Outstanding Humidity Chemiresistors Based on Imine-Linked Covalent Organic Framework Films for Human Respiration Monitoring

Human metabolite moisture detection is important in health monitoring and non-invasive diagnosis.However,ultra-sensitive quantitative extraction of respiration information in real-time remains a great challenge.Herein,chemiresistors based on imine-linked covalent organic framework(COF)films with dual-active sites are fabricated to address this issue,which demonstrates an amplified humidity-sensing signal performance.By regulation of monomers and functional groups,these COF films can be pre-engineered to achieve high response,wide detection range,fast response,and recovery time.Under the condition of relative humidity ranging from 13 to 98%,the COFTAPB-DHTA film-based humidity sensor exhibits outstanding humidity sensing perfor-mance with an expanded response value of 390 times.Furthermore,the response values of the COF film-based sensor are highly linear to the relative humidity in the range below 60%,reflecting a quantitative sensing mechanism at the molecular level.Based on the dual-site adsorption of the(-C=N-)and(C-N)stretching vibrations,the revers-ible tautomerism induced by hydrogen bonding with water molecules is demonstrated to be the main intrinsic mechanism for this effective humidity detection.In addition,the synthesized COF films can be further exploited to effectively detect human nasal and oral breathing as well as fabric permeability,which will inspire novel designs for effective humidity-detection devices.

Controllable Synthesis of Fluorescent Carbon Dots and Their Detection Application as Nanoprobes

Carbon dots(CDs), as a new member of carbon nanomaterial family, have aroused great interest since their discovery in 2004. Because of their outstanding water solubility, high sensitivity and selectivity to target analytes, low toxicity, favorable biocompatibility, and excellent photostability, researchers from diverse disciplines have come together to further develop the fundamental properties of CDs. Many methods for the production of CDs have been reported, therein, hydrothermal and solvothermal technology needs simple equipments, and microwave synthesis needs less reaction time, hence these methods become current common synthesis methods, in which many precursors have been applied to produce CDs. Due to their excellent fluorescence, CDs have made impressive strides in sensitivity and selectivity to a diverse array of salt ions,organic/biological molecules and target gases. The development of CDs as nanoprobes is still in its infancy, but continued progress may lead to their integration into environmental and biological applications. Hydrothermal,solvothermal, and microwave synthesis of fluorescent carbon dots and their detection applications as nanoprobes in salt ions, organic/biological molecules, and target gases will be reviewed.

Highly Enhanced Visible-Light-Driven Photoelectrochemical Performance of ZnO-Modified In_2S_3 Nanosheet Arrays by Atomic Layer Deposition

Photoanodes based on In_2S_3/ZnO heterojunction nanosheet arrays(NSAs) have been fabricated by atomic layer deposition of ZnO over In_2S_3 NSAs, which were in situ grown on fluorine-doped tin oxide glasses via a facile solvothermal process. The as-prepared photoanodes show dramatically enhanced performance for photoelectrochemical(PEC) water splitting, compared to single semiconductor counterparts. The optical and PEC properties of In_2S_3/ZnO NSAs have been optimized by modulating the thickness of the Zn O overlayer. After pairing with ZnO, the NSAs exhibit a broadened absorption range and an increased light absorptance over a wide wavelength region of 250–850 nm. The optimized sample of In_2S_3/ZnO-50 NSAs shows a photocurrent density of 1.642 m A cm^(-2)(1.5 V vs. RHE) and an incident photonto-current efficiency of 27.64% at 380 nm(1.23 V vs.RHE), which are 70 and 116 times higher than those of the pristine In_2S_3 NSAs, respectively. A detailed energy band edge analysis reveals the type-II band alignment of the In_2S_3/ZnO heterojunction, which enables efficient separation and collection of photogenerated carriers,especially with the assistance of positive bias potential, and then results in the significantly increased PEC activity.

A Novel Artificial Neuron-Like Gas Sensor Constructed from CuS Quantum Dots/Bi2S3 Nanosheets

Real-time rapid detection of toxic gases at room temperature is particularly important for public health and environmental monitoring.Gas sensors based on conventional bulk materials often suffer from their poor surface-sensitive sites,leading to a very low gas adsorption ability.Moreover,the charge transportation efficiency is usually inhibited by the low defect density of surface-sensitive area than that in the interior.In this work,a gas sensing structure model based on CuS quantum dots/Bi_(2)S_(3) nanosheets(CuS QDs/Bi_(2)S_(3) NSs)inspired by artificial neuron network is constructed.Simulation analysis by density functional calculation revealed that CuS QDs and Bi_(2)S_(3) NSs can be used as the main adsorption sites and charge transport pathways,respectively.Thus,the high-sensitivity sensing of NO_(2) can be realized by designing the artificial neuron-like sensor.The experimental results showed that the CuS QDs with a size of about 8 nm are highly adsorbable,which can enhance the NO_(2) sensitivity due to the rich sensitive sites and quantum size effect.The Bi_(2)S_(3) NSs can be used as a charge transfer network channel to achieve efficient charge collection and transmission.The neuron-like sensor that simulates biological smell shows a significantly enhanced response value(3.4),excellent responsiveness(18 s)and recovery rate(338 s),low theoretical detection limit of 78 ppb,and excellent selectivity for NO_(2).Furthermore,the developed wearable device can also realize the visual detection of NO2 through real-time signal changes.

Hexagonally ordered microbowl arrays decorated with ultrathin CuInS_(2) nanosheets for enhanced photoelectrochemical performance

This paper demonstrates the design and fabrication of three-dimensional(3 D) hexagonally ordered microbowl arrays(MBAs) decorated with Cu In S2 nanosheets for enhanced photoelectrochemical(PEC) performance. The 3 D MBAs are fabricated by a micro-fabrication technique. The ultrathin CuInS2 nanosheets are grown on the 3 D electrodes by solvothermal transformation of Cu film. The photocurrent density of 3 D photocathode(CuInS2@MBAs) is about two times higher than that of the planar counterpart(CuInS2@Planar). The improved PEC performance can be ascribed to the elevated light trapping ability and the increased surface area for loading photocatalysts. In addition, CdS quantum dots as cocatalysts are modified onto the Cu In S2 nanosheets to further enhance the PEC activity because the formed p-n heterojunction can accelerate the separation of photogenerated carriers. As a result, the 3 D photocathode of CuInS2/CdS@MBAs shows an optimal incident photon to current efficiency of 10% at the wavelength of400 nm. It is believed that this work can be generalized to design other hierarchical 3 D photoelectrodes for improved solar water splitting.

A non-invasive smart scaffold for bone repair and monitoring

Existing strategies for bone defect repair are difficult to monitor.Smart scaffold materials that can quantify the efficiency of new bone formation are important for bone regeneration and monitoring.Carbon nanotubes(CNT)have promising bioactivity and electrical conductivity.In this study,a noninvasive and intelligent monitoring scaffold was prepared for bone regeneration and monitoring by integrating carboxylated CNT into chemically cross-linked carboxymethyl chitosan hydrogel.CNT scaffold(0.5%w/v)demonstrated improved mechanical properties with good biocompatibility and electrochemical responsiveness.Cyclic voltammetry and electrochemical impedance spectroscopy of CNT scaffold responded sensitively to seed cell differentiation degree in both cellular and animal levels.Interestingly,the CNT scaffold could make up the easy deactivation shortfall of bone morphogenetic protein 2 by sustainably enhancing stem cell osteogenic differentiation and new bone tissue formation through CNT roles.This research provides new ideas for the development of noninvasive and electrochemically responsive bioactive scaffolds,marking an important step in the development of intelligent tissue engineering.

儿童心理理论发生与发展:跨文化的视角

宏观的文化背景会塑造儿童心理理论的发生与发展进程.通过发现不同文化下儿童发展的相似性和差异性规律,有助于将儿童心理理论发展普遍规律和特定文化背景下的发展现象区分开来.文献回顾表明,儿童心理理论发生与发展既有文化普遍性,又表现出文化特异性.在这种背景下,研究者开始聚焦于儿童心理理论文化特异性的相关因素.当前,研究者主要从亲子交流、家庭教养方式、学校教学模式及执行功能促进心理理论发展的内在机制等方面的跨文化差异,来阐释儿童心理理论发生发展规律的文化特异性.通过整合现有关于儿童心理理论发展跨文化差异的主要研究文献,以及尚未解决的研究问题,本文提出一个儿童心理理论发生与发展的文化模型.最后,文章对未来研究需要深入探讨的关键问题进行了展望.

二维过渡金属硫族化合物纳米异质结气体传感器研究进展

二维过渡金属硫族化合物(2D TMDs)在气体传感方向的应用中具有显著的"先天"优势,表现出如灵敏度高、响应速度快、能耗低以及能在室温下工作等诸多优点.相对单一的2D TMDs而言,基于2D TMDs纳米异质结的气体传感器展现出更加优越的气体传感性能.本文将系统总结2D TMDs纳米异质结气体传感器的研究进展,尤其是2D TMDs与金属氧化物、金属硫化物、碳基纳米材料以及量子点之间形成的纳米异质结设计、构效关系以及传感机理等关键科学问题.传感材料和传感机制上的创新对提升传感性能并拓展传感功能具有重要的科学意义.通过对纳米异质结气敏机理的深入探究,有望实现纳米异质结结构的人为设计和可控制备,提高室温下对目标气体的高灵敏选择性识别和检测.在纳米异质结的结构设计上,以TMDs材料为导电主体,在其表面生长各种纳米结构,通过对纳米异质结表面酸碱性、功函数、气体分子极性以及纳米异质结与气体分子之间的氧化还原反应性质进行调控,来构筑基于TMDs的纳米异质结.此外,控制负载在二维TMDs上纳米颗粒尺寸小于两倍电子耗尽层厚度,充分发挥纳米颗粒量子限域效应,以纳米颗粒充当传感的"天线分子"或"探针分子",实现对目标气体分子的高灵敏选择性识别和检测.

Jiao Shao: A forerunner of physiological psychology and comparative psychology in China

Jiao Shao (邵郊,1923-2017)(Fig. 1), who was an expert in physiological psychology and comparative psychology in China, made important contributions to the development of physiological psychology and comparative psychology, scientific research and personnel training (The obituary of Jiao Shao, 2017). He was a member of the Second Discipline Review Group of the State Council (Pedagogy), the director of the third and fifth sessions of Chinese Psychological Society (CPS), the chairman of the Professional Committee on Physiological Psychology of the CPS (1984-1988), an editorial advisory board member of the Encyclopedia of China Publishing House (First Edition), an editorial board member of Acta Psychologica Sinica (1979-1991), and he was honored as a fellow of the CPS (2007).

Variations in the oxytocin receptor gene and prosocial behavior:moderating effects of situational factors

Humans are the most prosocial primate species and they often exhibit high levels of prosocial behavior toward genetically unrelated individuals.Traditional evolutionary theories are not sufficient to explain the individual differences and mechanisms related to prosociality.In this study,we focused on the gene–situation interaction in prosocial behaviors,and the patterns of genotype variance related to cooperation and comforting in different situations.We explored the interaction between the oxytocin receptor(OXTR)gene and situations,and the genotype variance under low and high prosociality situations between outgroup and ingroup recipients in a sample of 422 Chinese males.Prosociality was tested by measuring the prosocial tendencies,and prosocial behaviors were tested in cooperation and comforting tasks.OXTR single nucleotide polymorphisms(SNPs)were genotyped using polymerase chain reaction–restriction fragment length polymorphism analysis.The results suggested that the relationship between OXTR SNPs(specifically rs13316193,rs1042778 and rs237887)and prosocial behavior varied across different situations,and that the associations were moderated by the recipient’s identity and the prosocial cost.Our findings indicate the action of a moderating mechanism between the OXTR gene and prosocial behaviors according to situational factors.

A novel channel-wall engineering strategy for two-dimensional cationic covalent organic frameworks:Microwave-assisted anion exchange and enhanced carbon dioxide capture

A novel channel-wall engineering strategy of the porous materials cationic covalent organic frameworks(COFs)is established based on rapid microwave-assisted anion exchange reaction and utilized to prepare a set of new COFs.Due to the interaction between the carbon dioxide(C02)and the acetate anion,the resulting SJTU-COF-AcO shows greatly enhanced carbon dioxide capacity up to 1.7 times of the pristine COF.The effect of the counteranions to CO2 capacity in the cationic COFs is investigated for the first time,which demonstrates that our channel-wall engineering strategy is a promising way to tailor the property of COFs for high CO2 capacity.