Synthesis and application of alkenylstannanes derived from base-sensitive cyclopropenes

In the presence of stoichiometric potassium fluoride, a range of base-sensitive cyclopropenes undergo direct stannylation using (pentafluoroethyl)tributylstannane. The resulting stannylcyclopropenes serve as precursors to a variety of tetrasubstituted cyclopropenes that might otherwise be difficult to access using alternative methods.     

Studies on pyridylhydrazones derived from biacetyl as analytical reagents

The synthesis, spectral characteristics (ir, uv), hydrolysis, and acid—base properties of biacetyl bis(2-pyridyl)hydrazone (BBPH), biacetylmonoxime-(2-pyridyl)hydrazone (BMPH), and biacetyl mono(2-pyridyl)hydrazone (BPH) have been reported. The behavior of BPH with a variety of metal ions has now been studied by spectrophotometry.     

Studies on the dissolution of carbide fuels

The dissolution of carbide fuels was tried with the aid of various oxidants like H₂O₂, NaBiO₃, (NH₄)₂Ce(NO₃)₆, (NH₄)₂S₂O₈, and AgO in nitric acid medium. During the dissolution, the carbon dioxide liberated has been measured. Among the oxidants studied, H₂O₂ and NaBiO₃ appeared to be more effective for dissolution of carbides. 200–300 mg of sintered uranium carbide sample dissolved within 15 minutes in the presence of oxidants H₂O₂ or NaBiO₃. Mixed carbide sample (70%) was dissolved within 30 min, whereas plutonium carbide required more than one hour. From the resulting solutions uranium and plutonium could be determined by conventional redox methods. More than 97% of plutonium could be recovered and purified from the resulting carbide solutions by conventionally used anion exchange method.     

Analysis of graphene-like activated carbon derived from rice straw for application in supercapacitor

Activated carbons with large surface area, abundant microporosity and low cost are the most commonly used electrode materials for energy storage devices. A very slack activated carbon with ultra-thin two-dimensional (2D) layer structure was prepared by our proposed approach in this work, which includes a pre-treatment process and potassium hydroxide activation at high temperatures.     

Waste-to-resource strategy to fabricate wearable Janus membranes derived from corn bracts for application in personal thermal management

Agricultural waste pollution, one of the serious issues faced by human society, has aroused global attention to environmental sustainability. Resource utilization of agricultural waste is of great significance for the development of energy saving and environmentally friendly materials to settle enormous agricultural waste. Herein, the concept of “turning waste into treasure” was proposed in resource utilization of agricultural waste: biomass cellulose derived from corn bracts was used to fabricate wearable Janus membranes for personal thermoregulation application. Wearable Janus membranes composed of zinc oxide nanosheets layer (ZnO-NSs/CBM) and copper nano-coating layer (Cu-NC/CBM) were prepared using corn bracts cellulose membrane (CBM) as the substrate by hydrothermal method and the subsequent magnetron sputtering technique. More importantly, ZnO-NSs/CBM side has high infrared emissivity and visible reflectivity, which is conducive to releasing a mass of human radiation and enhancing the reflection of sunlight. Janus membranes can achieve radiation cooling when ZnO-NSs/CBM faces outwards. Moreover, Cu-NC/CBM side exhibits low infrared emissivity, which helps to return infrared radiation back to the human body. Janus membranes can access radiation insulation effect when Cu-NC/CBM side faces outwards. In addition, wearable Janus membranes with multi-functionality show an outstanding UV resistance, air permeability, flexibility and mechanical property to offer comfort for the wearer. This study not only provides a waste-to-resource strategy to fabricate wearable Janus membranes by using agricultural waste as raw materials but also demonstrates intriguing applications in personal thermal management thanks to its energy conservation and environmental friendliness.

Graphical abstract

The concept of “turning waste into treasure” was proposed in agricultural resource utilization: cellulose from corn bracts was extracted to fabricate wearable Janus membranes for personal thermoregulation application.

     

Synthesis of a chiral dioxo-cyclam derived from L-phenylalanine and its application to olefin oxidation chemistry

An optically active dioxo-cyclam macrocycle bearing two benzyl side chains derived from phenylalanine has been synthesized; its Ni(II) complex catalyzes the oxidation of olefins using hypochlorite under phase transfer conditions.     

Synthesis of multi-functional epoxides derived from limonene oxide and its application to the network polymers

Bio-based multi-functional epoxides (1) such as bis-, tri-, and tetra-epoxides were synthesized by ene-thiol reactions between limonene oxide and polyhydric thiols. A cross-linking reaction of 1 with branched polyethyleneimine (BPEI) afforded the corresponding network polymers 2 with relatively high thermal resistance in high yields.     

Studies on electrochemical dissolution of sintered molybdenum discs as a potential method for targets dissolution in 99mTc production

Journal of Radioanalytical and Nuclear Chemistry - Electrochemical dissolution of pressed into discs and sintered metallic molybdenum powder with the mass of 712 ± 10 mg...     

Studies on polymers and composites from lignin and fiber derived from sugar cane

Sugarcane fiber (i.e. bagasse) lignin has a larger fraction of aromatics unsubstitution in the ortho position than hardwood or softwood lignin and hence has the greater ability to be derivatized. Furthermore, organosolv lignin has a higher purity than sulfonated and kraft lignins. This work examines the purification of organosolv lignin derived from bagasse and the physico‐chemical properties of the lignin and lignin‐phenol formaldehyde (PF) resin coatings, and composites. The wetability tests have shown that lignin and lignin‐PF resin films are effective water barrier coatings, though the contact angles of lignin‐PF resin films were considerably less than the wax films. The overall mechanical properties (i.e. peak stress, peak strain and modulus) of the bagasse fiber composites were lower than the values obtained with the composites without the inclusion of bagasse fiber. Copyright © 2007 John Wiley & Sons, Ltd.     

Studies on organophosphorus compounds 104. Reaction of carbanions derived from alkylphosphonates

Structural effect of substituents directly bonded to carbanions bearing a phosphorate moiety is examined. Nucleophihc addition of phosphonate carbanion to 1-nitroalkene followed by subsequent reaction with chlorotrimethylsilane leads to a series of 2-isoxazoline based on the formation of an alkene and silyl nitronate as a 1,3-dipole. On the other hand, addition of carbanion derived from isocyanomethylphosphonate to nitroalkene with the formation of nitronate followed by intromolecular cyclization provides substituted phosphoryl pyrroles.     

硝基烷基膦酸酯碳负离子烷基化反应区域选择性研究

α-或β-硝基烷基膦酸酯双负离子与卤代烷反应, 生成碳-烷基化产物, 反应区域选择性取决于硝基膦酸酯的结构, 讨论了可能的反应机理。     

Sol–gel derived nanoporous cerium oxide film for application to cholesterol biosensor

Cholesterol oxidase (ChOx) has been immobilized onto sol–gel derived nano-structured cerium oxide (NS-CeO₂) film deposited on indium-tin-oxide (ITO) coated glass substrate. Phase identification of sol–gel NS-CeO₂ film carried out using X-ray diffraction (XRD) yields reflection peak at 29.4° corresponding to (1 1 1) plane with oriented crystallite (34 nm) along c-axis normal to the substrate. Electrochemical studies reveal that NS-CeO₂ provides electroactive surface for the loading of ChOx and enhances electron transfer rate in the ChOx/NS-CeO₂/ITO bioelectrode. The low value of Michaelis–Menten constant (K_m) obtained as 2.08 mM indicates enhanced ChOx affinity to cholesterol. The observed results show application of sol–gel derived NS-CeO₂ for biosensing without any functionalization.     

Peony pollen derived nitrogen-doped activated carbon for supercapacitor application

Peony pollen is a cheap and readily available biomass material with a relatively high protein content.In this work,it was employed as an N-rich precursor to prepare the nitrogen-doped porous carbon for supercapacitor application.The porous carbon microspheres were prepared through a hydrothermal method and subsequent carbonization process.Notably,ammonium borofruoride and potassium hydroxide were employed respectively as an etchant and an activator to modify the porosity of the materials.The as prepared ANPPCs-700 has a super high BET specific surface area of 824.69 m~2/g.The microstructure,chemical state and electrochemical properties of the product were investigated in detail.The prepared nitrogen-doped carbon microspheres exhibits excellent specific capacity of 209 F/g at a current density of lA/g and remained 92.5% of the initial capacitance after 5000 deep cycles at 5 A/g.