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81.
The present study investigated a novel milling method for producing amorphous rice starch without adding water. A new type of milling machine was developed (termed the shear and heat milling machine (SHMM)), which is capable of applying mechanical shear and heat during the milling process. The SHMM consisted of a pair of rice mortars attached to a servomotor and a ring heater. The heater was installed on the upper mortar; the temperature of the upper mortar was monitored and controlled by a thermal controller. Wide‐angle X‐ray diffraction (WAXD) analysis was used to determine the crystallinities of starch in rice flour samples produced using the SHMM at different milling temperatures. The WAXD data for milled rice flour that had been heated exhibited no diffraction peaks. This experimental result demonstrates that the developed SHMM produces amorphous rice starch easily by milling with heating without the addition of water. The milling conditions such as the shear and heat applied can be used to control the crystallinity of starch in rice.  相似文献   
82.
A method that combines UV irradiation and pausing was developed to manipulate the regularity and the length scales of the morphology generated by phase separation in full‐interpenetrating polymer networks of polystyrene and poly(methyl methacrylate). Upon increasing the pause time of photopolymerization and photo‐crosslink processes, the morphology gradually changes from hexagonal‐like packing to random structures. The width of the loss tan δ obtained for these phase‐separated materials changes with the morphological regularity, suggesting a potential technique for fabrication of mechanical bandgap materials.

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83.
"This paper aims to investigate the theoretical background of Allen and Sanglier's model, slightly modifying it. We construct a dynamic two-city population model in which there are different types of urban functions in the cities. Population dynamics of both cities are expressed in terms of a system of differential equations of the logistic type, taking account of spatial interaction between them. For this model, both the existence condition and the globally asymptotic stability of the equilibrium state are theoretically explored. Then configurations of equilibrium population distribution that correspond to different combinations of the numbers of types of urban functions in two cities are also examined. Finally, some numerical simulations are done in order to supplement the theoretical considerations."  相似文献   
84.
Cedax is the antibiotic drug of the third generation cephalosporin type. In the Department of Otolaryngology of the University Medical School in Poznań tests were carried out on the effectiveness of this drug in the prevention of perioperative infections (tonsillectomy, adenotomy, septoplastics, nasal polypectomy, mucotomy). The experiment comprised 50 patients who were administered Cedax once a day of the period of five consecutive days, beginning on the day of the surgery. Control group compare 50 patients who did not receive the antibiotic cover. For the comparison of both groups the following symptoms were taken into account: general condition of the patient, body temperature in the first few days after the surgery, the healing of the operative wound (the condition of mucosa, healing "per primam" or "per secundam"), the presence and type of nasal discharge. A high degree of efficiency of ceftibuten has observed.  相似文献   
85.
Monolayers of transition metal dichalcogenides (TMDCs) have attracted a great interest for post‐silicon electronics and photonics due to their high carrier mobility, tunable bandgap, and atom‐thick 2D structure. With the analogy to conventional silicon electronics, establishing a method to convert TMDC to p‐ and n‐type semiconductors is essential for various device applications, such as complementary metal‐oxide‐semiconductor (CMOS) circuits and photovoltaics. Here, a successful control of the electrical polarity of monolayer WSe2 is demonstrated by chemical doping. Two different molecules, 4‐nitrobenzenediazonium tetrafluoroborate and diethylenetriamine, are utilized to convert ambipolar WSe2 field‐effect transistors (FETs) to p‐ and n‐type, respectively. Moreover, the chemically doped WSe2 show increased effective carrier mobilities of 82 and 25 cm2 V?1s?1 for holes and electrons, respectively, which are much higher than those of the pristine WSe2. The doping effects are studied by photoluminescence, Raman, X‐ray photoelectron spectroscopy, and density functional theory. Chemically tuned WSe2 FETs are integrated into CMOS inverters, exhibiting extremely low power consumption ( ≈ 0.17 nW). Furthermore, a p‐n junction within single WSe2 grain is realized via spatially controlled chemical doping. The chemical doping method for controlling the transport properties of WSe2 will contribute to the development of TMDC‐based advanced electronics.  相似文献   
86.
This work introduces a novel formula for calculating the right pseudoinverse, proposed for a class of kinematically redundant robotic limbs with one degree of redundancy. The formula is derived from the Singularity-Consistent method and is expressed as a sum of scalable vector fields parameterized by the desired end link twist. Pseudoinverse properties are ensured by assigning proper vector field intensities. The formula is applied to the IK problem, whereby the end link tracks a degenerate singular path, i.e. a nontangential path that penetrates the workspace boundary, and thus resulting in an unavoidable kinematic singularity. Through this method, the instability of the conventional pseudoinverse solution and the stationary point problem obtained when the solution is stripped from the ill-conditioned denominator is avoided. In addition, the appearance of the ‘inner obstacle’ algorithmic singularity problem known from a previous work can be circumvented. The performance of the method is verified via numerical simulations with an S-R-S-type structure and the Barrett WAM.  相似文献   
87.
Layered -titanate materials, NaxMx/2Ti1−x/2O2 (M=Co, Ni and Fe, x=0.2–0.4), were synthesized by flux reactions, and electrical properties of polycrystalline products were measured at 300–800 °C. After sintering at 1250 °C in Ar, all products show n-type thermoelectric behavior. The values of both d.c. conductivity and Seebeck coefficient of polycrystalline Na0.4Ni0.2Ti0.8O2 were ca. 7×103 S/m and ca. −193 μV/K around 700 °C, respectively. The measured thermal conductivity of layered -titanate materials has lower value than conductive oxide materials. It was ca. 1.5 Wm−1 K−1 at 800 °C. The estimated thermoelectric figure-of-merit, Z, of Na0.4Ni0.2Ti0.8O2 and Na0.4Co0.2Ti0.8O2 was about 1.9×10−4 and 1.2×10−4 K−1 around 700 °C, respectively.  相似文献   
88.
The huge information storage capability of DNA and its ability to self‐assemble can be harnessed to enable massively parallel computing in a small space. DNA‐based logic gates are designed that rely on DNA strand displacement reactions; however, computation is slow due to time‐consuming DNA reassembly processes and prone to failure as DNA is susceptible to degradation by nucleases and under certain solution conditions. Here, it is shown that the presence of a cationic copolymer boosts the speed of DNA logic gate operations that involve multiple and parallel strand displacement reactions. Two kinds of DNA molecular operations, one based on a translator gate and one on a seesaw gate, are successfully enhanced by the copolymer without tuning of computing conditions or DNA sequences. The copolymer markedly reduces operation times from hours to minutes. Moreover, the copolymer enhances nuclease resistance.  相似文献   
89.
The cover image, a 3D stationary salami structure of a green/red/black ternary polymer blend and the separated red and green continuous structure, is by QUI TRAN‐CONG‐MIYATA, based on the Editorial In Focus section: Polymer Research at KIT, Japan, DOI: 10.1002/pi.5248 .

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90.
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