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1.
Physically based simulation of human hair is a well studied and well known problem. But the “pure” physically based representation of hair (and other animation elements) is not the only concern of the animators, who want to “control” the creation and animation phases of the content. This paper describes a sketch-based tool, with which a user can both create hair models with different styling parameters and produce animations of these created hair models using physically and key frame-based techniques. The model creation and animation production tasks are all performed with direct manipulation techniques in real-time.  相似文献   
2.
Although there are many patients with brain tumors worldwide, there are numerous difficulties in overcoming brain tumors. Among brain tumors, glioblastoma, with a 5-year survival rate of 5.1%, is the most malignant. In addition to surgical operations, chemotherapy and radiotherapy are generally performed, but the patients have very limited options. Temozolomide is the most commonly prescribed drug for patients with glioblastoma. However, it is difficult to completely remove the tumor with this drug alone. Therefore, it is necessary to discuss the potential of anticancer drugs, other than temozolomide, against glioblastomas. Since the discovery of cisplatin, platinum-based drugs have become one of the leading chemotherapeutic drugs. Although many studies have reported the efficacy of platinum-based anticancer drugs against various carcinomas, studies on their effectiveness against brain tumors are insufficient. In this review, we elucidated the anticancer effects and advantages of platinum-based drugs used in brain tumors. In addition, the cases and limitations of the clinical application of platinum-based drugs are summarized. As a solution to overcome these obstacles, we emphasized the potential of a novel approach to increase the effectiveness of platinum-based drugs.  相似文献   
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A study of natural convection in an electrochemical system with a Rayleigh number of the order 1010 is presented. Theoretical and experimental results for the unsteady behaviour of the concentration and velocity fields during electrolysis of an aqueous solution of a metal salt are given. The cell geometry is a vertical slot and the reaction kinetics is governed by a Butler-Volmer law. To reduce the effects of stratification, the flush mounted electrodes are located (symmetrically) in the middle parts of the vertical walls. It is demonstrated, both theoretically and experimentally, that a weak stratification develops after a short time, regardless of cell geometry, even in the central part of the cell. This stratification has a strong effect on the velocity field, which rapidly attains boundary layer character. Measured profiles of concentration and vertical velocity at and above the cathode are in good agreement with numerical predictions. For a constant cell voltage, numerical computations show that between the initial transient and the time when stronger stratification reaches the electrode area, the distribution of electric current is approximately steady.List of symbols a i left hand side of equation system - b i right hand side of equation system - c concentration (mol m–3) - c dimensionless concentration - c i concentration of species i' (mol m–3) - c0 initial cell concentration (300 mol m–3) - c 0 dimensionless initial cell concentration - cwall concentration at electrode surface (mol m–3) - dx increment solution vector in Newton's method - D i diffusion coefficient of species i (m2 s–1) - D 1 0.38 × 10–9 m2 s–1 - D 2 0.82 × 10–9 m2 s–1 - D effective diffusion coefficient of the electrolyte (0.52 × 10–9 m2 s–1) - x unit vector in the vertical direction - y unit vector in the horizontal direction - F Faraday's constant (96 487 A s mol–1) - g acceleration of gravity (9.81 m s–2) - i dummy referring to positive (i = 1) or negative (i = 2) ion - f current density (A m–2) - f dimensionless current density - i0 exchange current density (0.01 A m–2) - J ij Jacobian of system matrix - L length of electrode (0.03 m) - N i transport flux density of ion i (mol m–2 s–1) - n unit normal vector - p pressure (Nm–2) - p dimensionless pressure - R gas constant molar (8.31 J K–1 mol–1) - R i residual of equation system - Ra Rayleigh number gL 3 c 0/D (2.54 × 10110) - S c Schmidt number /D (1730) - t time (s) - t dimensionless time - T temperature (293 K) - velocity vector (m s–1) - dimensionless velocity vector - U characteristic velocity in the vertical direction - V ± potential of anode and cathode, respectively - x spatial coordinate in vertical direction (m) - x dimensionless spatial coordinate in vertical direction - x solution vector for c, and - y spatial coordinate in horizontal direction (m) - y dimensionless spatial coordinate in horizontal direction - z i charge number of ion i Greek symbols symmetry factor of the electrode kinetics, 0.5 - volume expansion coefficient (1.24 × 10–4 m3 mol–1) - s surface overpotential - constant in equation for the electric potential (–5.46) - s diffusion layer thickness - scale of diffusion layer thickness - constant relating c/y to the Butler-Volmer law (0.00733) - kinematic viscosity (0.9 × 10–6 m2 s–1)  相似文献   
4.
Nanosized α-Fe2O3 (ca. 50 nm) and Li-Fe composite oxides (ca. 29 nm) powders were synthesized via gel polymer route. The gels were obtained with thermal polymerization of acrylic acid solutions of iron and lithium nitrates. The calcination of these gels at temperatures from 300 °C to 500 °C results in α-Fe2O3 from Fe(NO3)3 precursor and Li-Fe composite oxides Li2O-Fe3O4-LiFeO2 from a mixed precursors of Fe(NO3)3 and LiNO3. Thermal gravimetric analysis, X-ray diffraction and transmission electron microscopy were used to investigate the precursors and products. The electrochemical performance of the Fe-based oxides was also evaluated. After 200 cycles, their capacity can be as high as 1300 mAh/g for α-Fe2O3 and 1400 mAh/g for Li-Fe oxide while the initial capacity loss is as low as 21.8%. The Li-Fe oxide electrodes exhibit better capacity retention than the α-Fe2O3 electrodes. They are interesting negative electrodes for high energy density lithium-ion batteries.  相似文献   
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Nanoscale ferroelectric honeycombs, comprised of vertically aligned PbTiO3 nanotubes, are fabricated by vapor phase reaction between lead acetate‐infiltrated TiO2 nanotubes and PbO vapor. PbTiO3 nanohoneycombs converted by vapor phase reaction at 550°C showed well‐aligned nanoscale structure with alignment angle less than 1° and well‐defined ferroelectric properties with the effective piezoelectric coefficient of 44 pm/V. This novel nanoscale structure is expected to facilitate high efficiency sensing of electromechanical and electrochemical stimuli.  相似文献   
9.
The design and fabrication of solar‐to‐chemical energy conversion devices are enabled through interweaving multiple components with various morphologies and unique functions using a versatile layer‐by‐layer assembly method. Cationic and anionic polyelectrolytes are used as an electrostatic adhesive to assemble the following functional materials: plasmonic Ag nanoparticles for improved light harvesting, upconversion nanoparticles for utilization of near‐infrared light, and polyoxometalate water oxidation catalysts for enhanced catalytic activity. Polyelectrolytes also have an additional function of passivating the surface recombination centers of the underlying photoelectrode. These functional components are precisely assembled on a model photoanode (e.g., Fe2O3 and BiVO4) in a desired order and various combinations without degradation of their intrinsic properties. As a result, the performance of water oxidation photoanodes is synergistically enhanced. This study can enable the design and fabrication of novel solar‐to‐chemical energy conversion devices.  相似文献   
10.
Effective insertion of vertically aligned nanowires (NWs) into cells is critical for bioelectrical and biochemical devices, biological delivery systems, and photosynthetic bioenergy harvesting. However, accurate insertion of NWs into living cells using scalable processes has not yet been achieved. Here, NWs are inserted into living Chlamydomonas reinhardtii cells (Chlamy cells) via inkjet printing of the Chlamy cells, representing a low‐cost and large‐scale method for inserting NWs into living cells. Jetting conditions and printable bioink composed of living Chlamy cells are optimized to achieve stable jetting and precise ink deposition of bioink for indentation of NWs into Chlamy cells. Fluorescence confocal microscopy is used to verify the viability of Chlamy cells after inkjet printing. Simple mechanical considerations of the cell membrane and droplet kinetics are developed to control the jetting force to allow penetration of the NWs into cells. The results suggest that inkjet printing is an effective, controllable tool for stable insertion of NWs into cells with economic and scale‐related advantages.  相似文献   
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