Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
An early divergence in evolution has resulted in two prokaryotic domains, the Bacteria and the Archaea. Whereas the central metabolic routes of bacteria and eukaryotes are generally well-conserved, variant pathways have developed in Archaea involving several novel enzymes with a distinct control. A spectacular example…
Abstract Given their size, in the single‐digit nanometer range, and the versatility of their functionality, dendrimers and other dendritic macromolecules are poised to make a significant contribution to the rapidly expanding fields of nanoscience and nanotechnology. This highlight focuses on nascent applications of de…
The thermal conductivities of individual single crystalline Si/SiGe superlattice nanowires with diameters of 58 and 83 nm were measured over a temperature range from 20 to 320 K. The observed thermal conductivity shows similar temperature dependence as that of two-dimensional Si/SiGe superlattice films. Comparison wit…
Recent progress in chemical vapour deposition and aerosol synthesis of single-walled carbon nanotubes (SWCNTs) is reviewed with an emphasis on the role of metal nanoparticles in the processes. The effect of the various parameters on SWCNT formation is reported on the basis of published experiments. Evolution of the ca…
We have investigated the formation of 10-50 mm long ``ice spikes'' that sometimes appear on the free surface of water when it solidifies. By freezing water under different conditions, we measured the probability of ice spike formation as a function of: 1) the air temperature in the freezing chamber, 2) air motion in t…
We have isolated the gdp1+ gene from Schizosaccharomyces pombe coding for a membrane protein with guanosine diphosphatase (GDPase) activity, which is highly homologous to Golgi GDPases isolated from other yeast species. The gdp1+ product, Gdp1p, displays both GDPase and uridine diphosphatase (UDPase) activities in vit…
The structures of 3,5-bis[4-(diethylamino)benzylidene]-1-methyl-4-piperidone, C(28)H(37)N(3)O, (I), and 3,5-bis[4-(diethylamino)cinnamylidene]-1-methyl-4-piperidone, C(32)H(41)N(3)O, (II), have been characterized. Because of conjugation between donor and acceptor parts, the central heterocycles (including the carbonyl…
Ozonation of norcarane (1) yielded endo and exo norcarane hydrotrioxides (2a, 2b), as characterized by (1)H and (13)C NMR spectroscopy. Further ozonation of the primary decomposition products of these hydrotrioxides, i.e., 2-norcaranols (3), produced the corresponding isomeric 2-norcaranol hydrotrioxides (4a, 4b), and…
The glyoxylate bypass genes aceA1 (isocitrate lyase 1, ICL1), aceA2 (isocitrate lyase 2, ICL2) and aceB1 (malate synthase, MS1) of Ralstonia eutropha HF39 were cloned, sequenced and functionally expressed in Escherichia coli. Interposon-mutants of all three genes (DeltaaceA1, DeltaaceA2 and DeltaaceB1) were constructe…
We report on the time-resolved photoluminescence (PL) properties of terbium ion doped in CdS and ZnS nanocrystals (NCs). The NCs are capped with thiosalcylic acid (TSA) with size ranging from 3 to 5 nm and studied in aqueous solutions. We found that, although the sensitization of terbium PL in both CdS and ZnS nanocry…
1-(4-(N-tert-Butyl-N-aminoxylphenyl))-1H-1,2,4-triazole (NIT-Ph-Triaz) forms isostructural cyclic 2:2 dimeric complexes with M(hfac)(2), M = Mn, Ni, Co, hfac = hexafluoroacetylacetonate. For M = Cu, only a sufficient sample for crystallographic analysis was isolated. For M = Mn, Ni, and Co, the M-NIT exchange is stron…
Donor−acceptor chromophores containing three different types of thiophene-based electron spacers and the same donor (1,3-dithiol-2-ylidene) and acceptor (dicyanomethylene) end groups have been investigated by infrared and vis-near-IR absorption spectroscopies with the aim of elucidating the ability of the heteroquinon…
The epitaxial relationships between two close-packed lattices (face-centered cubic (fcc) and hexagonally close packed (hcp)) and the body-centered cubic (bcc) lattice of spherical micelles were investigated by small-angle X-ray scattering (SAXS) in two in situ shear cells. Two symmetric poly(styrene- b -isoprene) dibl…
[reaction: see text] Disulfides bearing (R)-1,1'-bi-2-naphthol ((R)-BINOL) moieties at each terminal position have been successfully introduced on the surface of Au cluster. Ti-BINOLate complex generated from the obtained monolayer-protected Au cluster (MPC) promoted catalytic asymmetric alkylation of benzaldehyde wit…
A novel series of monodisperse conjugated oligomers were synthesized by inserting varied segments into blue-emitting oligofluorenes to complete the color gamut of light emission. Quantum mechanical calculations revealed that the electron transition dipoles lie largely parallel to the long molecular axes of the central…
This paper reports an experimental study of the NO−char reaction using two types of biomass wheat straw and eucalyptus wood. The experiments were performed in a fixed bed reactor at 1023−1173 K with NO inlet concentrations ranging from 50 to 1500 ppmv. The char was produced in-situ at the reaction temperature, and a s…
Raw electric-arc-produced single-walled carbon nanotubes (SWNTs) were dispersed in organic solvents via a three-step wet chemistry procedure. The soluble sample was purified by continuous dispersion−centrifugation cycles and well-separated SWNTs with high purity were successfully obtained, which enable us to test the…
The first example of a photoactivated probe of intracellular enzymatic activity is described. The caged derivative of a fluorescent protein kinase C peptide-based sensor was prepared by modifying the free hydroxyl group of a phosphorylatable serine moiety with a photolabile appendage that blocks phosphoryl transfer. W…
Water-induced chain dynamics alterations are of paramount importance in many protein-based polymers because they determine and affect to a great extent the temperature dependence of the end properties. In this study, the thermal behavior of the reversible unfolding and refolding of poly(Val-Pro-Gly-Val-Gly) and poly(V…
The antifouling property and biocompatibility of a polyacrylonitrile-based copolymer membrane were improved by the immobilization of poly(ethylene glycol) (PEG) on the membrane surface. The studied membranes were fabricated from poly(acrylonitrile- co -maleic acid), in which the carboxyl groups could be conveniently c…