Study on Spatial Distribution of OM, N, P in Surface Soil around Lake Chaohu

The concentration of total nitrogen (TN), total phosphorus (TP) and organic material (OM) at sixty grid division in Lake Chaohu basin around the lake was studied, in order to investigate their spatial distribution characteristics. The results showed that the average concentrations of TN, TP and OM were 1027 mg/kg, 483 mg/kg, 1.95%, and their concentrations ranged from 253 mg/kg to 2273 mg/kg, 223 mg/kg to 1173 mg/kg and 0.291% to 5.48%, respectively. The high concentration areas were located at the basins of Tuogao river and Zhao river while the low concentration areas were located at basins of Pai river, Nanfei river and Dianpu river. The concentrations of TN and OM were higher in East part than in West part. The spatial distribution of TN, TP and OM concentrations of the surface soil showed inconsistent with those of the water quality of the inflow rivers and the lake and the TN and TP of lake sediment studied.

信息技术支持我国课堂教学变革的发展阶段和内在逻辑

自21世纪以来,我国教育信息化快速发展,各类信息技术不断应用于课堂教学之中。这些信息技术是否引发了常规课堂教学深层次的变革?本文通过分析我国中小学课堂教学三类常规数字媒体所支持的教学理念与方式,揭示深层次教学方式变革的发展阶段,并进一步厘清教学变革发生、发展的内在逻辑。按照变革的发生顺序,信息技术支持的课堂教学变革可分为多媒体技术支持下的教学认知方式变革、交互技术支持下的教学行为方式变革和智能技术支持下的教学组织方式变革。这三场课堂教学变革不是偶然发生的,而是在一定的内在逻辑指导下在继承与发展的规律中有序地依次发生的。其中的内在逻辑主要表现为:(1)信息技术支持课堂教学变革的内驱力是对教与学的时代追求;(2)信息技术支持课堂教学变革的主要对象是学生和学习;(3)信息技术支持课堂教学变革的实践方式主要是“上层引领—底层推动”模式。

Integration of flexible,recyclable,and transient gelatin hydrogels toward multifunctional electronics

Facing the challenges posed by exponentially increasing e-waste,the development of recyclable and tran-sient electronics has paved the way to an environmentally-friendly progression strategy,where electron-ics can disintegrate and/or degrade into eco-friendly end products in a controlled way.Natural polymers possess cost and energy efficiency,easy modification,and fast degradation,all of which are ideal prop-erties for transient electronics.Gelatin is especially attractive due to its unique thermoreversible gelation processes,yet its huge potential as a multifunctional electronic material has not been well-researched due to its limited mechanical strength and low conductivity.Herein,we explored versatile applications of gelatin-based hydrogels through the assistance of multifunctional additives like carbon nanotubes to enhance their electromechanical performances.The optimized gelatin hydrogel displays not only a high conductivity of 0.93 S/m,electromagnetic shielding effectiveness of 39.6 dB,and tensile stress tolerance of 263 kPa,but also shows a negative permittivity phenomenon,which may find versatile applications in novel electronics.As a proof of concept,hydrogels were assembled as wearable sensors to sensitively de-tect static and dynamic pressures and strains generated by solids,liquids,and airflow,as well as diverse body movements.Furthermore,the recyclability,biocompatibility,and degradability of gelatin-based hy-drogels were well studied and analyzed.This work outlines a facile method to design multifunctional transient materials for wearable,sustainable,and eco-friendly electronics.

Energy flexibility characteristics of centralized hot water system in university dormitories

The large-scale application of renewable energy is an important strategy to achieve the goal of carbon neutrality in the building sector.Energy flexibility is essential for ensuring balance between energy demand and supply when targeting the maximum penetration rate of renewable energy during the operation of regional integrated energy systems.Revealing the energy flexibility characteristics of centralized hot water systems,which are an important source of such flexibility,is of great significance to the optimal operation of regional integrated energy systems.Hence,in this study,based on the annual real-time monitoring data,the energy flexibility of the centralized hot water system in university dormitories is evaluated from the perspective of available storage capacity(C_(ADR)),recovery time(t_(recovery)),and storage efficiency(η_(ADR)),by the data-driven simulation method.The factors influencing the energy flexibility of the centralized hot water system are also analyzed.Available storage capacity has a strong positive correlation with daily water consumption and a strong negative correlation with daily mean outdoor temperature.These associations indicate that increased water use on the energy flexibility of the centralized hot water system is conducive to optimal dispatching.In contrast,higher outdoor temperature is unfavorable.The hourly mean value of the available storage capacity in spring and winter is found to be around 80 kWh in the daytime,and about twice that in summer and autumn.Recovery time is evenly distributed throughout the year,while t_(recovery)/C_(ADR)in spring and winter is about half that in summer.The storage efficiency was significantly higher in spring,summer,and winter than in autumn.The hourly mean storage efficiency was found to be about 40%in the daytime.The benefits of activating energy flexibility in spring and winter are the best,because these two seasons have higher available storage capacity and storage efficiency,while the benefit of activating energy flexibility is the highest at 6:00 a.m.,and very low from midnight to 3:00 a.m.

Nanomaterial Labels in Lateral Flow Immunoassays for Point-of-Care-Testing

Lateral flow immunoassays(LFIAs) have been developed rapidly in recent years and used in a wide range of application at point-of-care-testing(POCT),where small biomolecules can be conveniently examined on a test strip.Compared with other biochemical detection methods such as ELISA(enzyme linked immunosorbent assay) or mass spectrometry method,LFIAs have the advantages of low cost,easy operation and short time-consuming.However,it suffers from low sensitivity since conventional LFIA can only realize qualitative detection based on colorimetric signals.With the increasing demand for more accurate and sensitive determination,novel nanomaterials have been used as labels in LFIAs due to their unique advantages in physical and chemical properties.Colloidal gold,fluorescent nano particles,SERSactive nanomaterials,magnetic nanoparticles and carbon nanomaterials are utilized in LFIAs to produce different kinds of signals for quantitative or semi-quantitative detection.This review paper first gives a description of the LFIA principles,and then focuses on the state-of-the-art nanomaterial labelling technology in LFIAs.At last,the conclusion and outlook are given to inspire exploration of more advanced nanomaterials for the development of future LFIAs.