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151.
Tae Hyun Kim Hong Seok Choi Byung Rye Go Joohoon Kim 《Electrochemistry communications》2010,12(6):788-791
Amine-terminated polyamidoamine (PAMAM) dendrimers were immobilized on glassy carbon electrodes (GCEs) via electrochemical oxidation of the terminal amine groups of dendrimers. The electrochemical immobilization of dendrimers was confirmed by cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS). The immobilized dendrimer films were robust and behaved as charge-selective electrochemical gates for oppositely charged redox molecules. The immobilization approach was applied to assemble Au dendrimer-encapsulated nanoparticles (Au DENs, dia. 1.5 ± 0.3 nm) on GCEs, and the resulting Au DEN films showed electrocatalytic activity to hydrazine oxidation. 相似文献
152.
Kathryn R. Rebecchi Jamie L. Wenke Eden P. Go Heather Desaire 《Journal of the American Society for Mass Spectrometry》2009,20(6):1048-1059
We demonstrate herein a method for quantifying glycosylation changes on glycoproteins. This novel method uses MS data of characterized
glycopeptides to analyze glycosylation profiles, and several quality control tests were done to demonstrate that the method
is reproducible, robust, applicable to different types of glycoproteins, and tolerant of instrumental variability during ionization
of the analytes. This method is unique in that it is the first label-free quantitative method specifically designed for glycopeptide
analysis. It can be used to monitor changes in glycosylation in a glycosylation site-specific manner on a single glycoprotein,
or it can be used to quantify glycosylation in a glycoprotein mixture. During mixture analysis, the method can discriminate
between changes in glycosylation of a given protein, and changes in the glycoprotein’s concentration in the mixture. This
method is useful for quantitative analyses in biochemical studies of glycoproteins, where changes in glycosylation composition
can be linked to functional differences; it could also be implemented in the pharmaceutical industry, where glycosylation
profiles of glycoprotein-based therapeutics must be quantified. Finally, quantification of glycopeptides is an important aspect
of glycopeptide-based biomarker discovery, and our quantitative approach could be a valuable asset to this field as well,
provided the compositions of the glycopeptides to be quantified are identifiable using other methods. 相似文献
153.
Kawasaki H Uota M Yoshimura T Fujikawa D Sakai G Kijima T 《Journal of colloid and interface science》2006,300(1):149-154
One-dimensional (1-D) self-assemblies of Pt nanoparticles on a graphite surface have been synthesized via a template-directed sintering process of individual nanoparticles, using nonionic/cationic mixed hemicylindrical micelle templates of dodecyldimethylamine oxide surfactant at graphite/solution interfaces. The dimension and morphology of Pt nanoparticles can be widely controlled by the concentration of Pt ions equivalent to the mixing ratio of nonionic and cationic species in the surfactant micelle. This approach could be extended to fabricate a wide range of self-assembling metallic nanostructures on surfaces using various nonionic/cationic mixed micelle-like self-assemblies carrying metal ions at interfaces, while providing a fundamental insight into a 1-D self-assembly from individual nanoparticles. 相似文献
154.
Gokhroo G Majumder G Abe K Abe K Adachi I Aihara H Anipko D Aushev T Aziz T Bakich AM Balagura V Banerjee S Belous K Bitenc U Bizjak I Blyth S Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Eidelman S Fratina S Gershon T Go A Golob B Gorisek A Ha H Haba J Hayasaka K Hazumi M Heffernan D Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Ishikawa A Itoh R Iwasaki M Iwasaki Y Kang JH Kawai H 《Physical review letters》2006,97(16):162002
We report the first observation of a near-threshold enhancement in the D(0)D[over](0)pi(0) system from B-->D(0)D[over](0)pi(0)Kappa decays using a 414 fb(-1) data sample collected at the Upsilon(4S) resonance. The enhancement peaks at a mass M=3875.2+/-0.7(+0.3)/(-1.6) +/-0.8 MeV/c2 and the branching fraction for events in the peak is B(B-->D(0)D[over](0)pi(0)Kappa)=(1.22+/-0.31(+0.23)/(-0.30))x10(-4). The data were collected with the Belle detector at the KEKB energy-asymmetric e+ e- collider. 相似文献
155.
Chistov R Abe K Abe K Adachi I Aihara H Anipko D Aulchenko V Aushev T Bakich AM Balagura V Barberio E Bay A Bedny I Belous K Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chao Y Chen A Chen KF Chen WT Cheon BG Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Drutskoy A Eidelman S Epifanov D Gabyshev N Garmash A Gershon T Go A Gokhroo G Golob B Gorisek A Ha H Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Hokuue T Hoshi Y Hou S 《Physical review letters》2006,97(16):162001
We report the first observation of two charmed strange baryons that decay into Lambda(c)(+)Kappa(-)pi(+). The broader of the two states is measured to have a mass of 2978.5+/-2.1+/-2.0 MeV/c2 and a width of 43.5+/-7.5+/-7.0 MeV/c2. The mass and width of the narrow state are measured to be 3076.7+/-0.9+/-0.5 MeV/c;{2} and 6.2+/-1.2+/-0.8 MeV/c2, respectively. We also perform a search for the isospin partner states that decay into Lambda(c)(+)Kappa(0)/(s)pi(-) and observe a significant signal at the mass of 3082.8+/-1.8+/-1.5 MeV/c2. The data used for this analysis were accumulated at or near the Upsilon(4S) resonance, using the Belle detector at the e+ e- asymmetric-energy collider KEKB. The integrated luminosity of the data sample used is 461.5 fb(-1). 相似文献
156.
Garmash A Abe K Abe K Adachi I Aihara H Asano Y Aushev T Aziz T Bahinipati S Bakich AM Barbero M Bedny I Bitenc U Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Chuvikov A Dalseno J Danilov M Dash M Dragic J Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Go A Gokhroo G Golob B Gorisek A Ha HC Hara T Hasegawa Y Hastings NC Hayasaka K Hayashii H Hazumi M Hokuue T Hoshi Y Hou S Hou WS Hsiung YB 《Physical review letters》2006,96(25):251803
We report results on a Dalitz analysis of three-body charmless B+/- --> K+/-pi+/-pi+/- decay including searches for direct CP violation. We report the first observation of the decay B+/- --> f2(1270)K+/- with a statistical significance above 6sigma. We also observe first evidence for large direct CP violation in the B+/- --> rho(770)0K+/- channel. The results are obtained with a data sample that contains 386 10(6) BB pairs collected at the Y(4s) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. 相似文献
157.
A Seebeck microprobe (SMP) measurement system has been developed and employed to determine the spatial distribution of the
Seebeck coefficient of a polycrystalline Zn13Sb10 specimen prepared by a gradient freeze (GF) method. The spatial distribution of the Seebeck coefficient strongly reflects
that of the grains observed using an optical polarizing microscope, the magnitude of which ranges from 100 μV/K to 130 μV/K. This fact strongly indicates that the observed spatial distribution of the Seebeck coefficient arises from the anisotropic
Seebeck effect of grains with different crystal orientations in the polycrystalline Zn13Sb10. 相似文献
158.
This study focuses on the finite element analysis of thermoelastic field in a thin circular functionally graded material (FGM) disk subjected to a thermal load and an inertia force due to rotation of the disk. Due to symmetry, the FGM disk is assumed to have exponential variation of material properties in radial direction only. As a result of nonuniform coefficient of thermal expansion (CTE) and nonuniform temperature distribution, the disk experiences an incompatible eigenstrain which is taken into account. Based on the two dimensional thermoelastic theories, the axisymmetric problem is formulated in terms of a second order ordinary differential equation which is solved by finite element method. Some numerical results of thermoelastic field are presented and discussed for an Al2O3/Al FGM disk. The analysis of the numerical results reveals that the thermoelastic field in an FGM disk is significantly influenced by temperature distribution profile, radial thickness of the disk, angular speed of the disk, and the inner and outer surface temperature difference, and can be controlled by controlling these parameters. 相似文献
159.
In this article, the development of a novel technique to fabricate spherical polymeric microcapsules by utilizing microfluidic technology is presented. Atom transfer radical polymerization (ATRP) was employed to synthesize well-defined amphiphilic block copolymers. An organic polymer solution was constrained to adopt the spherical droplets in a continuous water phase at a T-junction microchannel, and the generation of the droplets was studied quantitatively. The flow conditions of two immiscible solutions were adjusted for the successful generation of the polymer droplets. The morphology of the microcapsules was examined. The efficiency of these polymer microcapsules as containers for the storage and controlled release of loaded molecules was evaluated by encapsulating the microcapsules with Congo-red dye and investigating the release performance using temperature controlled UV-VIS spectroscopy. 相似文献
160.
Keita Emura Goichiro Hanaoka Koji Nuida Go Ohtake Takahiro Matsuda Shota Yamada 《Designs, Codes and Cryptography》2018,86(8):1623-1683
In homomorphic encryption schemes, anyone can perform homomorphic operations, and therefore, it is difficult to manage when, where and by whom they are performed. In addition, the property that anyone can “freely” perform the operation inevitably means that ciphertexts are malleable, and it is well-known that adaptive chosen ciphertext (CCA) security and the homomorphic property can never be achieved simultaneously. In this paper, we show that CCA security and the homomorphic property can be simultaneously handled in situations that the user(s) who can perform homomorphic operations on encrypted data should be controlled/limited, and propose a new concept of homomorphic public-key encryption, which we call keyed-homomorphic public-key encryption (KH-PKE). By introducing a secret key for homomorphic operations, we can control who is allowed to perform the homomorphic operation. To construct KH-PKE schemes, we introduce a new concept, transitional universal property, and present a practical KH-PKE scheme with multiplicative homomorphic operations from the decisional Diffie-Hellman (DDH) assumption. For \(\ell \)-bit security, our DDH-based KH-PKE scheme yields only \(\ell \)-bit longer ciphertext size than that of the Cramer–Shoup PKE scheme. Finally, we consider an identity-based analogue of KH-PKE, called keyed-homomorphic identity-based encryption and give its concrete construction from the Gentry IBE scheme. 相似文献