谨防夏钓“暗流”

淮河以南广大地区从6月中下旬“入梅”，如果小暑一声雷，半个月黄梅倒过来，捉摸不定，时晴时雨的天气绵延一个月。

Investigation on p-type doping of PBn unipolar barrier InAsSb photodetectors

The lattice-matched XBn structures of InAsSb,grown on GaSb substrates,exhibit high crystal quali⁃ty,and can achieve extremely low dark currents at high operating temperatures(HOT).Its superior performance is attributed to the unipolar barrier,which blocks the majority carriers while allowing unhindered hole transport.To further explore the energy band and carrier transport mechanisms of the XBn unipolar barrier structure,this pa⁃per systematically investigates the influence of doping on the dark current,photocurrent,and tunneling character⁃istics of InAsSb photodetectors in the PBn structure.Three high-quality InAsSb samples with unintentionally doped absorption layers(AL)were prepared,with varying p-type doping concentrations in the GaSb contact layer(CL)and the AlAsSb barrier layer(BL).As the p-type doping concentration in the CL increased,the device’s turn-on bias voltage also increased,and p-type doping in the BL led to tunneling occurring at lower bias voltages.For the sample with UID BL,which exhibited an extremely low dark current of 5×10^(-6) A/cm^(2).The photocurrent characteristics were well-fitted using the back-to-back diode model,revealing the presence of two opposing space charge regions on either side of the BL.

Formononetin Enhances Autophagy Flux in The Penumbra of Cerebral Ischemia and Improves Nerve Damage

Objective Formononetin(FOR),a traditional Chinese medicine,has been widely used for nerve protection and nerve function rehabilitation after cerebral stroke.However,the role of FOR in autophagic lysosome function in cerebral ischemiareperfusion damage has not been investigated.This study aimed to explore whether the therapeutic benefits of FOR were influenced by the regulation of autophagy flux.Methods Male Sprague-Dawley rats were separated into sham,model,and MCAO+FOR(30 mg/kg)groups after undergoing middle cerebral artery occlusion(MCAO)and ischemia-reperfusion(I/R).Then,the brain tissues in the ischemic penumbra were obtained to detect the proteins in autophagic/lysosomal pathway with antibodies of Beclin-1,LC3,SQSTM1/P62,Ubiquitin,LAMP-2,Cathepsin B(CTSB)and Cathepsin D(CTSD)by Western blot and immunofluorescence,respectively.Meanwhile,the therapeutic effectiveness was evaluated by measuring infarct volume,neurological impairments,and neuronal necrosis.Results The findings of this study demonstrate that FOR treatment exhibits a dual effect by enhancing the autophagic activities of Beclin-1 and LC3 in neurons,while simultaneously improving the autophagic clearance function,as evidenced by reinforced lysosomal activities of LAMP-2,CTSB,and CTSD,as well as reduced autophagic accumulation of Ubiquitin and P62 in the MCAO+FOR group compared to the MCAO group.Additionally,7 d of FOR treatment dramatically reduced neurological deficits,infarct volume,and neuronal death caused by cerebral ischemia.Conclusion These findings suggest that the neuroprotective mechanism of FOR therapy in accelerating recovery from ischemic stroke may involve the increase of autophagy flux in the penumbra.

NEW DARK CURRENT SUPPRESSION CMOS READOUT CIRCUIT WITH NOVEL CDS STRUCTURE FOR LARGE FORMAT QWIP FPA

A new Dark Current Suppression (DCS) CMOS readout circuits for large format Quantum-Well-Infrared Photo-detector (QWIP) Focal-Plane-Array (FPA) with novel Correlated-Double-Sampling (CDS) structure based on dynamic source-follower are proposed, which can overcome the drawbacks of the present techniques, such as sensitive to the non-uniformity of the QWIP materials, poor readout noise features, low frame frequency, limited injection efficiency and dynamic range, etc. The dummy is adopted to realize dark current suppression, while the cascode current mirror (with current ratio of 1:10) can increase charge sensitivity and reduce integration time. Through the novel CDS structure, the output waveform is boxcar, and the frame frequency is increased. Simulation results demonstrate that, in high background sense, the proposed DCS circuit can suppress the dark current, achieve good readout performance, such as low power consumption, high charge sensitivity, high resolution, large dynamic range, and insensitive to the non-uniformity of the QWIP materials.

Subthermocline anticyclonic gyre east of Mindanao and its relationship with the Mindanao Undercurrent

The quasi-permanent anticyclonic gyre （ACG） east of Mindanao is a dominant feature of the subthermocline circulation in the southem Philippine Sea, and it is believed closely associated with the continuous northward alongshore flow of the Mindanao Undercurrent （MUC）. In this study, the structure and variability of this ACG were investigated using the 1950-2012 output of the Oceanic General Circulation Model for the Earth Simulator （OFES）, which can reproduce well the structure of the climatological intermediate-layer circulation and satellite-observed sea level variations in the southern Philippine Sea. Between 26.8-27.3 ao, the ACG covers a large area from the Mindanao coast to 131 ~E and from 3~N to 10~N. Its anticyclonic flow structure is unrelated to the surface Halmahera Eddy. The eddy-resolving simulation of the OFES revealed that the ACG consists of two components. The southern ACG （SACG） is centered at -6~N, while the northern ACG （NACG） is centered at -10~N. Seasonal and interannual variations of the ACG are linked to the variations of the northward MUC transport along the Mindanao coast, and the role of the SACG is more important than the NACG. Stronger （weaker） ACGs lead to greater （smaller） MUC transport. On the interannual timescale, the SACG shows a spectrum peak at 4-8 years, while the NACG has enhanced power within the 3-5-year band. A lead-lag correlation analysis indicates that interannual variations of the ACGs and the MUC transport are partly associated with the E1 Nifio-Southern Oscillation. Possible causes for the ACG variability are discussed.

An Interacting Two-Fluid Scenario for Quintom Dark Energy

The Quintom dark energy is a proposal that explains the recent observations that mildly favor the equation of state of dark energy ω crossing -1 near the past. The Quintom model is often constructed by two scalar fields, where one is the quintessence feld and another is the phantom field. The cosmological implication of the coupling of the two fields of the dark energy is out of question worth investigating. However, the consideration of the coupling in the field scenario is somewhat complex thus we propose an interacting two-fluid Quintom scenario for simplicity. The interaction between the two components is parametrized by a constant 71 in this scenario. The cosmological implications of this parametrization are investigated in detail in this paper. Also, a diagnostic for this model is performed by using the statefinder pairs {s, r} and {q, r}.

New dark current component of InGaAs/InP HPDs confirmed by DLTS

The dark current of In_(0.47) Ga_(0.53) As/InP heterojunction photodiodes (HPDs) was analysed. We found that there exists a new dark current component──deep level-assisted tunnelling current.DLTS was used to measure the In_(0.47)Ga_(0.53)As/InP HPDs. An electronic trap which has a thermal activation energy of O.44 eV, level concentration of 3.10×10￣(13)cm￣(-3) and electronic capture cross section of 1.72×10￣(12)cm￣2 has been found.It's existence results in the new tunnelling current.

Exchange between Mafic Enclaves and Host Magma： Case of 1991-1995 Mount Unzen Eruption

Recent eruption of Unzen Volcano in 1991-1995 caught attention of scientists all over the world because of disastrous character of previous one in 1792. Intrusion of andesitic magma to the chamber with rhyolitic magma is proposed to be a trigger for these eruptions. T-P-X parameters of two end-member magmas have been estimated several times, but usually estimations are based on phenocrysts assemblages. New results of this research are based on mafic enclaves and groundmass. These results are significant for magma mixing and mingling theory.

Hole-dominated Fowler–Nordheim tunneling in 2D heterojunctions for infrared imaging

Heterostructures based on diverse two-dimensional(2D)materials are effective for tailoring and further promoting device performance and exhibit considerable potential in photodetection.However,the problem of high-density thermionic carriers can be hardly overcome in most reported heterostructure devices based on type I and type II band alignment,which leads to an unacceptably small Iphoto/Idark and strong temperature dependence that limit the performance of photodetectors.Here,using the MoTe_(2)/h-BN/MoTe_(2)/h-BN heterostructure,we report the hole-dominated Fowler–Nordheim quantum tunneling transport in both on and off states.The state-of-the-art device operating at room temperature shows high detectivity of>10^(8) Jones at a laser power density of<0.3 nW μm^(-2) from the visible to near infrared range.In addition,the fast on–off switching and highly sensitive photodetection properties promise superior imaging capabilities.The tunneling mechanism,in combination with other unique properties of 2D materials,is significant for novel photodetection.

Space-confined growth of high-quality CsBi3I10 lead-free perovskite film for near-infrared photodetectors with high sensitivity and stability

As a lead-free perovskite,CsBi3I10 has attracted significant attention because of its high thermal tolerance and long electron diffusion length.Solution-processed high-performance CsBi3I10 perovskite devices,however,are hindered by the formation of a two-dimensional structure,which results in an extremely high surface roughness and many pinholes.In this paper,we reported a space-confined growth(SCG)method using a single-layer polystyrene(PS)sphere template to obtain high-smoothness,high-crystallinity,and dense CsBi3I10 perovskite films.Compared with traditionally spin-coated CsBi3I10 photodetectors(PDs),the metal-semiconductor-metal PDs made by SCG showed a higher photocurrent,a lower dark current,and a bigger on/off ratio.In addition,the photocurrent of our unencapsulated CsBi3I10 perovskite PDs was not attenuated under long-time illumination.In addition,when the device was stored in air for 30 d,its performance also showed no degradation,demonstrating ultra-high stability.Furthermore,the synthesis was free of antisolvents,such as chlorobenzene and toluene,which is beneficial for the environmentally friendly assembly of the devices.Our strategy opens up a new way to prepare high-quality lead-free perovskite,which may be useful for applications in light-emitting diodes and solar cells.

Constraining the lattice fluid dark energy from SNe Ia,BAO and OHD

Sanchez and Lacombe have developed a lattice fluid theory based on a well-defined statistical mechanical model.Taking the lattice fluid as a candidate of dark energy,we investigate the cosmic evolution of this fluid.Using the combined observational data of Type Ia Supernova(SNe Ia) Union2.1,Baryon Acoustic Oscillations(BAO) data from 6dFGS,SDSS and WiggleZ survey,and Observational Hubble Data(OHD),we find the best fit value of the parameters:A = 0.3 ± 0.2(1σ) ± 0.4(2σ) ± 0.8(3σ) and Ω m = 0.31 ± 0.02(1σ) ± 0.05(2σ) ± 0.07(3σ).The cosmological implications of the model are presented.

Enhanced performance of CdS/CdSe quantum dotsensitized solar cells by long-persistence phosphors structural layer

Light absorption plays an important role in improving the power conversion efficiency(PCE)of quantum dot-sensitized solar cells(QDSSCs).In this study,a multifunctional long-persistence phosphor(LPP)layer was introduced into the CdS/CdSe QDSSCs via a simple doctor blade method.The LPP layer can simultaneously improve the light harvesting and photo charge transfer in CdS/CdSe QDSSCs.As a result,their short-circuit current and corresponding PCE are effectively enhanced.The PCE can reach up to 5.07%,which is about 24%larger than that of the conventional CdS/CdSe QDSSCs without LPP layer.The solar cells can work in dark for a while due to the long-lasting fluorescence of the LPP layer.This research provides an effective way to improve the PCE of QDSSCs,and finds the possibility for all-weather QDSSCs.