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排序方式: 共有451条查询结果,搜索用时 25 毫秒
101.
Marcel Popa Nicu Bajan Marcel Ionel Popa Aura Angelica Popa 《Polymer-Plastics Technology and Engineering》2013,52(1):23-28
This paper presents a diffusional system consisting of tolazoline hydrochloride included into a carboxymethylcellulose based hydrogel, showing a high swelling capacity in water. The process kinetics of the drug inclusion into hydrogel as well as of the drug releasing have been studied. The tolazoline hydrochloride release was performed by elution with a simulated biological fluid within the digestive tract, at the small intestine level (pH = 8.2) where the drug is mostly absorbed. The results make evident a zero-order kinetics over the 30–400 min range, which would place the system among those with ‘sustained’ release, with obvious advantages compared with the classical drug administration. 相似文献
102.
Cong Tam Nguyen Nicolas Galanis Guillaume Polidori Stéphane Fohanno Catalin V. Popa Arnaud Le Bechec 《International Journal of Thermal Sciences》2009,48(2):401-411
An experimental investigation was performed to study the heat transfer performance of a 36 nm-Al2O3-particle–water nanofluid in a confined and submerged impinging jet on a flat, horizontal and circular heated surface. The tests were realized for the following ranges of the governing parameters: the nozzle diameter is 3 mm and the distance nozzle-to-heated-surface was set to 2, 5 and 10 mm; the flow Reynolds number varies from 3800 to 88 000, the Prandtl number from 5 to 10, and the particle volume fraction is ranging from 0 to 6%. Experimental data, obtained for both laminar and turbulent flow regimes, have clearly shown that, depending upon the combination of nozzle-to-heated surface distance and particle volume fraction, the use of a nanofluid can provide a heat transfer enhancement in some cases; conversely, for other combinations, an adverse effect on the convective heat transfer coefficient may occur. Within the experimental parameters used, it has been observed that highest surface heat transfer coefficients can be achieved using an intermediate nozzle-to-surface distance of 5 mm and a 2.8% particle volume fraction nanofluid. Nanofluids with high particle volume fractions, say 6% or higher, have been found not appropriate for the heat transfer enhancement purpose under the confined impinging jet configuration. On the other hand, for a very small and a large distance of nozzle-to-heated-surface, it has been observed that the nanofluid use does not provide a perceptible heat transfer enhancement and has, for some particular cases, produced a clear decrease of the convective heat transfer coefficient while compared to that obtained using distilled water. 相似文献
103.
C. Popa S. Fohanno C.T. Nguyen G. Polidori 《International Journal of Thermal Sciences》2010,49(6):901-908
In the present work, a theoretical model based on the integral formalism approach for both laminar and turbulent external natural convection is extended to nanofluids. By using empirical models based on experimental data for computing viscosity and thermal conductivity of water–alumina and water–CuO suspensions, a close attention is first focused on the influence due to increasing the volume fraction of nanoparticles on the heat transfer and then to the transition threshold between laminar and turbulent regimes. The heat transfer is shown to strongly depend on the flow regime and on particle volume fraction. A clear degradation of heat transfer is observed using nanofluids while compared to that of the base-fluid. Moreover, the fact of increasing the particle volume fraction tends to delay the occurrence of the flow transition to turbulence. 相似文献
104.
Riho Kataishi Takayuki Ikeda Toshiki Sasaki Kouhei Toyotaka Daiki Nakamura Hiroyuki Miyake Yuji Iwaki Kazunori Watanabe Yuichi Yanagisawa Hisao Ikeda Harue Nakashima Nobuharu Ohsawa Shingo Eguchi Satoshi Seo Yoshiharu Hirakata Shunpei Yamazaki Daisuke Kurosaki Masakatsu Ohno Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2014,22(8):381-392
In this study, white organic electroluminescent devices with microcavity structures were developed. A flexible high‐resolution active‐matrix organic light‐emitting diode display with low power consumption using red, green, blue, and white sub‐pixels formed by a color‐filter method was fabricated. In addition, a side‐roll touch display was developed in combination with a capacitive flexible touch screen. 相似文献
105.
Stefan‐Ovidiu Dima Tanase Dobre Olga Chetraru Cristian‐Andi Nicolae Catalin‐Ilie Spataru Andrei Sarbu 《Polymer Engineering and Science》2014,54(7):1484-1494
There are presented results regarding a new set of molecularly imprinted polymers (MIPs) based on acrylonitrile:acrylic acid (AN:AA) copolymer matrix. As template, it was used sclareol, an important anticancer bioactive compound, never used before for molecular imprinting. An emerging and insufficient studied MIP preparation method, namely the phase inversion, was used to prepare 0.8 mm spherical sclareol MIPs (S‐MIPs). Three AN:AA copolymers, having the initial monomer ratios 90:10, 80:20, and 70:30, were synthesized by radical copolymerization in emulsion, without emulsifier. After that, each copolymer was dissolved in the presence of the template (sclareol) in dimethylformamide. The imprinting and the morphology of these new materials were analyzed by rheology, elemental analysis, infrared spectroscopy, size exclusion chromatography, thermogravimetric analysis, differential scanning calorimetry, batch rebinding tests, and Scatchard analysis. The conclusion was that the AN:AA‐80:20 matrix proved to be the optimized solution between high rigidity (given by the AN segments) and high affinity for the template (given by AA segments), the average imprinting factor for this system being 2.67. POLYM. ENG. SCI., 54:1484–1494, 2014. © 2013 Society of Plastics Engineers 相似文献
106.
Ryu Komatsu Ryo Nakazato Takeru Sasaki Akio Suzuki Naoyuki Senda Takuya Kawata Yasuhiro Jimbo Tomoya Aoyama Naoto Ohno Susumu Kawashima Hisao Ikeda Shingo Eguchi Yoshiharu Hirakata Shunpei Yamazaki Takashi Shiraishi Seiji Yasumoto Masataka Nakada Masataka Sato Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2015,23(2):41-49
In this study, a 5.9‐inch foldable active‐matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10?6 g/m2?day or less, which improves OLED reliability. With these techniques, we have developed a book‐type display, which is repeatedly foldable like a book, and a tri‐fold display including a display area, which is foldable in three. 相似文献
107.
Mohammad Amin Aliari Andre Beauchamp Tiberiu Popa Eric Paquette 《Computer Graphics Forum》2023,42(2):269-279
We propose an approach for interactive 3D face editing based on deep generative models. Most of the current face modeling methods rely on linear methods and cannot express complex and non-linear deformations. In contrast to 3D morphable face models based on Principal Component Analysis (PCA), we introduce a novel architecture based on variational autoencoders. Our architecture has multiple encoders (one for each part of the face, such as the nose and mouth) which feed a single decoder. As a result, each sub-vector of the latent vector represents one part. We train our model with a novel loss function that further disentangles the space based on different parts of the face. The output of the network is a whole 3D face. Hence, unlike part-based PCA methods, our model learns to merge the parts intrinsically and does not require an additional merging process. To achieve interactive face modeling, we optimize for the latent variables given vertex positional constraints provided by a user. To avoid unwanted global changes elsewhere on the face, we only optimize the subset of the latent vector that corresponds to the part of the face being modified. Our editing optimization converges in less than a second. Our results show that the proposed approach supports a broader range of editing constraints and generates more realistic 3D faces. 相似文献
108.
Popa OP Popa LO Krapal AM Murariu D Iorgu EI Costache M 《International journal of molecular sciences》2011,12(8):5255-5260
Sinanodonta woodiana (Lea, 1834) is a large Unionid species with a real invasion success. It colonized Europe, Central America, the Indonesian Islands and recently North America. The species life cycle involves a larval parasitic stage on freshwater fish species which contributes to the spread of the mussel. In this paper we describe, for the first time, eight polymorphic microsatellite loci for the species Sinanodonta woodiana. The genetic screening of individuals confirmed that all loci were highly polymorphic. The number of alleles per locus ranged from 7 to 14 and the observed heterozygosity ranged from 0.650 to 0.950. These loci should prove useful to study the species population genetics which could help to infer important aspects of the invasion process. 相似文献
109.
Silvia Vasiliu Maria‐Andreea Lungan Stefania Racovita Marcel Popa 《Polymer International》2020,69(11):1066-1080
Two types of porous microparticles based on glycidyl methacrylate, dimethacrylic monomers (ethylene glycol dimethacrylate, diethylene glycol dimethacrylate and triethylene glycol dimethacrylate) and gellan were prepared by two methods. The first method was aqueous suspension polymerization in the presence of N‐butyl acetate as porogenic agent when the crosslinking and grafting reactions were achieved in a single step. The second method was based on the reaction between hydroxyl groups belonging to gellan and the epoxy groups situated on the surface of porous microparticles based on glycidyl methacrylate and dimethacrylic monomers in basic medium. The microparticles with and without gellan were characterized by Fourier transform infrared spectroscopy, SEM, AFM and TGA. Also, the porous structure was investigated in terms of pore volume, porosity and specific surface. The swelling behaviour in aqueous solution with different pH values as well as sorption studies of cefuroxime sodium salt onto porous microparticles were investigated. The presence of gellan in the structure of the microparticles leads to porous materials characterized by higher specific surface areas (Ssp = 78–140 m2 g–1), higher swelling capacities (Sw = 162%–365%) and higher sorption capacities of the drug (qe = 101–147 mg g–1) compared to microparticles without gellan in their structures (Ssp = 73–85 m2 g–1; Sw = 139%–209%; qe = 70–110 mg g–1). © 2019 Society of Chemical Industry 相似文献
110.
The paper presents several new polymer complexes based on poly(2‐hydroxyethyl) methacrylate (P‐HEMA) and transition metals including Y3+, Eu3+, Tb3+ and Dy3+. Red‐, green‐, blue‐ and yellow‐emitting polymer complexes with remarkable photoluminescent (PL) properties, high degree of transparency and excellent processability both in bulk and in thin film were prepared and investigated. In the case of the prepared P‐HEMA–Eu3+ and P‐HEMA–Tb3+ polymer complexes, divinylbenzene was used as a crosslinker resulting a markedly enhanced PL emission, most probably due to the presence of the benzene rings which improve the efficiency of the energy transfer to the cation emissive centres. The prepared polymer complexes were structurally investigated through Fourier transform infrared and X‐ray photoelectron spectroscopies while atomic force microscopy was used to study the morphology of the prepared thin films. Steady‐state fluorescence spectroscopy and absolute PL quantum yield were used for the investigation of the luminescent properties. The impressive PL emission and the convenience of preparation in bulk or thin films could be important arguments for a wide area of applications ranging from photonic conversion materials in optoelectronic devices (light‐emitting diodes, flat‐panel displays) to full‐colour watermarks on special‐purpose papers or PL inks and coatings. © 2019 Society of Chemical Industry 相似文献