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1.
Nat Immunol ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918608

RESUMO

Humanized mice are limited in terms of modeling human immunity, particularly with regards to antibody responses. Here we constructed a humanized (THX) mouse by grafting non-γ-irradiated, genetically myeloablated KitW-41J mutant immunodeficient pups with human cord blood CD34+ cells, followed by 17ß-estradiol conditioning to promote immune cell differentiation. THX mice reconstitute a human lymphoid and myeloid immune system, including marginal zone B cells, germinal center B cells, follicular helper T cells and neutrophils, and develop well-formed lymph nodes and intestinal lymphoid tissue, including Peyer's patches, and human thymic epithelial cells. These mice have diverse human B cell and T cell antigen receptor repertoires and can mount mature T cell-dependent and T cell-independent antibody responses, entailing somatic hypermutation, class-switch recombination, and plasma cell and memory B cell differentiation. Upon flagellin or a Pfizer-BioNTech coronavirus disease 2019 (COVID-19) mRNA vaccination, THX mice mount neutralizing antibody responses to Salmonella or severe acute respiratory syndrome coronavirus 2 Spike S1 receptor-binding domain, with blood incretion of human cytokines, including APRIL, BAFF, TGF-ß, IL-4 and IFN-γ, all at physiological levels. These mice can also develop lupus autoimmunity after pristane injection. By leveraging estrogen activity to support human immune cell differentiation and maturation of antibody responses, THX mice provide a platform to study the human immune system and to develop human vaccines and therapeutics.

2.
Proc Natl Acad Sci U S A ; 121(1): e2308502120, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38147647

RESUMO

Rare earth elements (REEs), one of the global key strategic resources, are widely applied in electronic information and national defense, etc. The sharply increasing demand for REEs leads to their overexploitation and environmental pollution. Recycling REEs from their second resources such as waste fluorescent lamps (WFLs) is a win-win strategy for REEs resource utilization and environmental production. Pyrometallurgy pretreatment combined with acid leaching is proven as an efficient approach to recycling REEs from WFLs. Unfortunately, due to the uncontrollable components of wastes, many trials were required to obtain the optimal parameters, leading to a high cost of recovery and new environmental risks. This study applied machine learning (ML) to build models for assisting the leaching of six REEs (Tb, Y, Eu, La, and Gd) from WFLs, only needing the measurement of particle size and composition of the waste feed. The feature importance analysis of 40 input features demonstrated that the particle size, Mg, Al, Fe, Sr, Ca, Ba, and Sb content in the waste feed, the pyrometallurgical and leaching parameters have important effects on REEs leaching. Furthermore, their influence rules on different REEs leaching were revealed. Finally, some verification experiments were also conducted to demonstrate the reliability and practicality of the model. This study can quickly get the optimal parameters and leaching efficiency for REEs without extensive optimization experiments, which significantly reduces the recovery cost and environmental risks. Our work carves a path for the intelligent recycling of strategic REEs from waste.

3.
Proc Natl Acad Sci U S A ; 120(14): e2213130120, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36972452

RESUMO

The value of considerable residual energy in waste Li-ion batteries (WLIBs) is always neglected. At present, "this energy" is always wasted during the discharge process of WLIBs. However, if this energy could be reused, it would not only save a lot of energy but also avoid the discharge step of recycling of WLIBs. Unfortunately, the instability of WLIBs potential is a challenge to efficient utilization of this residual energy. Here, we propose a method that could regulate the cathode potential and current of the battery by simply adjusting the solution pH to utilize 35.08%, 88.4%, and 84.7% of the residual energy for removing heavy metal ions from wastewater, removing Cr (VI) from wastewater, and recovering copper from the solution, respectively. By taking advantage of the high internal resistance R of WLIBs and the sudden change of battery current I caused by iron passivation on the positive electrode of the battery, this method could induce the response of overvoltage η (η = IR) inside the battery at different pH levels to regulate the cathode potential µ of the battery to the three intervals. The potential ranges of the battery cathode corresponding to pH < 3.4, pH ≈ 3.4, and pH > 4 were µ > -0.47V, -0.47V < µ < -0.82V, and µ < -0.82V, respectively. This study provides a promising way and theoretical basis for the development of technologies for reusing residual energy in WLIBs.

4.
Chem Rev ; 123(13): 8718-8735, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37339582

RESUMO

Recycling spent lithium-ion batteries (LIBs) is becoming a hot global issue due to the huge amount of scrap, hazardous, and valuable materials associated with end-of-life LIBs. The electrolyte, accounting for 10-15 wt % of spent LIBs, is the most hazardous substance involved in recycling spent LIBs. Meanwhile, the valuable components, especially Li-based salts, make recycling economically beneficial. However, studies of electrolyte recycling still account for only a small fraction of the number of spent LIB recycling papers. On the other hand, many more studies about electrolyte recycling have been published in Chinese but are not well-known worldwide due to the limitations of language. To build a bridge between Chinese and Western academic achievements on electrolyte treatments, this Review first illustrates the urgency and importance of electrolyte recycling and analyzes the reason for its neglect. Then, we introduce the principles and processes of the electrolyte collection methods including mechanical processing, distillation and freezing, solvent extraction, and supercritical carbon dioxide. We also discuss electrolyte separation and regeneration with an emphasis on methods for recovering lithium salts. We discuss the advantages, disadvantages, and challenges of recycling processes. Moreover, we propose five viable approaches for industrialized applications to efficiently recycle electrolytes that combine different processing steps, ranging from mechanical processing with heat distillation to mechanochemistry and in situ catalysis, and to discharging and supercritical carbon dioxide extraction. We conclude with a discussion of future directions for electrolyte recycling. This Review will contribute to electrolyte recycling more efficiently, environmentally friendly, and economically.

5.
J Environ Manage ; 365: 121533, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38917541

RESUMO

As hazardous waste, the massive generation of spent auto-exhaust catalysts (SACs) puts enormous pressure on environmental management, but provides a rare opportunity for platinum group metals (PGMs) recycling. In this study, machine learning (ML) method was firstly applied to accurately predict regional SACs generation in China for 2025-2050 under five shared socio-economic pathways (SSPs) scenarios, based on which economic and carbon emission reduction potential of PGMs recycling were estimated. Population-GDP-GDPII-GDPIII and Random Forest were determined as key variables and the predictive model. Results indicate that SACs will reach 28.15 million sets (1.7 times that of 2020) and PGMs have economic potential of $890 million by 2050 (SSP1). Furthermore, based on environmental impact assessment, the capture enrichment-electrodeposition purification process is proposed as the best low-carbon recycling solution for SACs. And the integrated recovery process based on copper capture can realize 1.51 million tons of carbon emission reduction in China in 2050 (SSP1). This study can provide decision-making guidance for PGMs recovery and environmental management, as well as technical references for SACs recovery program selection.


Assuntos
Aprendizado de Máquina , Platina , Reciclagem , Platina/química , China , Catálise , Metais/química
6.
Environ Sci Technol ; 57(9): 3496-3504, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36794988

RESUMO

Bromine is an important resource that is widely used in medical, automotive, and electronic industries. Waste electronic products containing brominated flame retardants can cause serious secondary pollution, which is why catalytic cracking, adsorption, fixation, separation, and purification have gained significant attention. However, the bromine resources have not been effectively reutilized. The application of advanced pyrolysis technology could help solve this problem via converting bromine pollution into bromine resources. Coupled debromination and bromide reutilization during pyrolysis is an important field of research in the future. This prospective paper presents new insights in terms of the reorganization of different elements and adjustment of bromine phase transition. Furthermore, we proposed some research directions for efficient and environmentally friendly debromination and reutilization of bromine: 1) precise synergistic pyrolysis should be further explored for efficient debromination, such as using persistent free radicals in biomass, polymer hydrogen supply, and metal catalysis, 2) rematching of Br elements and nonmetal elements (C/H/O) will be a promising direction for synthesizing functionalized adsorption materials, 3) oriented control of the bromide migration path should be further studied to obtain different forms of bromine resources, and 4) advanced pyrolysis equipment should be well developed.


Assuntos
Resíduo Eletrônico , Retardadores de Chama , Bromo , Brometos , Pirólise , Estudos Prospectivos , Resíduo Eletrônico/análise
7.
Environ Sci Technol ; 57(49): 20941-20950, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38032848

RESUMO

Bromine removal is significant in the recycling of waste printed circuit boards (WPCBs). This study found that the critical factors limiting the debromination efficiency of conventional pyrolysis are the formation of coke impeding mass transfer and conversion of bromine into less volatile species, such as coking-Br and copper bromide. According to frontier molecular orbital analysis and thermodynamic equilibrium analysis, C-O bonds of resin are sites prone to electrophilic reactions and copper bromide in residue may undergo hydrolysis; therefore, introducing H2O during pyrolysis was a feasible method for thorough debromination. Through pyrolysis in a water vapor atmosphere, the diffusion limitation of debromination was overcome, and resin was converted into light components; thereby, rapid and deep removal of bromine was achieved. The result indicated that 99.7% of bromine was removed, and the residue could be used as a clean secondary resource. According to life-cycle assessment, pyrolysis of WPCBs in water vapor could be expected to reduce 77 Kt of CO2 emission and increase financial benefits by 60 million dollars, annually.


Assuntos
Resíduo Eletrônico , Vapor , Cobre , Bromo/química , Brometos , Pirólise , Reciclagem/métodos , Resíduo Eletrônico/análise
8.
Environ Sci Technol ; 57(36): 13270-13291, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37610371

RESUMO

With the rise of the new energy vehicle industry represented by Tesla and BYD, the need for lithium-ion batteries (LIBs) grows rapidly. However, owing to the limited service life of LIBs, the large-scale retirement tide of LIBs has come. The recycling of spent LIBs has become an inevitable trend of resource recovery, environmental protection, and social demand. The low added value recovery of previous LIBs mostly used traditional metal extraction, which caused environmental damage and had high cost. Beyond metal extraction, the upcycling of spent LIBs came into being. In this work, we have outlined and particularly focus on sustainable upcycling technologies of toxic electrolyte, cathode, and anode from spent LIBs. For electrolyte, whether electrolyte extraction or decomposition, restoring the original electrolyte components or decomposing them into low-carbon energy conversion is the goal of electrolyte upcycling. Direct regeneration and preparation of advanced materials are the best strategies for cathodic upcycling with the advantages of cost and energy consumption, but challenges remain in industrial practice. The regeneration of advanced graphite-based materials and battery-grade graphite shows us the prospect of regeneration of anode. Furthermore, the challenges and future development of spent LIBs upcycling are summarized and discussed from technological and environmental perspectives.


Assuntos
Grafite , Lítio , Eletrólitos , Íons , Eletrodos
9.
Environ Sci Technol ; 57(22): 8256-8268, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37212265

RESUMO

Due to the dispersed distribution of e-waste and crude disassembly in traditional recycling, valuable metals are not traceable during their life cycle. Meanwhile, incomplete separation between metals and nonmetals reduces the economic value of disassembled parts, which leads to higher environmental costs for metal refining. Therefore, this study proposes a precise disassembly of e-waste to finely classify and recover metals in an environmentally friendly way. First, the macroscopic material flow of e-waste in China (source, flow, scrap, and recycling gap) was measured based on data collected by the government and 109 formal recycling enterprises. The sustainable recycling balance time points for e-waste recycling and scrap volumes were forecast by introducing an additional recycling efficiency. By 2030, the total scrap volume of e-waste is predicted to reach 133.06 million units. For precise disassembly, the main metals and their percentages from these typical e-wastes were measured based on material flow analysis combined with experimental methods. After precise disassembly, the proportion of reusable metals increases significantly. The CO2 emission of precise disassembly with the smelting process was the lowest compared with crude disassembly with smelting and ore metallurgy. The greenhouse gas for secondary metals Fe, Cu, and Al was 830.32, 1151.62, and 716.6 kg CO2/t metal, respectively. The precise disassembly of e-waste is meaningful for building a future resource sustainable society and for carbon emission reduction.


Assuntos
Resíduo Eletrônico , Resíduo Eletrônico/análise , Dióxido de Carbono , Metais , Meio Ambiente , China , Reciclagem/métodos
10.
J Chem Phys ; 158(17)2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37129138

RESUMO

The development of solid-state electrolytes (SSEs) with high lithium ionic conductivities is critical for the realization of all-solid-state Li-ion batteries. Crystal structure distortions, Li polyhedron volumes, and anion charges in SSEs are reported to affect the energy landscapes, and it is paramount to investigate their correlations. Our works uncover the cooperative effect of lithium site distortions, anion charges, and lattice volumes on Li-ion migration energy barrier in superionic conductors of LiMS2 (M = Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) and Li2MO3 (M = Sc, Ti, V, Cr, Mn, Fe, Co, and Ni). Combined with the Least Absolute Shrinkage and Selection Operator analyses, the volume and Continuous symmetrical methods (CSMs) of Li tetrahedral (Tet) sites appear to have a larger effect on the manipulation of Ea for Li migration, compared to that of Li octahedral (Oct) sites, which is further confirmed by the results from the face-centered cubic (fcc) anion lattice model. For the Tet-Oct-Tet Li migration path, the CSM (the volume of Li site) has a negative (positive) correlation with Ea, while for the Oct-Tet-Oct Li migration paths, opposite correlations have been observed. The understanding of the correlation between site preference, anion charge, lattice volume, and structural distortion as well as the prediction model of Ea in terms of these three factors, namely, C-V-D model, could be useful for the design of solid-state electrolytes with lower activation energy.

11.
Angew Chem Int Ed Engl ; 62(5): e202212695, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36375075

RESUMO

Aqueous zinc-ion batteries have drawn increasing attention due to the intrinsic safety, cost-effectiveness and high energy density. However, parasitic reactions and non-uniform dendrite growth on the Zn anode side impede their application. Herein, a multifunctional additive, ammonium dihydrogen phosphate (NHP), is introduced to regulate uniform zinc deposition and to suppress side reactions. The results show that the NH4 + tends to be preferably absorbed on the Zn surface to form a "shielding effect" and blocks the direct contact of water with Zn. Moreover, NH4 + and (H2 PO4 )- jointly maintain pH values of the electrode-electrolyte interface. Consequently, the NHP additive enables highly reversible Zn plating/stripping behaviors in Zn//Zn and Zn//Cu cells. Furthermore, the electrochemical performances of Zn//MnO2 full cells and Zn//active carbon (AC) capacitors are improved. This work provides an efficient and general strategy for modifying Zn plating/stripping behaviors and suppressing side reactions in mild aqueous electrolyte.

12.
Infect Immun ; 90(4): e0065121, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35258318

RESUMO

Intravaginal infection of mice with Chlamydia muridarum has been used for investigating the mechanisms of Chlamydia trachomatis-induced pathogenicity and immune responses. In the current study, the mouse model was used to evaluate the impact of interleukin-27 (IL-27) and its receptor signaling on the susceptibility of the female genital tract to chlamydial infection. Mice deficient in IL-27 developed significantly shortened courses of chlamydial infection in the female genital tract. The titers of live Chlamydia recovered from the genital tract of IL-27-deficient mice declined significantly by day 7 following intravaginal inoculation. These observations suggest that IL-27 may promote chlamydial infection in the female mouse genital tract. This conclusion was validated using IL-27 receptor (R)-deficient mice. Further, the reduction in chlamydial burden corelated with the increase in gamma interferon (IFN-γ) and IL-17 in the genital tract tissues of the IL-27R-deificent mice. However, depletion of IFN-γ but not IL-17 from the IL-27R-deificent mice significantly increased the chlamydial burden, indicating that IL-27 may mainly suppress IFN-γ-mediated immunity for promoting chlamydial infection. Finally, knockout of IL-27R from T cells alone was sufficient for significantly shortening the infectious shedding courses of Chlamydia in the mouse genital tract. The above-described results have demonstrated that Chlamydia can activate IL-27R signaling in Th1-like cells for promoting its infection in the female genital tract, suggesting that attenuating IL-27 signaling in T cells may be used for enhancing genital tract immunity against chlamydial infection.


Assuntos
Infecções por Chlamydia , Chlamydia muridarum , Interleucina-27 , Interleucinas/metabolismo , Infecções do Sistema Genital , Animais , Chlamydia trachomatis , Feminino , Genitália Feminina , Humanos , Interferon gama , Masculino , Camundongos , Camundongos Endogâmicos C57BL
13.
Environ Sci Technol ; 56(23): 17396-17409, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36354075

RESUMO

With the widespread photovoltaic deployment to achieve the net-zero energy goal, the resulting photovoltaic waste draws attention. In China, considerable steps have not been taken for photovoltaic waste management. The lack of relevant scientific information on photovoltaic waste brings difficulties to the establishment of photovoltaic waste regulatory systems. In this study, the necessity and feasibility of photovoltaic waste recovery were investigated. In China, the photovoltaic waste stream was quantified as 48.67-60.78 million t in 2050. In photovoltaic waste, indium, selenium, cadmium, and gallium were in high risk, judging by the metal criticality analysis, which meant that their recovery was significant to alleviate the resource shortage. The full recovery method was proved to reduce the environmental burdens most. For cost and benefit analysis, the net present value/size was -1.02 $/kg according to the current industrial status. However, it can be profitable with the recovery of silver. This study provides scientific and comprehensive information for photovoltaic waste management in China and is expected to promote the sustainable development of photovoltaic industry.


Assuntos
Reciclagem , Gerenciamento de Resíduos , Estudos de Viabilidade , Gerenciamento de Resíduos/métodos , China
14.
J Immunol ; 204(5): 1146-1157, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31932498

RESUMO

Upon activation by CD40 or TLR signaling, B lymphocytes activate NF-κB to induce activation-induced cytidine deaminase and, therefore, Ig class switch DNA recombination, as central to the maturation of the Ab and autoantibody responses. In this study, we show that NF-κB activation is boosted by colocalization of engaged immune receptors, such as CD40, with RAB7 small GTPase on mature endosomes, in addition to signals emanating from the receptors localized on the plasma membrane, in mouse B cells. In mature endosomes, RAB7 directly interacts with TRAF6 E3 ubiquitin ligase, which catalyzes K63 polyubiquitination for NF-κB activation. RAB7 overexpression in Cd19+/creRosa26fl-STOP-fl-Rab7 mouse B cells upregulates K63 polyubiquitination activity of TRAF6, enhances NF-κB activation and activation-induced cytidine deaminase induction, and boosts IgG Ab and autoantibody levels. This, together with the extensive intracellular localization of CD40 and the strong correlation of RAB7 expression with NF-κB activation in mouse lupus B cells, shows that RAB7 is an integral component of the B cell NF-κB activation machinery, likely through interaction with TRAF6 for the assembly of "intracellular membrane signalosomes."


Assuntos
Linfócitos B/imunologia , Endossomos/imunologia , Switching de Imunoglobulina , NF-kappa B/imunologia , Fator 6 Associado a Receptor de TNF/imunologia , Ubiquitinação/imunologia , Proteínas rab de Ligação ao GTP/imunologia , Animais , Antígenos CD19/genética , Antígenos CD19/imunologia , Linfócitos B/citologia , Endossomos/genética , Camundongos , Camundongos Transgênicos , NF-kappa B/genética , Fator 6 Associado a Receptor de TNF/genética , Ubiquitinação/genética , Proteínas rab de Ligação ao GTP/genética , proteínas de unión al GTP Rab7
15.
Phys Chem Chem Phys ; 24(48): 29512-29519, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36448472

RESUMO

The solvation of cations is one of the important factors that determine the properties of electrolytes. Rational solvation structures can effectively improve the performance of various electrochemical energy storage devices. Water-in-Salt (WIS) electrolytes with a wide electrochemically stable potential window (ESW) have been proposed to realize high cell potential aqueous electrochemical energy storage devices relying on the special solvation structures of cations. The ratio of H2O molecules participating in the primary solvation structure of a cation (a cation hydration ratio) is the key factor for the kinetics and thermodynamics of the WIS electrolytes under an electric field. Here, acetates with different cations were used to prepare WIS electrolytes. And, the effect of different cation hydration ratios on the properties of WIS electrolytes was investigated. Various WIS electrolytes exhibited different physicochemical properties, including the saturated concentration, conductivity, viscosity, pH values and ESW. The WIS electrolytes with a low cation hydration ratio (<100%, an NH4-based WIS electrolyte) or a high cation hydration ratio (>100%, a K-based WIS electrolyte and a Cs-based WIS electrolyte) exhibit more outstanding conductivity or a wide ESW, respectively. SCs constructed from active carbon (AC) and these WIS electrolytes exhibited distinctive electrochemical properties. A SC with an NH4-based WIS electrolyte was characterized by higher capacity and better rate capability. SCs with a K-based WIS electrolyte and a Cs-based WIS electrolyte were characterized by a wider operating cell potential, higher energy density and better ability to suppress self-discharge and gas production. These results show that a WIS electrolyte with a low cation hydration ratio or a high cation hydration ratio is suitable for the construction of power-type or energy-type aqueous SCs, respectively. This understanding provides the foundation for the development of novel WIS electrolytes for the application of SCs.

16.
Environ Res ; 211: 113101, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35292242

RESUMO

As a kind of typical veterinary drug, fluoroquinolone antibiotics (FQs) are widely used in the field of livestock and poultry breeding, but these FQs escape to surrounding soil through various pathways, polluting soil through long-term accumulation. Current study proposed a clean technology named thermal desorption to deal with FQs contaminated soils. It was observed that time, temperature and soil particle size were the critical factors in FQs thermal desorption. Results of the study showed that higher temperature was more effective in the removal of FQs, while removal of FQs attached with finer particles was more difficult compared to coarse particles. Fine soil particles (0.6-0.85 mm) were decontaminated up 99.4% when treated with 400 °C for 60min. Thermal desorption of FQs from contaminated soil was governed by first-order kinetics. Based on the detection of exhaust gas components, a possible thermal desorption mechanism was proposed. Study suggested that thermal desorption was a clean and effective remediation method to treat FQs-contaminated soils without generating any further waste.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Animais , Fluoroquinolonas/análise , Gado , Aves Domésticas , Solo , Poluentes do Solo/análise
17.
Angew Chem Int Ed Engl ; 61(50): e202213640, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36282184

RESUMO

Exploring the pathways for photocatalytic dissolution of precious metals (PMs) is crucial for optimizing recovery. In this work, we systematically investigated the selectivity and solvation effects observed for dissolution by focusing on photocatalysis, precious metals and solvents. By combining transient characterization, reaction kinetics, and density functional theory, we determined that the radicals generated in photocatalysis were the key active species in the entire reaction. The cyano functional group in the solvent was the driving factor for dissolution of gold, and the importance of chlorine radicals for dissolution of platinum group precious metals was further confirmed. In addition, the catalytic properties of different precious metals can promote different transformations of functional groups, leading to selective dissolution. The structures of photocatalytic precious metal leaches also precisely explains the special coordination forms of precious metals and functional group ligands.

18.
Nat Immunol ; 10(5): 540-50, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19363484

RESUMO

The cytidine deaminase AID (encoded by Aicda in mice and AICDA in humans) is critical for immunoglobulin class-switch recombination (CSR) and somatic hypermutation (SHM). Here we show that AID expression was induced by the HoxC4 homeodomain transcription factor, which bound to a highly conserved HoxC4-Oct site in the Aicda or AICDA promoter. This site functioned in synergy with a conserved binding site for the transcription factors Sp1, Sp3 and NF-kappaB. HoxC4 was 'preferentially' expressed in germinal center B cells and was upregulated by engagement of CD40 by CD154, as well as by lipopolysaccharide and interleukin 4. HoxC4 deficiency resulted in impaired CSR and SHM because of lower AID expression and not some other putative HoxC4-dependent activity. Enforced expression of AID in Hoxc4(-/-) B cells fully restored CSR. Thus, HoxC4 directly activates the Aicda promoter, thereby inducing AID expression, CSR and SHM.


Assuntos
Linfócitos B/imunologia , Citidina Desaminase/genética , Regulação da Expressão Gênica/imunologia , Proteínas de Homeodomínio/imunologia , Switching de Imunoglobulina/imunologia , Hipermutação Somática de Imunoglobulina/imunologia , Animais , Sequência de Bases , Sequência Conservada , Citidina Desaminase/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Citometria de Fluxo , Centro Germinativo/citologia , Centro Germinativo/imunologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nódulos Linfáticos Agregados/citologia , Nódulos Linfáticos Agregados/imunologia , Regiões Promotoras Genéticas/genética , Recombinação Genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/citologia , Baço/imunologia , Linfócitos T
19.
Environ Sci Technol ; 55(15): 10724-10733, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34269567

RESUMO

While CIGS solar cell has been experiencing an expanded photovoltaic market and increasing research interest in cell design, its treatment after obsoletion remains an upcoming issue. The heavy metals involved, such as Cd, can threat the environment, while strategic resources, such as rare metals In and Ga, offer a great recycling oppotunity. However, due to its multimetal feature, traditional recycling methodology shows poor separation-extraction efficiency and additional environmental burdens with intense reagent consumption and waste generation. Here, we report a sequential electrodeposition method for pure metal recycling from this Cu-In-Cd-Ga quaternary system in a more environmentally friendly and efficient manner. Stability constant-corrected redox potential supplemented with metal electroreduction tests predicts well the potential window for sequential electrodeposition. Cu and In electrodeposition shows 100% separation with high Coulombic efficiency (>80%), whereas Ga electrodeposition presents slower kinetics and performs better at a pH of 2.5. Environmental impact assessment indicates that the proposed recycling route allows remarkable reduction of global warming and toxicity impacts compared with metal production from virgin mining and reference processes. We further unveiled the applicability of the electrodeposition technique in the context of anthropogenic mineral recycling, emphasizing resource sustainability and cleaner production.


Assuntos
Resíduo Eletrônico , Metais Pesados , Cádmio , Resíduo Eletrônico/análise , Galvanoplastia , Meio Ambiente , Metais Pesados/análise , Reciclagem
20.
Environ Sci Technol ; 55(6): 4027-4036, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33663209

RESUMO

Every year, billions of tons of lignite are burnt to generate electricity, meanwhile generating large amounts of coal fly ash (CFA) that is regarded as an industrial waste. During lignite combustion, arsenic and scarce metals are simultaneously volatilized in the form of oxide into CFA. This study proposed an effective vacuum distillation method to remove As and recover Ge and W from CFA. The feasibility of separating As and recycling Ge and W from CFA was verified by the theoretical analysis. The experimental result indicated that the removal ratio of As was 96 ± 1% and the contents of Ge and W reached 0.75 ± 0.023 and 0.24 ± 0.016 wt % in the residue, which were enriched 17.2 and 1.2 times, respectively, at a temperature of 550 °C, with 50 wt % sulfurizing agent added under pressure of 1 Pa and 240 min of heating. For the condensed product, chemical species As2S3 and As4S4 were detected by X-ray photoelectron spectroscopy analysis. For Ge and W in the residue, GeOx (x < 2), GeS, WOx (x < 3), and WS2 were the main chemical species. The potential mechanism involved in the release of arsenic from CFA, vacuum sulfurization, evaporation, and condensation was proposed. The kinetic analysis indicated that the apparent activation energy (Eα) was 31.24 kJ mol-1. Those results encourage further exploration of vacuum separation technology to environmentally friendly recycle CFA.


Assuntos
Arsênio , Germânio , Carvão Mineral/análise , Cinza de Carvão/análise , Destilação , Indicadores e Reagentes , Cinética , Tungstênio , Vácuo
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