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Worldwide, the harmful ion contamination of water has become a serious problem because of unregulated industry, energy production, and mining, which greatly increase the concentration of pollutants in water. The novel membranes through adsorbent self-assembly, such as protein amyloids, were explored for wastewater treatment. Herein, we report amyloid fibril (AF)-embedded bacterial cellulose nanohybrid membrane for efficient removal of heavy metal from industrial effluent. AFs are synthesized by heat treatment using bovine serum albumin and embedded with bacterial cellulose nanomembrane (BCN). The AF-embedded BCN (AF/BCN) was characterized using microscopy and spectroscopic methods. In addition, the well-ordered multi-layered AF/BCN filtration assembly was fabricated in the commercial cartridge and validated for the removal of heavy metals (Pb2+ and Hg2+) from wastewater and treatment of industrial wastewater sample containing heavy metals. Our multi-layered filtration assembly removed Hg2+ and Pb2+ with efficiency of 95 and 78.34%, respectively. A computational study using molecular docking has also been performed for the identification of metal entrapment sites. Moreover, our AF/BCN filtration assembly showed high regeneration capacity up to four cycles. The isotherm model also revealed a strong fit and good adsorption behaviour. This makes potential filtration assembly for low-cost, high-efficiency for the removal of heavy metal from wastewater. HIGHLIGHTS Computational approaches methods for the study of bovine serum albumin.; Synthesis of amyloid fibril, amyloid-embedded bacterial cellulose nanomembrane (BCN), and fabrication of amyloid-embedded BCN filtration assembly.; Heavy metal removal analysis from industrial wastewater.;

در این پژوهش حذف آلاینده‌های آلی از آب تولید شده از مخزن گازی پس از جداسازی مواد روغنی مورد بررسی قرار گرفته است، به‌نحوی‌که بتوان COD آن را از مقداری حدود mg/L 9500 به محدوده مجاز آب کشاورزی رساند. در ابتدا با توجه به اینکه هدایت الکتریکی پساب خیلی بالا و در حد µS/cm 6300 است از روش تبخیر جهت کاهش آن استفاده شد که طی این فرآیند هدایت الکتریکی و COD آن به‌ترتیب به µS/cm 1100 و mg/L 750 تقلیل پیدا کرد. با توجه به رسیدن COD پساب به کم‌تر از mg/L 1000 در ادامه از روش فتوالکتروکاتالیست برای تصفیه محصول حاصل از فرآیند تبخیر استفاده شد. در روش فتوالکتروکاتالیست از نانومواد نیمه‌ هادی بور کربن نیترید (BCN) به‌عنوان فتوکاتالیست در میکروراکتور نوع سیم پیچی با نسبت سطح به حجم بالا در حدود 3 m2/m 3000 استفاده شد که همین امر باعث اکسیداسیون سریع مواد آلی می‌شود. پس از ساختن میکروراکتور، تأثیر پارامترهای مختلف بر میزان حذف COD مورد بررسی قرار گرفت که مشخص شد بیشترین میزان حذف COD در 3=pH، اختلاف پتانسیل V 20 و هدایت الکتریکی µS/cm 2500 به‌دست می‌آید (80%) که طی آن COD به mg/L 150 کاهش یافته که مناسب برای آبیاری و کشاورزی است.

BCN materials with varied structures are attracting attention for promising diverse applications. BCN materials are recognized for adaptable electrical properties, outstanding mechanical behavior, exceptional chemical inertness, and high thermal stability, which make them advantageous for corresponding applications in harsh environments. In this article, we thoroughly summarize BCN material theory, growth, properties, and applications. Properties of BCN thin films depend on the composition and growth technique, which facilitates in developing BCN films prevailing between insulating BN and semimetallic graphite. Regarding this, the effects of synthesis parameters on various BCN properties are examined. Dry and wet etching, which are imperative for device processing, are explored. Prompted by the success of graphene, graphene-analogous BCN nanomaterials are being researched intensively due to their unique chemical and physical properties. This article highlights BCN nanomaterials, their synthesis in different dimensions, and properties with prospective applications. We focus on their energy applications in supercapacitors, batteries, oxygen and hydrogen evolution reaction, water purification, and CO2 adsorption along with other biosensing applications. Performance of BCN nanomaterials is discussed and compared with the prevailing benchmark materials to present an evolutionary perspective of BCN nanomaterial progress. Finally, unresolved issues are highlighted, and future development opportunities are identified.

O objetivo deste trabalho é elaborar o balanço patrimonial de países com base nos cenários de mudanças climáticas e de aquecimento global apontados pelo Intergovernamental Panel on Climate Change (IPCC), da Organização das Nações Unidas (ONU). O estudo leva em consideração o estoque de recursos florestais e o saldo residual entre as emissões e capturas de carbono ou Greenhouse gas (GHG) estimadas para cada país, em 2020 e em 2050, de acordo com os relatórios Special Report on Emission Scenarios (SRES) A1B1 e A2B2. A pesquisa foi conduzida de forma multidisciplinar, envolvendo conceitos das áreas de biologia das mudanças climáticas, de energia, de geociência, de economia e da contabilidade. Esta última que foi utilizada para delimitar o objeto da pesquisa e servir de método, por meio da técnica Inquired Balance Sheet, para mensuração e classificação dos ativos, dos passivos e dos patrimônios líquidos ambientais. Selecionou-se uma amostra de sete países representantes do BRIC (Brasil, Rússia, Índia e China) e de países desenvolvidos da América, Europa e Ásia (EUA, Alemanha e Japão). Os balanços contábeis de cada país foram avaliados em unidades equivalentes de produto interno bruto (PIB), ajustados pelo consumo de energia per capita em toneladas equivalente de petróleo (TEP) e em mega toneladas de carbono (MtonC), precificadas pelo custo (US$) de captura de carbono sugeridos pela ONU. Os resultados da pesquisa mostram que os países desenvolvidos estão consumindo recursos de outras nações e de gerações futuras e, apesar de Brasil e Rússia apresentarem superávits ambientais, o balanço consolidado do planeta no cenário de 2050 aponta para uma situação deficitária ou falimentar, com "passivo a descoberto" ou patrimônio líquido negativo equivalente a US$ 2,3 mil anuais para cada um dos atuais 6,6 bilhões de habitantes (2008) e um passivo ambiental equivalente a um quarto do PIB mundial. Este relatório contábil não convencional é uma prestação de contas global diante dos cenários futuros e sugere ações coordenadas que envolvam aspectos sociais, ambientais, culturais e econômicos.