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<jats:p>The magnetic properties and magnetocaloric effect (MCE) of EuTi<jats:sub>1 − <jats:italic>x</jats:italic> </jats:sub>Nb<jats:sub> <jats:italic>x</jats:italic> </jats:sub>O<jats:sub>3</jats:sub> (<jats:italic>x</jats:italic> = 0.05, 0.1, 0.15, and 0.2) compounds are investigated. Owing to electronic doping, parts of Ti ions are replaced by Nb ions, the lattice constant increases and a small number of Ti<jats:sup>4+</jats:sup> (3d<jats:sup>0</jats:sup>) ions change into Ti<jats:sup>3+</jats:sup> (3d<jats:sup>1</jats:sup>). It is the ferromagnetism state that is dominant in the derivative balance. The values of the maximum magnetic entropy change (<jats:inline-formula> <jats:tex-math> <?CDATA $-\Delta {S}_{{\rm{M}}}^{\max }$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mo>−</mml:mo> <mml:mo>Δ</mml:mo> <mml:msubsup> <mml:mi>S</mml:mi> <mml:mi mathvariant="normal">M</mml:mi> <mml:mrow> <mml:mi>max</mml:mi> </mml:mrow> </mml:msubsup> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_29_3_037502_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>) are 10.3 J/kg · K, 9.6 J/kg · K, 13.1 J/kg · K, and 11.9 J/kg · K for EuTi<jats:sub>1 − <jats:italic>x</jats:italic> </jats:sub>Nb<jats:sub> <jats:italic>x</jats:italic> </jats:sub>O<jats:sub>3</jats:sub> (<jats:italic>x</jats:italic> = 0.05, 0.1, 0.15, and 0.2) compounds and the values of refrigeration capacity are 36, 33, 86, and 80 J/kg as magnetic field changes in a range of 0 T–1 T. The EuTi<jats:sub>1 − <jats:italic>x</jats:italic> </jats:sub>Nb<jats:sub> <jats:italic>x</jats:italic> </jats:sub>O<jats:sub>3</jats:sub> (<jats:italic>x</jats:italic> = 0.05, 0.1, 0.15, and 0.2) compounds with giant reversible MCE are considered as a good candidate for magnetic refrigerant working at low-temperature and low-field.</jats:p>

<jats:p>Due to its remarkable electrical and optical properties, graphene continues to receive more and more attention from researchers around the world. An excellent advantage of graphene is the possibility of controlling its charge density, and consequently, the management of its conductivity and dielectric constant, among other parameters. It is noteworthy that the control of these properties enables the obtaining of new optical/electronic devices, which would not exist based on conventional materials. However, to work in this area of science, it is necessary to have a thorough knowledge regarding the electrical/optical properties of graphene. In this review paper, we show these graphene properties very well detailed.</jats:p>

<jats:p>We have studied the dynamic and static processes occurring in disordered multiparticle colloidal Ag aggregates with natural structure and affecting their plasmonic absorption spectra under pico- and nanosecond pulsed laser radiations, as well as the physical origin responsible for these processes. We have shown that depending on the duration of the laser pulse, the mechanisms of laser modification of such aggregates can be associated both with changes in the resonant properties of the particles due to their heating and melting (picosecond irradiation mode) and with the particle shifts in the resonant domains of the aggregates (nanosecond pulses) which depend on the wavelength, intensity, and polarization of the radiation. These mechanisms result in formation of a narrow dip in the plasmonic absorption spectrum of the aggregates near the laser radiation wavelength and affect the shape and position of the dip. The effect of polydispersity of nanoparticle aggregates on laser photochromic reaction has been studied.</jats:p>

<jats:p>The ionized dopants, working as quantum dots in silicon nanowires, exhibit potential advantages for the development of atomic-scale transistors. We investigate single electron tunneling through a phosphorus dopant induced quantum dots array in heavily n-doped junctionless nanowire transistors. Several subpeaks splittings in current oscillations are clearly observed due to the coupling of the quantum dots at the temperature of 6 K. The transport behaviors change from resonance tunneling to hoping conduction with increased temperature. The charging energy of the phosphorus donors is approximately 12.8 meV. This work helps clear the basic mechanism of electron transport through donor-induced quantum dots and electron transport properties in the heavily doped nanowire through dopant engineering.</jats:p>

<jats:p>The influences of the substituent base position on the excited state intramolecular proton transfer fluorescence properties were explored in 2-(2′-hydroxyphenyl)imidazo[1,2-<jats:italic>a</jats:italic>]-pyridine (HPIP) and HPIP’s derivatives (5′Br-HPIP and 6′Br-HPIP). And the density functional theory (DFT) and time-dependent DFT (TD-DFT) methods were used to calculate the molecule structures. The calculated results showed that the influence of 5′Br-HPIP on the fluorescence intensity is stronger than that of 6′Br-HPIP. The fluorescence emission peak of 5′Br-HPIP occurred a blue shift compared with HPIP, and 6′Br-HPIP exhibited an opposite red shift. The change of the fluorescence emission peak was attributed to the decrease of the energy gap from 6′Br-HPIP to 5′Br-HPIP. Our work on the substituent position influence could be helpful to design and develop new materials.</jats:p>

<jats:p>In all-solid-state lithium batteries, the impedance at the cathode/electrolyte interface shows close relationship with the cycle performance. Cathode coatings are helpful to reduce the impedance and increase the stability at the interface effectively. LiTi<jats:sub>2</jats:sub>(PO<jats:sub>4</jats:sub>)<jats:sub>3</jats:sub> (LTP), a fast ion conductor with high ionic conductivity approaching 10<jats:sup>−3</jats:sup> S⋅cm<jats:sup>−1</jats:sup>, is adopted as the coating materials in this study. The crystal and electronic structures, as well as the Li<jats:sup>+</jats:sup> ion migration properties are evaluated for LTP and its doped derivatives based on density functional theory (DFT) and bond valence (BV) method. Substituting part of Ti sites with element Mn, Fe, or Mg in LTP can improve the electronic conductivity of LTP while does not decrease its high ionic conductivity. In this way, the coating materials with both high ionic conductivities and electronic conductivities can be prepared for all-solid-state lithium batteries to improve the ion and electron transport properties at the interface.</jats:p>

<jats:p>The effects of gate oxide traps on gate leakage current and device performance of metal–oxide–nitride–oxide–silicon (MONOS)-structured NAND flash memory are investigated through Sentaurus TCAD. The trap-assisted tunneling (TAT) model is implemented to simulate the leakage current of MONOS-structured memory cell. In this study, trap position, trap density, and trap energy are systematically analyzed for ascertaining their influences on gate leakage current, program/erase speed, and data retention properties. The results show that the traps in blocking layer significantly enhance the gate leakage current and also facilitates the cell program/erase. Trap density ∼ 10<jats:sup>18</jats:sup> cm<jats:sup>−3</jats:sup> and trap energy ∼ 1 eV in blocking layer can considerably improve cell program/erase speed without deteriorating data retention. The result conduces to understanding the role of gate oxide traps in cell degradation of MONOS-structured NAND flash memory.</jats:p>

<jats:p>An anti-radiation structure of InP-based high electron mobility transistor (HEMT) has been proposed and optimized with double Si-doped planes. The additional Si-doped plane under channel layer has made a huge promotion in channel current, transconductance, current gain cut-off frequency, and maximum oscillation frequency of InP-based HEMTs. Moreover, direct current (DC) and radio frequency (RF) characteristic properties and their reduction rates have been compared in detail between single Si-doped and double Si-doped structures after 75-keV proton irradiation with dose of 5 × 10<jats:sup>11</jats:sup> cm<jats:sup>−2</jats:sup>, 1 × 10<jats:sup>12</jats:sup> cm<jats:sup>−2</jats:sup>, and 5 × 10<jats:sup>12</jats:sup> cm<jats:sup>−2</jats:sup>. DC and RF characteristics for both structures are observed to decrease gradually as irradiation dose rises, which particularly show a drastic drop at dose of 5 × 10<jats:sup>12</jats:sup> cm<jats:sup>−2</jats:sup>. Besides, characteristic degradation degree of the double Si-doped structure is significantly lower than that of the single Si-doped structure, especially at large proton irradiation dose. The enhancement of proton radiation tolerance by the insertion of another Si-doped plane could be accounted for the tremendously increased native carriers, which are bound to weaken substantially the carrier removal effect by irradiation-induced defects.</jats:p>

<jats:p>As a large group of cells in a central nervous system, astrocytes have a great influence on ion and energy metabolism in a nervous system. Disorders of neuronal ion and energy metabolism caused by impaired astrocytes play a key role in the pathogenesis of epilepsy. This paper reviews the existing computational models of epileptogenesis resulting from impaired astrocytes and presents several open perspectives with regard to ion and energy metabolism-induced epileptogenesis in a neuron-astrocyte-capillary coupled model.</jats:p>

<jats:p>Hydrogenated amorphous silicon oxide (a-SiO<jats:sub> <jats:italic>x</jats:italic> </jats:sub>:H) is an attractive passivation material to suppress epitaxial growth and reduce the parasitic absorption loss in silicon heterojunction (SHJ) solar cells. In this paper, a-SiO<jats:sub> <jats:italic>x</jats:italic> </jats:sub>:H layers on different orientated c-Si substrates are fabricated. An optimal effective lifetime (<jats:italic>τ</jats:italic> <jats:sub>eff</jats:sub>) of 4743 μs and corresponding implied open-circuit voltage (i <jats:italic>V</jats:italic> <jats:sub>oc</jats:sub>) of 724 mV are obtained on 〈100〉-orientated c-Si wafers. While <jats:italic>τ</jats:italic> <jats:sub>eff</jats:sub> of 2429 μs and i <jats:italic>V</jats:italic> <jats:sub>oc</jats:sub> of 699 mV are achieved on 〈111〉-orientated substrate. The FTIR and XPS results indicate that the a-SiO<jats:sub> <jats:italic>x</jats:italic> </jats:sub>:H network consists of SiO<jats:sub> <jats:italic>x</jats:italic> </jats:sub> (Si-rich), Si– OH, Si– O– SiH<jats:sub> <jats:italic>x</jats:italic> </jats:sub>, SiO<jats:sub>2</jats:sub>≡Si– Si, and O<jats:sub>3</jats:sub> ≡S– Si. A passivation evolution mechanism is proposed to explain the different passivation results on different c-Si wafers. By modulating the a-SiO<jats:sub> <jats:italic>x</jats:italic> </jats:sub>:H layer, the planar silicon heterojunction solar cell can achieve an efficiency of 18.15%.</jats:p>