Study on Enzymatic Hydrolysis Technology and Antioxidant Activity of Glutinous Rice Glutinous Enzymatic Processes and Antioxidant Activity

[ Objective] This study aimed to investigate enzymatic hydrolysis technology of glutinous rice and the oxidation resistance activity of the enzymatic hydrolysis solution. [ Method ] White glutinous rice was hydrolyzed using four kinds of proteases including neutral protease, alkaline protease, papain and trypsin. Using the scavenging rate of hydroxyl radical （ ·OH） as an indicator and appropriate protease as hydrolytic enzyme, the effects of protein substrate concentration, enzyme dosage, enzymatic hydrolysis temperature and initial pH on the abilities of proteases to scavenge hydroxyl radical from enzymatic hydrolysis solution of glutinous rice were investigated. Based on single-factor test, L9 （34） orthogonal experimental design was adopted, to determine the optimal enzymatic hydrolysis condi- tions leading to the highest oxidation resistance activity of enzymatic hydrolysis solution. [ Result] The optimized process parameters for enzymatic hydrolysis of glu- tinous rice protein with neutral protease were： protein substrate concentration of 2%, enzyme dosage of 24 000 U/g protein （protein meter）, enzymatic hydrolysis temperature of 55 ℃, initial pH of 8.0, and enzymatic hydrolysis duration of 0.5 h; under these conditions, the hydroxyl radical scavenging rate could reach 56. 05% ; protein substrate concentration, enzyme dosage, enzymatic hydrolysis temperature and initial pH had extremely significant effects on the hydroxyl radical scavenging rate. In addition, the activities of antioxidant peptides in glutinous rice hydrolysates were well maintained within a temperature range of 60 - 100℃. [Condusion] The study produced theoretical feasibility reference for the production of functional base powder by spray drying.

Gate-tunable high-performance broadband phototransistor array of two-dimensional PtSe_(2) on SOI

Two-dimensional(2D)layered materials have attracted extensive research interest in the field of high-performance photodetection due to their high carrier mobility,tunable bandgap,stability,other excellent properties.Herein,we propose a gate-tunable,high-performance,self-driving,wide detection range phototransistor based on a 2D PtSe_(2)on silicon-oninsulator(SOI).Benefiting from the strong built-in electric field of the PtSe_(2)/Si heterostructure,the phototransistor has a fast response time(rise/fall time)of 36.7/32.6μs.The PtSe_(2)/Si phototransistor exhibits excellent photodetection performance over a broad spectral range from ultraviolet to near-infrared,including a responsivity of 1.07 A/W and a specific detectivity of 6.60×10^(9)Jones under 808 nm illumination at zero gate voltage.The responsivity and specific detectivity of PtSe_(2)/Si phototransistor at 5 V gate voltage are increased to 13.85 A/W and 1.90×10^(10) Jones under 808 nm illumination.Furthermore,the fabricated PtSe_(2)/Si phototransistor array shows excellent uniformity,reproducibility,long-term stability in terms of photoresponse performance with negligible variation between pixel cells.The architecture of present PtSe_(2)/Si on SOI platform paves a new way of a general strategy to realize high-performance photodetectors by combining the advantages of both 2D materials and conventional semiconductors which is compatible with current Si-complementary metal oxide semiconductor(CMOS)process.

近红外量子点发光二极管用于模拟神经突触可塑性（英文）

为了提高近红外发光二极管的性能,我们利用聚3-己基噻吩(P3HT)空穴迁移率高和对近红外光没有吸收的特点,将其作为器件的空穴传输层.实验发现,P3HT改善了基于硅量子点的近红外发光二极管的空穴/电子传输不平衡的现象.进一步地,将聚[9,9-二(3'-(N,N-二甲胺基)丙基)-2,7-芴-交-2,7-(9,9-二辛基芴)](PFN)作为中间层修饰P3HT,近红外硅量子点发光二极管的性能得到了更大改善,其外量子效率和功率效率分别达到了3.4%和4.4%.性能改善后的近红外硅量子点发光二极管可以用于模拟神经突触的可塑性,如短时程可塑性和长时程可塑性.

High performance IEICO-4F/WSe_(2)heterojunction photodetector based on photoluminescence quenching behavior

Heterostructure is the basic building block for functional optoelectronic devices.Heterostructures consisting of two-dimensional(2D)transition metal dichalcogenides(TMDs)and organic semiconductors are currently attracting great interest for highperformance optoelectronics.However,how to design heterostructure for highly efficient optoelectronic devices remains a big challenge.Here we design high-performance organic semiconductor/WSe_(2)heterostructure photodetectors by tailoring the charge transfer effect between 2,2ʹ-((2Z,2ʹZ)-(((4,4,9,9-tetrakis(4-hexylphenyl)-4,9-dihydros-indaceno[1,2-b:5,6-bʹ]dithiophene-2,7-diyl)bis(4-((2-ethylhexyl)oxy)thiophene-5,2-diyl))bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(IEICO-4F)organic semiconductors with various thicknesses and monolayer WSe_(2).With the increase of IEICO-4F layer thickness,the photoluminescence(PL)characteristics of WSe_(2)could be completely quenched due to the charge transfer from the lowest unoccupied molecular orbital(LUMO)level of IEICO-4F to the conduction band minimum(CBM)of WSe_(2).Benefiting from the exquisite charge transfer behavior,the IEICO-4F/WSe_(2)heterojunction photodetector with optimized 6.0-nm thick IEICO-4F shows high performance including the responsivity of 8.32 A/W and specific detectivity of 4.65×10^(11)Jones at incident light of 808 nm.This work demonstrates a simple approach based on PL characteristics to design high-performance IEICO-4F/WSe_(2)heterojunction,thus paving the way for the development of excellent optoelectronic devices based on organic/TMD heterostructures.

Reduced thermal boundary conductance in GaN-based electronic devices introduced by metal bonding layer

Achieving high interface thermal conductance is one of the biggest challenges in the nanoscale heat transport of GaN-based devices such as light emitting diodes(LEDs),and high electron mobility transistors(HEMTs).In this work,we experimentally measured thermal boundary conductance(TBC)at interfaces between GaN and the substrates with AuSn alloy as a commonly-used adhesive layer by time-domain thermoreflectance(TDTR).We find that the TBCs of GaN/Ti/AuSn/Ti/Si,GaN/Ti/AuSn/Ti/SiC,and GaN/Ti/AuSn/Ti/diamond,are 16.5,14.8,and 13.2 MW·m^(-2)·K^(-1)at room temperature,respectively.Our measured results show that the TBC of GaN/Ti/AuSn/Ti/SiC interface is inferior to the TBC of pristine GaN/SiC interface,due to the large mismatch of phonon modes between AuSn/Ti and substrates,shown as the difference of Debye temperature of two materials.Overall,we measured the TBC at interface between GaN and thermal conductive substrates,and provided a guideline for designing the interface between GaN and substrate at HEMT from a thermal management point of view.

Synthesis of Sn nanocluster@carbon dots for photodynamic therapy application

Recently,photodynamic therapy(PDT)has been extensively applied in clinical and coadjuvant treatment of various kinds of tumors.However,the photosensitizer(PS)of PDT still lack of high production of singlet oxygen(^(1)O_(2)),low cytotoxicity and high biocompatibility.Herein,we propose a facile method for establishing a new core-shell structured Sn nanocluster@carbon dots(CDs)PS.Firstly,Sn^(4+)@S-CDs complex is synthesized using the sulfur-doped CDs(S-CDs)and SnCl4 as raw materials,and subsequently the new PS(Sn nanocluster@CDs)is obtained after vaporization of Sn4+@S-CDs solution.Remarkably,the obtained Sn nanocluster@CDs show an enhanced fluorescence as well as a higher ^(1)O_(2) quantum yield(QY)than S-CDs.The high ^(1)O_(2) QY(58.3%)irradiated by the LED light(400-700 nm,40 mW/cm^(2)),induce the reduction of 4 T1 cancer cells viability by 25%.More intriguingly,no visible damage happens to healthy cells,with little impact on liver tissue due to renal excretion,both in vitro and in vivo experiments demonstrate that Sn nanocluster@CDs may become a promising PS,owning a high potential for application in PDT.

Erratum to:Improving near-infrared quantum-dot light-emitting diodes to mimic synaptic plasticity(vol 62,issue 10,page 1470,2019)

In the version of the article originally published in the volume 62,issue 10,2019 of Sci.China Mater,(page 1470-1478,https://doi.org/10.1007/s40843-019-9437-9),wrong images of Figs 3 and 4 were used.The corrected version appears below:the units of the x-axes in Fig.3h,the inset of Fig.4a,and Fig.4b,d should be h,s,s,and s,respectively.

From Solid Carbon Sources to Graphene

Chemical vapor deposition on metal substrates using gaseous hydrocarbon as carbon feedstock has proven to be a feasible way for synthesis of large-area and uniform graphene films. Meanwhile, rearrangement of amorphous carbon species extracted from solid carbon sources into crystalline graphene not only offers an alternative route for graphene growth but also provides a powerful tool to excavate the underlying mechanisms of graphene formation. In this review, we discuss the processes of extracting carbon species from various solid carbon sources to form gra- phene. We summarize the typical steps of solid carbon sources to graphene transition and evaluate the resultant graphene film quality with regard to electrical performance. Unveiling the detailed solid carbon to graphene transition process paves the way for a reproducible production of graphene with controlled layer number, defect type and density, toward the final end of graphene＇s commercial utilizations with low cost.

One-pot synthesis of CoO-ZnO/rGO supported on Ni foam for high-performance hybrid supercapacitor with greatly enhanced cycling stability

The high specific capacitance along with good cycling stability are crucial for practical applications of supercapacitors,which always demands high-performance and stable electrode materials.In this work,we report a series of ternary composites of CoO-ZnO with different fractions of reduced graphene oxide(rGO)synthesized by in-situ growth on nickel foam,named as CZG-1,2 and 3,respectively.This sort of binder-free electrodes presents excellent electrochemical properties as well as large capacitance due to their low electrical resistance and high oxygen vacancies.Particularly,the sample of CZG-2(CoO-ZnO/rGO 20 mg)in a nanoreticular structure shows the best electrochemical performance with a maximum specific capacitance of 1951.8 F/g(216.9 mAh/g)at a current intensity of 1 A/g.The CZG-2-based hybrid supercapacitor delivers a high energy density up to 45.9 Wh/kg at a high power density of 800 W/kg,and kept the capacitance retention of 90.1%over 5000 charge-discharge cycles.