Novel Fused Taper 1x4 Star Coupler for Full-Band Operation

A novel fused taper 1x4 coupler for full-band operation is proposed. Wavelength flattened characteristics and excellent branching uniformity less than 0.4 dB have been achieved in wavelength range from 1200 nm to 1700 nm.     

Modified polysulfones. VI. Preparation of polymer membrane materials containing benzimine and benzylamine groups as precursors for molecularly imprinted sensor devices

A modified polysulfone containing benzylamine groups was synthesized as a reactive membrane material. Polysulfone was activated at the ortho‐sulfone site by direct lithiation with n‐butyllithium, and the resulting lithiated polysulfone was then reacted with benzonitrile; this yielded a polymer with pendant benzimine groups. The structure was confirmed by NMR and IR spectroscopy and by the transformation of imine to ketone by acid hydrolysis. The polymeric benzimine was also reduced to benzylamine with sodium cyanoborohydride in an acidic medium. The structure and degree of substitution of both benzylamine derivatives were determined by NMR and IR spectroscopy. The modified polysulfone containing benzylamine groups initiated the polymerization of N‐carboxyanhydride of γ‐benzyl‐L ‐glutamate [Glu(OBzl)–NCA]. The side‐chain oligopeptide of Glu(OBzl)–NCA attached to polysulfone was converted into molecular recognition sites. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1316–1329, 2003     

Kei2 ECR离子源C4+、C5+束流的最佳结果

With the prototype ECR ion source for the next carbon therapy facility in Japan a new series of measurements has been performed in order(a)to find the highest beam currents of C~(4 ) ions,and(b)to study the effect of"special"gas-mixing by using a chemical compound as a feed gas.An isotopic effect has been found in a previous experiment:with deuterated methane(CD_4 gas) the C~(5 ) beam currents are about 10% higher than with regular methane(CH_4 gas).For butane gases(C_4D_(10) and C_4H_(10) respectively)the isotopic effect for C~(5 ) production is even stronger(>15%).For production of C~(4 ) ions the isotopic effect appears to be absent.It turns out that the relative amount of carbon is much more important:acetylene gives 15% higher C~(4 ) current than butane,which in turn gives about 10% higher C~(4 ) ion currents than methane.     

Development of the single-cell MALDI-TOF (matrix-assisted laser desorption/ionization time-of-flight) mass-spectroscopic assay.

MALDI-TOF mass spectrometry was used to detect intracellular molecules from a single intact cell on monolayers of other cells. Intracellular molecules, e.g., histamine, were gradually increased in a mouse bone marrow-derived mast cell by a maturation process. A single cell was captured by a microsuction pipette, and the mass spectra of intracellular histamine were measured directly. Finally, the time course of the intracellular molecular contents and the maturation stage from a single cell were estimated.     

The facile synthesis of graphitic carbon nitride from amino acid and urea for photocatalytic H<Subscript>2</Subscript> production

We report on the facile synthesis of g-C₃N₄ based polymers by co-condensing urea with glycine for photocatalytic hydrogen evolution. The as-prepared photocatalysts were then characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, UV–Vis diffuse reflectance spectroscopy, photoluminescence emission spectrometry, electron paramagnetic resonance spectrometry and transmission electron microscopy. Compared with pristine g-C₃N₄, obtained from direct pyrolysis of urea, the CNU-G₅ photocatalyst showed largely enhanced photocatalytic H₂ activities about 75 μmol h^?1, which is 5 times higher than of the pristine CNU. The enhanced activities are ascribed to the larger specific area surface, strengthened optical absorption and improved electron transport ability. Our work opens up a new pathway for the synthesis graphitic carbon nitride photocatalysts with glycine modification to enhance photocatalytic activities.     

Affine-invariant strictly cyclic Steiner quadruple systems

To determine the spectrum of Steiner quadruple systems (SQS) admitting a specific automorphism group is of great interest in design theory. We consider a strictly cyclic SQS which is invariant under the affine group, called an AsSQS. For the applications of designs of experiments, group testing, filing schemes, authentication codes, and optical orthogonal codes for CDMA communication, etc., a larger automorphism group containing the cyclic group may work efficiently for the procedures of generating and searching blocks in a design with less storage and time. In this paper, constructions and a necessary condition for the existence of an AsSQS are investigated. For a prime \(p \equiv 1 \;({\hbox {mod}}\; 4)\), Direct Construction A establishes an AsSQS(2p), provided that a 1-factor of a graph exists, where the graph is defined by using a system of generators of the projective special linear group PSL(2, p). Direct Construction B gives an AsSQS(2p) which is 2-chromatic, provided that a rainbow 1-factor of a specific hypergraph exists. Accordingly, by proposing two recursive constructions of an AsSQSs\((2p^m)\) for a positive integer m, we prove that an AsSQS\((2p^m)\) exists, if the criteria developed for an AsSQS(2p) are satisfied. We verified the claim and found that an AsSQS\((2p^m)\) exists for every prime \(p \equiv 1 \;({\hbox {mod}}\; 4)\) with \(p < 10^5\) and any positive integer m.     

Memristive operations demonstrated by gap-type atomic switches

We demonstrate memristive operations using gap-type Ag₂S atomic switches, in which the growth and shrinkage of an Ag protrusion are controlled by using solid-electrochemical reactions. In addition to conventional memristive operations such as those proposed and demonstrated by resistive random-access memories (ReRAMs) using metal oxide compounds, gap-type Ag₂S atomic switches also show new types of memristive operations by storing information from input signals without changing their output until a sufficient number of signals are inputted. The new types of memristive operations resemble the learning process seen in neuroplasticity, where changes occur in the organization of the human brain as a result of experience.     

Dynamic Enumeration of All Mixed Cells

The polyhedral homotopy method, which has been known as a powerful numerical method for computing all isolated zeros of a polynomial system, requires all mixed cells of the support of the system to construct a family of homotopy functions. The mixed cells are reformulated in terms of a linear inequality system with an additional combinatorial condition. An enumeration tree is constructed among a family of linear inequality systems induced from it such that every mixed cell corresponds to a unique feasible leaf node, and the depth-first search is applied to the enumeration tree for finding all the feasible leaf nodes. How to construct such an enumeration tree is crucial in computational efficiency. This paper proposes a dynamic construction of an enumeration tree, which branches each parent node into its child nodes so that the number of feasible child nodes is expected to be small; hence we can prune many subtrees which do not contain any mixed cell. Numerical results exhibit that the proposed dynamic construction of an enumeration tree works very efficiently for large scale polynomial systems; for example, it generated all mixed cells of the cyclic-15 problem for the first time in less than 16 hours.