing product stability against further radical-catalyzed reactions. We demonstrate initial evidence that the products show strong promise as amphiphilic matrix polymers for amorphous solid dispersion and other applications.

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Olefin cross-metathesis (CM) was applied to impart functional variety to a series of cellulose ether derivatives.

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Silkworm (Bombyx mori L.) is one of the important economic insects. Silkworm rearing and silk industry plays an important role in China, India and other developing countries. In the long history of sericultural practice, introduction of silkworm strains with high resistance to diseases has greatly improved cocoon and silk quality and productivity. However, current silkworm breeding is mainly based on traditional method that involves high input of time and labour. In order to increase the selection efficiency and accuracy for future silkworm breeding, it is necessary to establish a molecular marker-assisted selection system. In our study, three silkworm near isogenic lines that had different resistance to nuclear polyhedrosis virus (NPV) were established by means of different hybridization methods. A total of 150 random amplified polymorphic DNA (RAPD) random primers were used to screen molecular markers. Among them, two molecular markers OPA-18 700 and OPY-11 400 were found linked to major genes resistant and susceptible to NPV, respectively. Validity of the molecular markers was proved in F2 populations.