阴极射线管锥玻璃真空碳热还原除铅机理研究

阴极射线管(cathode ray tube,CRT)玻璃附加值极低,毒性浸出实验表明CRT玻璃为危险废物,是当前我国电子垃圾处理处置中首要的必须解决的难题。废弃CRT玻璃安全处理处置的关键在于其含铅锥玻璃的处理处置。文章从锥玻璃的组成出发,探讨真空碳热还原除铅的可能性及可行性,计算表明真空碳热还原除铅完全可能,实验结果表明900℃,10 Pa下反应4 h铅的去除率可达93.53%,残余物中铅的质量分数仅为0.9%。该法为解决废弃危险电子垃圾CRT玻璃问题提供了新的思路,具有较强的应用价值。

Mg-doped SrTaO_(2)N as a visible-light-driven H_(2)-evolution photocatalyst for accelerated Z-scheme overall water splitting

Perovskite SrTaO_(2)N is one of the most promising narrow-bandgap photocatalysts for Z-scheme overall water splitting.However,the formation of defect states during thermal nitridation severely hinders the separation of charges,resulting in poor photocatalytic activity.In the present study,we successfully synthesize SrTaO_(2)N photocatalyst with low density of defect states,uniform morphology and particle size by flux-assisted one-pot nitridation combined with Mg doping.Some important parameters,such as the size of unit cell,the content of nitrogen,and microstructure,prove the successful doping of Mg.The defect-related carrier recombination has been significantly reduced by Mg doping,which effectively promotes the charge separation.Moreover,Mg doping induces a change of the band edge,which makes proton reduction have a stronger driving force.After modifying with the core/shell-structured Pt/Cr_(2)O_(3)cocatalyst,the H_(2)evolution activity of the optimized SrTaO_(2)N:Mg is 10 times that of the undoped SrTaO_(2)N,with an impressive apparent quantum yield of 1.51%at 420 nm.By coupling with Au-FeCoO_(x)modified BiVO_(4)as an O_(2)-evolution photocatalyst and[Fe(CN)_(6)]_(3)−/[Fe(CN)_(6)]_(4)−as the redox couple,a redox-based Z-scheme overall water splitting system is successfully constructed with an apparent quantum yield of 1.36%at 420 nm.This work provides an alternative way to prepare oxynitride semiconductors with reduced defects to promote the conversion of solar energy.

ZNT1 Involves Cuproptosis through Regulating MTF1-conduced Expression of MT1X under Copper Overload

Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o rganisms,plants and animals through direct or indirect exposure.However,the current understanding of the toxicity of copper is rather limited.Copper overload can perturb intracellular homeostasis and induce oxidative stress and e ven cell death.Recently,cuproptosis has been identified as a copper-dependent form of cell death induced by o xidative stress in mitochondria.We uncover here that zinc transporter 1(ZNT1)is an important regulator involved in cuproptosis.Firstly,we established the copper overload-induced cell death model with the overexpression of copper importer SLC31A1 in HeLa cells.Using this model,we conducted unbiased genome-wide CRISPR-Cas9 screens in cells treated with copper.Our results revealed a significant enrichment of ZNT1 gene in both library A and library B plasmids.Knocking out of ZNT1 in HeLa cells notably prevented cuproptosis.Subsequent knockout of metal transcription factor 1(MTF1)in ZNT1-deficient cells nearly abolished their ability to resist copper-induced cell death.However,overexpression of metallothionein 1X(MT1X)in the double-knockout cells could p artially restored the resistance to cuproptosis by loss of MTF1.Mechanistically,knockout of ZNT1 could promote MT1X expression by activating MTF1.As a consequence,the interaction between MT1X and copper was e nhanced,reducing the flow of copper into mitochondria and eliminating mitochondria damage.Taken together,this study reveals the important role of ZNT1 in cuproptosis and shows MTF1-MT1X axis mediated resistance to c uproptosis.Moreover,our study will help to understand the regulatory mechanism of cellular and systemic copper homeostasis under copper overload,and present insights into novel treatments for damages caused by both genetic copper overload diseases and environmental copper contamination.

C3N4 modified with single layer ZIF67 nanoparticles for efficient photocatalytic degradation of organic pollutants under visible light

Uniformly distributed single layer of ZIF67-derived C3N4(ZIF67-C3N4)was synthesized and applied to the photocatalytic degradation of methylene blue(MB)under visible light.Results indicated that the obtained ZIF67-C3N4 has a maximum specific surface area of 541.392 m^2/g,which is much larger than that of raw C3N4 of 97.291 m^2/g.The investigation of C3N4 amount involved in ZIF67-C3N4 on the photoactivity revealed that 2.57 g ZIF67 with 0.3 g C3N4,which named ZIF67-C3N4(0.3)exhibited superior photocatalytic activities.More than 90%of MB at 10 mg/L was degraded within 70 min with the addition of 0.01 g ZIF67-C3N4(0.3),while this time required for raw C3N4 was over 140 min.The effects of pH of solution,initial concentration of MB and dosage of C3N4 in ZIF67-C3N4 composites on the photocatalytic efficiency for MB degradation were also evaluated.Quenching experiments indicated that the photo-induced holes(h^+)and superoxide radicals(O2-·)were mainly responsible for MB degradation.It is anticipated that the insertion of ZIF67 nanoparticles not only increases the adsorption capacity of C3N4 but also promotes the generation and migration of the photo-induced active species.

Driving Factors of Coordinated Development in Chinese Border Cities:A Case Study of Lincang City in Southwest China

In the context of the“Belt and Road Initiative”,the sustainable development of border cities is paramount for facilitating intergovernmental exchanges.Using the system dynamics approach,we integrated border policy factors to create the Border City Coordinated Development(BCCD-SD)model,encompassing three dimensions:Economic,Social,and Resource-Environment.Furthermore,a comprehensive evaluation indicator,the City Coordinated Development Index(CCDI),was devised.Using Lincang City in Southwest China as a case study,this article examines the trends in city development under three scenarios:Inertial Development,Rapid Development,and Green Development.The research findings demonstrate that the model adeptly captures trends in the city coordinated development indicators.Among the three scenarios,the rapid development scenario stands out,yielding the most favorable economic indicators,superior public infrastructure,and the highest employed population.However,the rapid development path,which is heavily focused on economic growth,intensifies resource and environmental pressures,giving rise to sustainability challenges.In contrast,although the green development scenario trails slightly in economic performance compared to rapid development,it fosters a larger urban population and transition of the employed population into citizens while excelling in resource and environmental aspects.Overall,the CCDI attains its highest score under the green development scenario,surpassing those of rapid and inertia development,signifying superior city development coordination along the green path.This scenario effectively combines economic growth,social progress,and resource-environment protection.This study also emphasizes the pivotal role of ports in the coordinated development of border cities and underscores the necessity of expediting the transition from a“gateway”economy to a“port+”economy.One objective of this article is to encourage border cities to serve as more effective windows to the outside world,promote regional coordination,and achieve high-quality development.

碱性果胶酶的应用进展

碱性果胶酶分解复杂的果胶成小分子如半乳糖醛酸。碱性果胶酶在茶和咖啡发酵、纺织和植物纤维加工、油提取、含果胶工业废水处理等领域具有广泛应用。最近有些有关碱性果胶酶应用于造纸、植物病毒纯化、诱导植物抗病、家禽饲料、洗涤剂等领域的报道。综述了碱性果胶酶在各个领域中的应用。

Spatio-temporal Characteristics of the Extreme Climate Events and Their Potential Effects on Crop Yield in Ethiopia

Extreme climate events exhibit an increasing spatio-temporal trend globally, and the increasing intensity and frequency may have severe impacts on the human society and natural ecosystems. This study analyzed the extreme temperature and precipitation variability from 1956 to 2016, and evaluated their potential effects on crop yield in Ethiopia. Relative extreme temperature indices exhibited a decreasing trend with low-temperature events, but a significantly upward trend with extreme high temperature events. The frequency of annual warm nights increased to a greater degree than that of cold days. The total annual wet-day precipitation decreased significantly at a rate of-46 mm/decade. Further, the succession of dry days gradually increased by 5.6 day/decade, while an opposite trend of wet days was found with a decline of 1.4 day/decade. The correlation between annual precipitation and crop production was 0.422, indicating that extreme precipitation indices may have higher explanatory power than extreme temperature indices in the crop yield variations. Moreover, the extreme climate changes have induced significant adverse impacts on crops yield particularly in Ethiopia where no proper adaptation measures have been implemented.

Coupling Conservation and Livelihoods for Sustainable Management of Protected Areas in East Africa

Strengthening research efforts to understand the combined impacts of conservation and livelihoods in protected areas（PAs） will increase the collective contribution that PAs can make towards meeting global goals for sustainable development in the next decade. As an example of such efforts, in 2014 the Chinese Academy of Sciences（CAS）, the Kenya Wildlife Service（KWS） and the United Nations Environment Programme（UN Environment） jointly initiated the ＂Sustainable Management of Protected Areas in East Africa＂ project. This paper provides a brief overview of the project＇s research background, goals and research tasks. The study is based on a look at the PA management system in East Africa and a review of the literature on the impact of PAs in the region. Results show that East African nations have expanded the coverage of PAs and established a complex set of PA management systems over the past century. The mandate for PAs in East African nations has changed recently from protecting biodiversity to alleviating poverty and supporting livelihoods. However, a combination of human activities and ecological processes inside and outside of PAs may not only impact biodiversity and ecosystem function over the long term, but also pose a threat to the capacity of PAs to maintain livelihoods and alleviate poverty in the local communities around them. The state of existing research in the field suggests there is an enormous need for additional research, the purpose of which is to help PA managers and policy-makers in East Africa understand how to achieve win-win outcomes for both ecosystems and human well-being. Against this background, the CAS-KWS-UN Environment joint research project aims to understand the dynamic interactions between ecosystems and human well-being around PAs in East Africa and identify good practices for PA management to reconcile conservation targets with the livelihood demands of local communities. It is intended that this research be shared with interested parties throughout the developing world. Significant progress has been made in the implementation of the project, in terms of data collection, exchanges of researchers, and the completion of case studies. In the coming year, success stories and examples of failures of PA management in the region will be systematically summarized and shared among scientists, managers and decision makers worldwide. Given its blueprint for building a ＂Beautiful China＂, China can both supplement and benefit from East African knowledge and experience of PA management. This joint research effort promotes Sino-African cooperation on PA research and management.

Regional Differentiation and Classification for Carrying Constraints on the Resources and Environment of China

Research on the relationship between national resource constraint-region types and environmental carrying capacity is essential for the continued development of Chinese industrialization and urbanization.Thus,utilizing a series of key indexes including the per-capita potential of available land resources,the per-capita potential of available water resources,the degree of environmental stress,and the degree of ecological restriction,a step-by-step,integrated measuring method is presented here to understand the constrained carrying elements of water and land resources as well as environment and ecology.Spatial differences are analyzed and area types classified at the county level across China.Results reveal that：（1）Almost 90%of China is strongly constrained by both resources and the environment,while nearly 50%of national territory is strongly constrained by two elements,especially in areas of intensive population and industry to the east of the Helan-Longmen Mountain line;（2）Densely populated areas of eastern and central China,as well as on the Tibetan Plateau,are strongly constrained by a shortage of land resources,while North China,the northwest,northeast,the Sichuan basin,and some southern cities are experiencing strong constraints because of water shortages.In contrast,the North China plain,the Yangtze River delta,northern Jiangsu,Sichuan province,Chongqing municipality,Guizhou and Guangxi provinces,the northeast plain,and the northern Loess Plateau are constrained by high levels of environmental stress.Areas of China that are strongly ecologically constrained tend to be concentrated to the southwest of the Tianshan-Dabie Mountain line,as well as in the northeast on the Loess Plateau,in the Alashan of Inner Mongolia,in northeast China,and in the northern Jiangsu coastal area;（3）Constraints on national resources and environmental carrying capacity are diverse and cross-cut China,meanwhile,multi-element spatial distribution does reveal a degree of relative centralization.With the exception of the Tibetan Plateau which is resources-ecological constraint,other areas subject to cross constraints are mainly concentrated to the east of the Helan-Longmen Mountain line.

Understanding Agriculture Production and Food Security in Ethiopia from the Perspective of China

Food security and sustainable agricultural development are the hot issues of scientific research, especially after the population affected by hunger surprisingly increased in 2016. Long-lasting and recurrent famines caused by natural disasters and wars have afflicted Ethiopia. Unlike Ethiopia, which is still struggling to achieve food self-sufficiency, China managed to quickly become food self-sufficient at a rapid speed, despite the fact that it also faced the same challenges of famine over the last century. In the backdrop of differing environmental and socio-political challenges the two countries face, comparing the similarities and differences between the two countries will yield important lessons and insights for Ethiopia to follow to achieve food self-sufficiency. Here, the progress towards food security in Ethiopia and China is presented to quantitatively compare the gap of agricultural production between both countries. We found that food production in Ethiopia is heavily constrained by drought, soil degradation, climate change, out-dated agricultural production technologies, and poverty. According to these challenges, we examined corresponding responses in China to propose solutions for achieving food self-sufficiency in Ethiopia, given the realities of its unique national situation.