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Climate warming has pronounced impacts on high-elevation regions, including arid Central Asia, and has multiple impacts on the environment. Forests in these mountainous areas provide essential services by regulating regional climate, sequestering carbon, and supporting soil and water conservation. However, trends in forest productivity and their response to climate change remain unclear. To address this knowledge gap, we collected tree cores from five sample plots in the western Tianshan region. We used tree-ring widths to reconstruct net primary productivity (NPP) and investigated the sensitivity of forest NPP to climate change by analysing weather station data and employing LASSO regression to identify climatic factors influencing forest growth. Our results demonstrate that the reconstructed forest NPP effectively captured significant carbon shifts and revealed a non-significant increase in forest productivity associated with climate warming and higher precipitation between 1970 and 2020 at low and middle elevations in the Tianshan mountains. Humidity is the primary limiting factor affecting forest growth in this region. Conversely, the relationship between temperature and forest growth is not consistent as precipitation increases. Our findings suggest that continued warming will exacerbate water stress in forests.

Brookite TiO _2 is considered as one of the excellent candidates in photo- or photo-/electro- chemical applications due to its unique crystalline structure and electronic properties. To achieve an enhanced visible-light-responsive brookite TiO _2 photocatalyst, Zn-doped brookite TiO _2 (ZBT) was in situ synthesized under hydrothermal conditions at 180 °C for 2 h in this research. X-ray diffraction (XRD) verified that the undoped sample was single-phase brookite TiO _2 , while the ZBT samples are mixtures of brookite and anatase because the incorporation of Zn caused brookite to anatase phase transformation. The average particle size of the ZBT samples was smaller than pure brookite TiO _2 and decreased with the increase of Zn amount, indicating that Zn doping inhibited the growth of crystallite. ZBT samples exhibited better photocatalytic activity for the degradation of methylene blue (MB) than pure brookite TiO _2 under visible light irradiation due to the effective separation of electrons and holes by Zn doping. Among the ZBT samples, the 5% ZBT sample exhibited the best photodegradation rate of MB (92.6%) under visible-light irradiation for 2 h, which was attributable to its small particle size (19.78 nm) and the large surface area (67.08 m ^−2 g ^−1 ).

We observed an isostructural phase transition in the solid nitrogen λ -N2 at approximately 50 GPa accompanied by anomalies in lattice parameters, atomic volume and Raman vibron modes. The anomalies are ascribed to a slight reorientation of the nitrogen molecules, which does not seem to affect the monoclinic symmetry (space group P 21/ c). Our ab initio calculations further confirm the phenomena, and suggest an optimized structure for the λ -N2 phase. In addition, a new high-pressure amorphous phase of η ′-N2 was also discovered by a detailed investigation of the pressure-temperature phase diagram of nitrogen with the aim of probing the phase stability of λ -N2. Our result may provide helpful information about the crystallographic nature of dissociation transitions in diatomic molecular crystals (H2, O2, N2, etc). [ABSTRACT FROM AUTHOR]

Non-Hermitian materials can exhibit not only exotic energy band structures but also an anomalous velocity induced by non-Hermitian anomalous Berry connection as predicted by the semiclassical equations of motion for Bloch electrons. However, it is unclear how the modified semiclassical dynamics modifies transport phenomena. Here, we theoretically demonstrate the emergence of anomalous oscillations driven by either an external dc or ac electric field, which arise from non-Hermitian anomalous Berry connection. Moreover, it is a well-known fact that geometric structures of electric wave functions can only affect the Hall conductivity. However, we are surprised to find a non-Hermitian anomalous Berry connection induced anomalous linear longitudinal conductivity independent of the scattering time. We also show the emergence of a second-order nonlinear longitudinal conductivity induced by non-Hermitian anomalous Berry connection, violating a well-known fact of its absence in a Hermitian system with symmetric energy spectra. These anomalous phenomena are illustrated in a pseudo-Hermitian system with large non-Hermitian anomalous Berry connection. Finally, we propose a practical scheme to realize the anomalous oscillations in an optical system. [ABSTRACT FROM AUTHOR]

A novel reflective magnetic field sensor is presented and experimentally demonstrated. The sensing probe is fabricated by splicing a section of uncoated four-core fiber (FCF) between two sections of no-core fibers (NCFs), and the end face of the last NCF is coated by silver. The sensor structure is sealed in a magnetic fluid (MF)-filled capillary, so that the NCF–FCF–NCF magnetic field sensing probe structure is obtained. The NCF is used to excite the high-order modes of the FCF's cladding. Combined with the adjustable refractive index of MF, the sensor is sensitive to the magnetic field and temperature. Experimental results indicate that the presented sensor can measure the low magnetic field and high magnetic field. In the low magnetic field ranges of 0–10 mT and 10–18 mT, the wavelength near 1548 nm varies linearly with the magnetic field intensity, and the sensitivities are −7.43 pm mT−1 and −60 pm mT−1, respectively. The sensitivity of the interference intensity is −0.30782 dB mT−1 in the low magnetic field intensity range of 0–18 mT. The sensor under low magnetic field is also affected by temperature. In the temperature range of 20 °C–70 °C, the temperature sensitivity of the wavelength shift around 1548 nm is 62.33 pm °C−1, and the corresponding sensitivities of the interference intensity are −0.03888 dB °C−1 and −0.02076 dB °C−1 in the range of 30 °C–50 °C and 50 °C–70 °C, respectively. However, the effect of temperature on the sensor in the high magnetic field (18–36 mT) can be ignored. Within the high magnetic field intensity range of 26–36 mT, the sensitivity of the interference intensity near 1598 nm is −1.20993 dB mT−1. The dual-parameter matrix is used to eliminate the cross-sensitivity of temperature in the low magnetic field. This sensor, with the advantages of easy fabrication, high sensitivity and low cost, has the potential application in the magnetic field monitoring. [ABSTRACT FROM AUTHOR]

Doxorubicin (DOX) is a commonly used anticancer drug, but it is inefficient as a therapeutic due to a lack of targeting. Peptide-tuned self-assembly of DOX offers a strategy to improve targeting for greater efficacy. In this work, we designed and prepared an amphiphilic tumor cell-targeting peptide, P14 (AAAAFFFHHHGRGD), able to encapsulate DOX by self-assembly to form tumor cell-targeting and pH-sensitive nano-micelles. The results showed a critical P14-micelle concentration of 1.758 mg l−1 and an average particle size of micelles of 121.64 nm, with entrapment and drug-loading efficiencies of 28.02% ± 1.35% and 12.06% ± 0.59%, respectively. The prepared micelles can release 73.52 ± 1.27% DOX within 24 h in pH 4.5 medium, and the drug cumulative release profile of micelles can be described by the first-order model. Compared with free DOX, the micelles exhibited an increased ability to inhibit tumor cell growth and cause tumor apoptosis in vitro, with IC50 values of DOX and P14-DOX micelles against human breast cancer cells (MCF-7) of 0.91 ± 0.07 and 0.75 ± 0.06 μg ml−1, respectively, and cellular apoptotic rates of DOX and P14-DOX micelles of 70.3% and 42.4%, respectively. Cellular uptake experiments revealed high concentrations of micelles around and inside MCF-7 cells, demonstrating that micelles can target tumor cells. These results indicate the excellent potential for the application of this amphiphilic peptide as a carrier for small-molecule drugs and suggest a strategy for the design of effective anti-tumor drugs. [ABSTRACT FROM AUTHOR]

The optical cavity with high quality factor (Q) has been successfully employed to improve the sensitivity of magnetometer. However, complex system design and tedious data processing hinder the progress of application, since synchronized with other equipments and undergo additional post-processing. To overcome the limitation, we propose a single-loop frequency-locking (SLFL) optomagnetic (OM) signal solution system (SLFL-OMSS). SLFL-OMSS solution obtained a scale factor of 0.17 mV μT−1 and the peak sensitivity is 44.1 fT/Hz1/2 at 200 kHz. SLFL-OMSS reduces the calculating and complexity of the OM sensor system, which provides an efficient way for achieving a high-sensitivity OM sensing. [ABSTRACT FROM AUTHOR]

Higher-order topological insulators have recently witnessed rapid progress in various fields ranging from condensed matter physics to electric circuits. A well-known higher-order state is the second-order topological insulator in three dimensions with gapless states localized on the hinges. A natural question in the context of nonlinearity is whether solitons can exist on the hinges in a second-order topological insulator. Here we theoretically demonstrate the existence of stable solitons localized on the hinges of a second-order topological insulator in three dimensions when nonlinearity is involved. By means of systematic numerical study, we find that the soliton has strong localization in real space and propagates along the hinge unidirectionally without changing its shape. We further construct an electric network to simulate the second-order topological insulator. When a nonlinear inductor is appropriately involved, we find that the system can support a bright soliton for the voltage distribution demonstrated by stable time evolution of a voltage pulse. [ABSTRACT FROM AUTHOR]

An Ni—Al—Co system embedded-atom-method potential is constructed for the γ(Ni)/γ′(Ni3Al) superalloy based on experiments and first-principles calculations. The stacking fault energies (SFEs) of the Ni(Co, Al) random solid solutions are calculated as a function of the concentrations of Co and Al. The calculated SFEs decrease with increasing concentrations of Co and Al, which is consistent with the experimental results. The embedding energy term in the present potential has an important influence on the SFEs of the random solid solutions. The cross-slip processes of a screw dislocation in homogenous Ni(Co) solid solutions are simulated using the present potential and the nudged elastic band method. The cross-slip activation energies increase with increasing Co concentration, which implies that the creep resistance of γ(Ni) may be improved by the addition of Co. [ABSTRACT FROM AUTHOR]

Wireless quantum communication networks transfer quantum state by teleportation. Existing research focuses on maximal entangled pairs. In this paper, we analyse the distributed wireless quantum communication networks with partially entangled pairs. A quantum routing scheme with multi-hop teleportation is proposed. With the proposed scheme, is not necessary for the quantum path to be consistent with the classical path. The quantum path and its associated classical path are established in a distributed way. Direct multi-hop teleportation is conducted on the selected path to transfer a quantum state from the source to the destination. Based on the feature of multi-hop teleportation using partially entangled pairs, if the node number of the quantum path is even, the destination node will add another teleportation at itself. We simulated the performance of distributed wireless quantum communication networks with a partially entangled state. The probability of transferring the quantum state successfully is statistically analyzed. Our work shows that multi-hop teleportation on distributed wireless quantum networks with partially entangled pairs is feasible. [ABSTRACT FROM AUTHOR]

A gate-to-body tunneling current model for silicon-on-insulator (SOI) devices is simulated. As verified by the measured data, the model, considering both gate voltage and drain voltage dependence as well as image force-induced barrier low effect, provides a better prediction of the tunneling current and gate-induced floating body effect than the BSIMSOI4 model. A delayed gate-induced floating body effect is also predicted by the model. [ABSTRACT FROM AUTHOR]

The distributed wireless quantum communication network (DWQCN) has a distributed network topology and transmits information by quantum states. In this paper, we present the concept of the DWQCN and propose a system scheme to transfer quantum states in the DWQCN. The system scheme for transmitting information between any two nodes in the DWQCN includes a routing protocol and a scheme for transferring quantum states. The routing protocol is on-demand and the routing metric is selected based on the number of entangled particle pairs. After setting up a route, quantum teleportation and entanglement swapping are used for transferring quantum states. Entanglement swapping is achieved along with the process of routing set up and the acknowledgment packet transmission. The measurement results of each entanglement swapping are piggybacked with route reply packets or acknowledgment packets. After entanglement swapping, a direct quantum link between source and destination is set up and quantum states are transferred by quantum teleportation. Adopting this scheme, the measurement results of entanglement swapping do not need to be transmitted specially, which decreases the wireless transmission cost and transmission delay. [ABSTRACT FROM AUTHOR]

The neural system characterizes information in external stimulations by different spiking patterns. In order to examine how neural spiking patterns are related to acupuncture manipulations, experiments are designed in such a way that different types of manual acupuncture (MA) manipulations are taken at the ‘Zusanli’ point of experimental rats, and the induced electrical signals in the spinal dorsal root ganglion are detected and recorded. The interspike interval (ISI) statistical histogram is fitted by the gamma distribution, which has two parameters: one is the time-dependent firing rate and the other is a shape parameter characterizing the spiking irregularities. The shape parameter is the measure of spiking irregularities and can be used to identify the type of MA manipulations. The coefficient of variation is mostly used to measure the spike time irregularity, but it overestimates the irregularity in the case of pronounced firing rate changes. However, experiments show that each acupuncture manipulation will lead to changes in the firing rate. So we combine four relatively rate-independent measures to study the irregularity of spike trains evoked by different types of MA manipulations. Results suggest that the MA manipulations possess unique spiking statistics and characteristics and can be distinguished according to the spiking irregularity measures. These studies have offered new insights into the coding processes and information transfer of acupuncture. [ABSTRACT FROM AUTHOR]

The surface treatment of In0.30Ga0.70N photoelectrode in different acid electrolytes (HCl, HBr and a H2SO4 aqueous solution) has been investigated. The highest photocurrent is obtained after the surface treatment in H2SO4 aqueous solution. After H2SO4 treatment, the In0.30Ga0.70N photoelectrode responds to 550 nm and the maximum incident photon-to-current efficiency reaches about 58% under 400-430 nm, which is higher than the previous highest value (42%) on an InGaN photoelectrode. A possible mechanism is also proposed to explain the reason for the highest photocurrent enhancement after H2SO4 surface treatment. The results of the x-ray photoelectron spectroscopy, the inductively coupled atomic emission spectroscope and the electrochemical impedance spectra suggest that the surface segregation layer, as recombination centres of photo-generated holes and electrons, is decreased after H2SO4 surface treatment. [ABSTRACT FROM AUTHOR]

The motion mechanism of the edge dislocation slipping in the cubic plane of Ni3Al under an applied shear stress at different temperatures is studied. At lower temperatures, the edge dislocation moves forward smoothly, and no dislocation lock is formed. At higher temperatures, the motion mechanism of the edge dislocation is controlled by the complex Lomer-Cottrell lock mechanism. Sometimes, the complex Lomer-Cottrell lock tends to transform into a full Lomer-Cottrell lock. The energy barriers of these transformation processes are calculated, and the underlying reason for these transformation processes can be understood in terms of the energy barriers and the applied shear stress. This work gives a good explanation of the in situ observation of the edge dislocation slipping in the cube planes of Ni3Al. [ABSTRACT FROM AUTHOR]

The influence of Re on the propagation of a (0 10)[1 0 1] crack in the Ni/Ni3Al interface, including crack propagation velocity, crack-tip shape, and dislocation emission, is investigated using a molecular dynamics method with a Ni-Al- Re embedded-atom-method potential. The propagation velocity of the crack noticeably decreases at 5K when 3 or 6 at% Re atoms are added into the Ni matrix. At 1033 K, the crack tip becomes blunter and emission of dislocations becomes easier with Re addition, owing to the larger bond strength between Re and Ni atoms. Furthermore, we calculate the unstable stacking energy (ɣus), surface energy (ɣs), and adhesion work (Wad) of the interface. When Re atoms are randomly doped into a Ni matrix, ɣs/ɣus increases correspondingly. This means that Re addition decreases brittleness and improves ductility. The calculation also shows that ɣus is not affected by Re-Ni atomic interaction, and that Re-Re atomic interaction has some effect on ɣus. In addition, Wad increases with Re addition, and a small increase in Wad results in a larger decrease in crack velocity. This indicates that Re-Ni atomic interaction restrains crack propagation velocity at low temperature. [ABSTRACT FROM AUTHOR]

In this paper, sensitized ZnS with visible light driven photocatlytic ability was successfully prepared. The obtained ZnS was characterized by x-ray diffraction, UV-visible diffuse reflectance spectra and Fourier transform infrared spectra. The photocatalytic property of the prepared ZnS was evaluated by decomposing methyl orange (MO). These sensitized ZnS powders with a proper molar ratio showed higher photocatalytic activity than TiO2(P25) under visible light (l > 420 nm) irradiation. A possible explanation for the visible light activity of the prepared ZnS was proposed. [ABSTRACT FROM AUTHOR]

The semiconductor films of SrTiO3, a-Fe2O3 and their heterojunction SrTiO3/a-Fe2O3 were prepared on FTO (SnO2 : F on glass) substrates by the spin-coating method and their structures and properties were characterized by XRD, SEM and photoelectrochemical measurements, respectively. It was observed that the photocurrent and the incident photon to current conversion efficiencies (IPCE or external quantum efficiencies) of the SrTiO3/a-Fe2O3 heterojunction were higher than that of the single SrTiO3 or a-Fe2O3 film, particularly under visible light irradiation. The band structures of SrTiO3 and a-Fe2O3 were calculated. It was found that the charge carriers in a-Fe2O3 had large effective masses while the charge carriers in SrTiO3 had small effective masses at the bottom of the conduction band and at the top of the valence band, which meant weak mobility of holes photo-generated in a-Fe2O3 and strong mobility of holes excited in SrTiO3. As to the SrTiO3/a-Fe2O3 heterojunction, the special valence band structures of SrTiO3 improved the separation efficiency of charge carriers which had been photo-generated in a-Fe2O3. This led to the enhancement of photocurrent densities and external quantum efficiencies in the SrTiO3/a-Fe2O3 heterojunction photoanode. [ABSTRACT FROM AUTHOR]

N-type semiconductor thin films of WO3, Fe2O3and the composite structure of WO3/Fe2O3were prepared on FTO (SnO2?:?F on glass) substrates by the sol-gel method. Their structures and optical properties were characterized by XRD, SEM and UV-Vis spectrometry. Their photoelectrochemical properties were also investigated in a three-electrode cell system. The results showed that the photocurrent of the WO3/Fe2O3film was higher than that of WO3or Fe2O3alone, particularly under visible light illumination (? > 440?nm). In this case there was almost no photocurrent in the WO3film. A reasonable explanation was that the photo-generated electrons could transfer more easily in WO3/Fe2O3than in WO3or Fe2O3alone due to their special conduction band structures. Therefore, the interface between WO3and Fe2O3played an important role in improving the conversion efficiency. [ABSTRACT FROM AUTHOR]

The room-temperature solid-state reactions occurring in the preparation of nanotubes of zinc sulfide are further investigated by x-ray powder diffractometry (XRD) and infra-red (IR) spectrometry measurements, and the nanotube ZnS product obtained is measured by Z-scan technology to investigate the third-order nonlinear optical (NLO) properties. The XRD result suggests that the reactions leading to the formation of the nanotubules have occurred through reaction-controlled to growth-controlled procedures, and the IR result indicates that the procedures involve a coordination effect of the additive DABCO as ligand on the reactant. The result of NLO measurements shows that the nanotube ZnS products obtained have the behaviours of the third-order nonlinear optical properties of both NLO absorption and NLO refraction with self-focusing effects. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate the photoluminescence enhancement in a series of solid solutions, Ca0.9-xNa0.05YxMo1-xVxO4:Eu0.053+ (x = 0.1, 0.3, 0.5) and Ca0.9-yNa0.05BixMo1-yVyO4:Eu0.053+ (v = 0.1, 0.3, 0.5), synthesized by solid-state reaction. By introducing BiVO4 or YVO4, the host lattice absorption and excitation of CaMoO4:Eu3+ in the near-UV region are enhanced arising from the decrease in the bandgap. The emission at 616 nm of Eu3+ under 365 nm excitation has been significantly improved. The emission of 616 nm reaches its maximum when the BiVO4 concentration equals to 3 atom %. The results reveal that modulating the band structure of a phosphor is an effective method to enhance the photoluminescence and to develop a suitable phosphor for near-UV light emission diode. [ABSTRACT FROM AUTHOR]

In this study, we investigate the cross-frequency coupling and functional brain networks in the subjects with temporal lobe epilepsy (TLE) using interictal EEG signals. The phase to phase synchronization within and across frequency bands is calculated and a significant difference between the epilepsy and control groups is observed. Compared with the controls, the epilepsy patients exhibit a stronger within-frequency coupling (WFC) within theta and beta bands, and shows a stronger cross-frequency coupling (CFC) in the delta–alpha and theta–alpha band pairs, but a weakened CFC in alpha–beta band pairs. The weakened coupling between alpha and high frequency band reflects a suppression of phase modulation between the brain regions related to epilepsy. Moreover, WFC and CFC are positively correlated, which is higher in the patients relative to controls. We further reconstruct functional brain connectivity and find that both WFC and CFC networks show small-world properties. For the epilepsy, the small-world efficiency is enhanced in the CFC networks in delta–alpha and theta–alpha band pairs, whereas weakened between alpha and beta bands, which suggests a shift away from the optimal operating point in the epileptic brain with a new balance between WFC and CFC. Our results may help us to understand the important role of information communication across different frequency bands and shed new light on the study of pathology of epilepsy. [ABSTRACT FROM AUTHOR]

The computed tomography of chemiluminescence (CTC) technique is an advanced volumetric imaging technique that can resolve the internal structure of a flame and has found extensive applications in spatiotemporally resolved measurements of complex combustion phenomena. Despite its extensive application, certain improvements are still long-desired to further enhance its performance and reduce measurement uncertainties. Based on the Beer–Lambert law, this work introduces absorption correction into the CTC technique to account for the impact of signal attenuation in the tomographic algorithm. A reverse ray tracing method with distortion correction is proposed to calculate the absorption length within each cubic voxel and the corresponding absorption term, which has been ignored by previous works. To mathematically resolve the coupling process between chemiluminescence attenuation and accumulation during the signal trapping, an alternating-iteration reconstruction algorithm is developed. The results from a proof-of-concept experiment prove the good fidelity of the absorption-corrected CTC technique in solving the 3D distribution of chemiluminescence. [ABSTRACT FROM AUTHOR]

Perovskite photoconductor-type photodetector with metal–semiconductor–metal (MSM) structure is a basic device for photodetection applications. However, the role of electrode interlayer in MSM-type perovskite devices is less investigated compared to that of the pin diode structure. Here, a systematic investigation on the influence of phenyl-C61-butyric acid methyl ester (PCBM) and indene-C60 bisadduct (ICBA) interfacial layers for MSM perovskite photodetectors is reported. It is found that the fullerene-based interlayer significantly enhances the photocurrent of the MSM photodetectors. On one hand, the PCBM interlayer is more suitable for CH3NH3PbI3 photodetector, with the responsivity two times higher than that of the device with ICBA interlayer. The ICBA layer, on the other hand, becomes more effective when the band gap of perovskite is enlarged with bromine composition, denoted as CH3NH3Pb(I1−xBrx)3 ( 1). It is further found that the specific detectivity of photodetectors with ICBA interlayer becomes even higher than those with PCBM when the bromine compositional percentage reaches 0.6 (). [ABSTRACT FROM AUTHOR]

The three-frequency correction method is used to extract the model parameters in a five-element model which includes MOS capacitance C, parallel resistance Rp, interface layer (IL) capacitance Ci, IL resistance Ri, and series resistance Rs. A method for the error analysis of these model parameters has been developed, using error propagation of measured capacitance Cm and resistance Rm. We have applied this error analysis method to a 0.3 mm × 0.3 mm Al/ZrO2/IL/n-Si MOS capacitor with dielectric thickness 35.9 nm. Accumulation capacitances and their errors at various frequency combinations have been calculated to study suitable frequency selection. The errors in the three-frequency correction method depend on selection of the three frequencies (f1 > f2 > f3) and dissipation factor Dm. For large differences between frequencies f1 and f3 (f3/f1 ∼ 0.05– 0.2), the f2 value should be equal to or a little larger than the average value (f3 + f1)/2 to ensure a small error (less than 4%) in spite of large Dm ∼ 0.20–0.31 at f1 = 1.0–1.6 MHz. For three close f1 and f3 (f3/f1 ∼ 0.25–0.6), small ratios for f2/f1 < ∼ 2/3 and f3/f2 < ∼ 2/3 (f3/f1 < 0.44), f2 = (f3 + f1)/2 and small Dm less than ∼0.20 have been suggested to ensure error less than 4%. Considering the error and possible dispersion, the difference between f1 and f3 should be moderate, i.e. f3/f1 = 0.05 ∼ 0.44. For optimal frequency selection, we suggest f3/f1 = ∼0.10 and f2 = (f3 + f1)/2. The frequency selection is not critical for most MOS capacitors, e.g. this sample Al/ZrO2/IL/n-Si capacitor. The three-frequency correction method together with error analysis is effective in extracting accurate accumulation capacitance. [ABSTRACT FROM AUTHOR]

Solar-to-chemical energy conversion is a challenging photochemical reaction for renewable energy storage. In recent decades, photocatalytic H2 evolution has been studied extensively. TiO2 is a well-established semiconductor in the field of photocatalytic H2 production; however, its low efficiency for solar energy utilization, and high photocarrier recombination rate, restrict its photocatalytic efficiency. Here, a series of K-intercalated g-C3N4-modified TiO2 nanobelts (TCN–Kx) with different dosages of K atoms were fabricated using a hydrothermal method followed by a calcination process. XRD, TEM and XPS tests indicate that a tight interfacial connection is formed between K–g-C3N4 and the TiO2 nanobelts. DFT calculations indicated that K dopants prefer to be at the interlayer sites of g-C3N4, suggesting increased charge transfer efficiency. The H2 production efficiency of the TCN–Kx composite materials from water splitting under visible-light irradiation was clearly improved. Steady fluorescence spectroscopy and photocurrent measurements confirmed that the improvement in photocatalytic H2 production activity was due to the superior charge separation and electron transfer efficiency of TCN–Kx composite materials. [ABSTRACT FROM AUTHOR]

Nanotechnology possesses the potential to revolutionize the diagnosis and treatment of tumors. The ideal nanoparticles used for in vivo cancer therapy should have long blood circulation times and active cancer targeting. Additionally, they should be harmless and invisible to the immune system. Here, we developed a biomimetic nanoplatform with the above properties for cancer therapy. Macrophage membranes were reconstructed into vesicles and then coated onto magnetic iron oxide nanoparticles (Fe3O4 NPs). Inherited from the Fe3O4 core and the macrophage membrane shell, the resulting Fe3O4@MM NPs exhibited good biocompatibility, immune evasion, cancer targeting and light-to-heat conversion capabilities. Due to the favorable in vitro and in vivo properties, biomimetic Fe3O4@MM NPs were further used for highly effective photothermal therapy of breast cancer in nude mice. Surface modification of synthetic nanomaterials with biomimetic cell membranes exemplifies a novel strategy for designing an ideal nanoplatform for translational medicine. [ABSTRACT FROM AUTHOR]

An Al/ZrO2/IL/n-Si (IL: interface layer) MOS capacitor has been fabricated by metal organic decomposition of ZrO2 and thermal deposition Al. We have measured parallel capacitance (Cm) and parallel resistance (Rm) versus bias voltage curves (Cm, Rm–V) at different AC signal frequency (f), and Cm, Rm–f curves at different bias voltage. The curves of Cm, Rm–f measurements show obvious frequency dispersion in the range of 100 kHz–2 MHz. The energy band profile shows that a large voltage is applied on the ZrO2 layer and IL at accumulation, which suggests possible dielectric polarization processes by some traps in ZrO2 and IL. Cm, Rm–f data are used for frequency dispersion analysis. To exclude external frequency dispersion, we have extracted the parameters of C (real MOS capacitance), Rp (parallel resistance), CIL (IL capacitance), RIL (IL resistance) and Rs (Si resistance) in a five-element model by using a three-frequency method. We have analyzed intrinsic frequency dispersion of C, Rp, CIL, RIL and Rs by studying the dielectric characteristics and Si surface layer characteristics. At accumulation, the dispersion of C and Rp is attributed to dielectric polarization such as dipolar orientation and oxide traps. The serious dispersion of CIL and RIL are relative to other dielectric polarization, such as border traps and fixed oxide traps. The dispersion of Rs is mainly attributed to contact capacitance (Cc) and contact resistance (Rc). At depletion and inversion, the frequency dispersion of C, Rp, CIL, RIL, and Rs are mainly attributed to the depletion layer capacitance (CD). The interface trap capacitance (Cit) and interface trap resistance (Rit) are not dominant for the dispersion of C, Rp, CIL, RIL, and Rs. [ABSTRACT FROM AUTHOR]

Organolead halide perovskite photodetectors with a simple metal-semiconductor-metal (M-S-M) structure were fabricated. The photodetectors exhibit high optoelectronic performance with a high photoconductive gain in the order of 102 and high responsivity above 150 A W−1. Meanwhile, the photodetectors show a large linear dynamic range of 120 dB, and a short response time of 0.67 µs. The organolead halide perovskite photodetectors with a simple M-S-M structure demonstrate great potential for low-cost and high-performance optoelectronic device applications. [ABSTRACT FROM AUTHOR]

Using molecular dynamics simulation method, the plastic deformation mechanism of Fe nanowires is studied by applying uniaxial tension along the [110] direction. The simulation result shows that the bcc-to-hcp martensitic phase transformation mechanism controls the plastic deformation of the nanowires at high strain rate or low temperature; however, the plastic deformation mechanism will transform into a dislocation nucleation mechanism at low strain rate and higher temperature. Furthermore, the underlying cause of why the bcc-to-hcp martensitic phase transition mechanism is related to high strain rate and low temperature is also carefully studied. Based on the present study, a strain rate-temperature plastic deformation map for Fe nanowires has been proposed. [ABSTRACT FROM AUTHOR]