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1.
Adv Sci (Weinh) ; : e2400687, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647425

RESUMO

The development of functional textiles combining conventional apparel with advanced technologies for personal health management (PHM) has garnered widespread attention. However, the current PHM textiles often achieve multifunctionality by stacking functional modules, leading to poor durability and scalability. Herein, a scalable and robust PHM textile is designed by integrating electrical, radiative, and solar heating, electromagnetic interference (EMI) shielding, and piezoresistive sensing performance onto cotton fabric. This is achieved through an uncomplicated screen-printing process using silver paste. The conductivity of the PHM textile is ≈1.6  ×  104 S m-1, ensuring an electric heating temperature of ≈134 °C with a low voltage of 1.7 V, as well as an EMI shielding effectiveness of ≈56 dB, and human motion monitoring performance. Surprisingly, the radiative/solar heating capability of the PHM textile surpasses that of traditional warm leather. Even after undergoing rigorous physical and chemical treatments, the PHM textile maintains terrific durability. Additionally, the PHM textile possesses maneuverable scalability and comfortable wearability. This innovative work opens up new avenues for the strategic design of PHM textiles and provides an advantageous guarantee of mass production.

2.
Langmuir ; 40(17): 9215-9223, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38635343

RESUMO

Designing and developing high-performance shielding materials against electromagnetic interference is of utmost importance due to the rapid advancement of wireless telecommunication technologies. Such materials hold both fundamental and technological significance. A three-stage process is presented for creating ultralight, flexible aerogels from biomass to shield against electromagnetic interference. Collagen fibers sourced from leather solid waste are used for: (i) freeze-drying preparation of collagen fibers/poly(vinyl alcohol) (PVA) aerogels, (ii) adsorption of silver nanowires (AgNWs) onto collagen fiber/PVA aerogels, and (iii) Hydrophobic modification of collagen fiber/PVA/AgNWs aerogels with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (POTS). Scanning electron microscopy studies reveal that an interweaving of AgNWs and collagen fiber/PVA porous network has formed a conductive network, exhibiting an electrical conductivity of 103 S·m-1. The electromagnetic interference shielding effectiveness reached more than 62 dB, while the density was merely 5.8 mg/cm3. The collagen fiber/PVA/AgNWs/POTS aerogel displayed an even better electromagnetic shielding efficiency of 73 dB and water contact angle of 147°. The study results emphasize the distinctive capacity of leather solid waste to generate cost-effective, ecofriendly, and highly efficient electromagnetic interference shielding materials.

3.
Mikrochim Acta ; 191(4): 219, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530477

RESUMO

Hydroxypropyl chitosan-Cs3Bi2Cl9 perovskite quantum dots (HPCS-PQDs) were synthesized by a simple ligand-assisted reprecipitation method via green hydroxypropyl chitosan as the ligand and used as the specific signal of a fluorescence probe to achieve the highly sensitive detection of hexavalent chromium (Cr(VI)) and compared with chitosan-Cs3Bi2Cl9 QDs (CS-PQDs). HPCS-PQDs with multiple active hydroxyl passivations were found to enhance the photoluminescence quantum yield (PLQY) by 90%. After being placed in aqueous solution and irradiated with ultraviolet light for 96 h the fluorescence intensity of HPCS-PQDs remained above 60%. The blue emission of HPCS-PQDs has a good selectivity and short response time (30 s) for Cr(VI). A good linear relationship is established between the fluorescence quenching rate of the HPCS-PQDs and concentration of Cr(VI) from 0.8 to 400 µM, with a limit of detection (LOD) of 0.27 µM. The fluorescence quenching mechanism is the static quenching and internal filtration effect caused by HPCS-PQDs forming a non-fluorescent ground-state complex with Cr(VI). The sensor can not only be used to detect Cr(VI) in water samples with high accuracy but can also be prepared as a test paper for the detection for Cr(VI).

4.
Small ; 20(15): e2308194, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009488

RESUMO

Passive heating textiles (PHTs) have drawn increasing attention due to the advantages of energy-conservation heating. However, the heating capabilities of current PHTs are typically static and non-tunable, presenting poor adaptation to dynamic winter. Herein, a novel Janus textile with tunable heating modes is developed by constructing a customized structure with asymmetric optical properties. This Janus textile is created by coating one side of a cotton fabric with silver nanowires (AgNWs) and then applying transition metal carbides/nitrides (MXene) to the other side. The MXene side exhibits high solar absorptivity and low mid-infrared emissivity, while the AgNWs side has moderate solar absorptivity and mid-infrared emissivity. This structure ensures that the solar and radiative heating temperatures of the MXene side are 16 °C and 1.7 °C higher than those of the AgNWs side. This distinction allows for on-demand, accurate adjustments in solar and radiative heating capabilities by flipping the textile according to ambient temperature. Furthermore, this innovative design also features desired electric heating, thermal camouflage, self-cleaning and antibacterial properties, electromagnetic interference shielding, durability, and wearability. The Janus textile enables precise thermoregulation of the human body to adapt to variable cold weather, making it essential for optimal personal thermal management and climate change mitigation.

5.
Langmuir ; 39(49): 18011-18021, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38016011

RESUMO

Porous structure design and reversible regulation of pore size during adsorption-desorption are crucial to the removal of pollutants in water such as Cr(VI). In this paper, micropores and switchable mesopores were constructed on MCM-41 to further improve adsorption-desorption performance of Cr(VI) via the confinement effect of micropores and opening and closing of mesopores. 2-Vinylpyridine was introduced and polymerized into the pores and on the pore mouth of MCM41 modified by C═C group (AM41) under the irradiation of ultraviolet light. The obtained samples (PM41) possessed mesopores (2.73 nm) and micropores (1.36 nm), where mesopores could open or close under different pH and micropores showed the confinement effect because their pore size is close to Cr(VI) diameter (0.87 nm). Compared with MCM-41, the introduction of poly(2-vinylpyridine) enhanced obviously its adsorptive ability and it trapped most of the Cr(VI) (99%) in solution, 12 times higher than that of the parent sample. The change of pore size is favorable to the cycle performance, and after 3 times recycling, the removal rate of Cr(VI) by PM41-20 remained above 88%. Langmuir isotherm showed a better data correlation than the Freundlich model. Cr(VI) in solution was removed by electrostatic interaction between the pyridine group and Cr(VI) and the confinement effect from micropores.

6.
ACS Appl Mater Interfaces ; 15(36): 43205-43215, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37638771

RESUMO

Self-propelled separation materials, that is, motor, are one of the keys to realizing smart oil-water separation. Although three-dimensional sponges such as commercial melamine sponge (MS) exhibit excellent oil-water separation ability, they cannot move by themselves on water. Aiming at solving this problem, a polydimethylsiloxane (PDMS) and molybdenum disulfide (MoS2) modified MS motor (PDMS@MS/MoS2) with an asymmetric multilayer structure was prepared, in which the photothermal layer MoS2 provided the propelling force for the motor under infrared light irradiation, and the middle layer PDMS was used as the superhydrophobic modified agent and adhesive agent between commercial MS and MoS2 powder. PDMS coated MS (PDMS@MS) as the superhydrophobic layer showed good superhydrophobic ability (153.1°) and oil-water separation capacity (52.33 g/g to liquid paraffin). Furthermore, the introduction of MoS2 made the speed of the sponge motor reach 8.27 mm s-1 with a removal quantity of 12.20 g/g for cyclohexane. After recycling 8 times, the contact angle, cyclohexane capturing amount, and average velocity of the motor were 150.3°, 11.40 g/g, and 8.41 mm/s, respectively. Meanwhile, PDMS@MS/MoS2 kept a similar light-propelling velocity (∼8 mm) at different pH values and in simulated seawater, demonstrating that the light-propelling motor possessed a good cycle and practical performance, which provides a possibility for the directional light propulsion of a sponge motor in oil-water separation.

7.
Int J Biol Macromol ; 247: 125829, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37453634

RESUMO

The non-degradable traditional polyethylene (PE) mulch film has caused great harm to both the ecological environment as well as human health. Therefore, the biodegradable bone gelatin (B-Gel) was innovatively selected to build the mulch film. To further enhance the toughness of the B-Gel mulch films, a POSS star-shaped polymer/bone gelatin (P(POSS-AGE-HEA)/B-Gel) composite was prepared by introducing POSS star-shaped polymer into B-Gel via in situ polymerization using polyhedral oligomeric silsesquioxane (POSS), allyl glycidyl ether (AGE) and hydroxyethyl acrylate (HEA) as raw material, and then was cast to obtain the P(POSS-AGE-HEA)/B-Gel mulch film. The epoxy group of POSS star-shaped polymer with the -COOH and -NH2 of B-Gel forms a covalent bond, and the hydroxyl group with the active groups of B-Gel forms hydrogen bonds. Meanwhile, the multiple side chains of POSS star-shaped polymer are intertwined with B-Gel. These covalent and hydrogen bonds as sacrificial bonds for effective energy dissipation giving the bone gelatin-based film excellent mechanical properties with a tensile strength of 7.56 ± 0.64 MPa and elongation at break of 197.49 ± 17.63 %. Additionally, it also demonstrated sound water vapor barrier, surface hydrophobicity, light transmittance and the effect of facilitating the growth and germination ratio (93.75 %) of wheat.


Assuntos
Gelatina , Polímeros , Humanos , Polímeros/química , Resistência à Tração
8.
Int J Biol Macromol ; 241: 124493, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37086771

RESUMO

The abuse of chrome tanning agent in leather processing has caused great harm to human health and the natural environment. We use tremella polysaccharides (TP), lentinan (LNT) and konjac gum (KG) as raw materials, and sodium periodate as oxidant to prepare the corresponding polysaccharide tanning agent. Tremella polysaccharide was selected as the best tanning agent according to the shrinkage temperature, and the subsequent experiments were carried out. Tremella polysaccharide (TP) as raw material and sodium periodate as an oxidant, dialdehyde tremella polysaccharide (DTP) was prepared and applied in leather tanning. The effects of different oxidation conditions (sodium periodate dosage, temperature, pH, and reaction time) on the shrinkage temperature of DTP tanned leather were studied. The change of shrinkage temperature showed that the dosage of sodium periodate had the greatest influence on the shrinkage temperature. Therefore, the effects of different dosage of sodium periodate on the aldehyde content and molecular weight of DTP were investigated, including the analysis of physical properties and microstructure of tanned leather. In general, the increase of sodium periodate dosage was found to increase the aldehyde content and reduce the molecular weight, which was more conducive to leather tanning.


Assuntos
Polissacarídeos , Curtume , Humanos , Aldeídos , Oxidantes , Cromo/análise
9.
Carbohydr Polym ; 304: 120511, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36641159

RESUMO

The development of sustainable and eco-friendly leather industry requires green tanning agents because of unbounded chromium (easily converted into hazardous Cr-VI) in chrome tanned leather. In this study, a chrome-free tanning agent (OS-LDHs) was established by integrating layered double hydroxide (magnesium aluminum zirconium hydrotalcite, LDHs) with starch derivatives. A series of oxidized starch (OS) were prepared as masking agents for LDHs tanning process. Among them, the weight-average molecular weight (Mw) of 1685 g/mol could be reached, which will promise the well-distribution of OS. The SEM and EDS analysis confirmed the uniform penetration of OS-LDHs, avoiding accumulation on the surface of crust leather. Notably, leather tanned by OS-LDHs achieved shrinkage temperature of 66.7 °C, porosity of 75.51 % and tear strength of 66.7 N/mm. Not only the hydrogen bond but also the coordination between NH2, COOH in collagen and OS-2-LDHs improved the thermal stability of leather without destroying the collagen triple helix.


Assuntos
Amido , Curtume , Indústrias , Cromo/química , Colágeno/química
10.
ACS Appl Mater Interfaces ; 14(33): 38077-38089, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35971686

RESUMO

High-performance flexible conductive films are highly promising for the development of wearable devices, artificial intelligence, medical care, etc. Herein, a three-step procedure was developed to produce electromagnetic interference (EMI) shielding, Joule heating, and a hydrophobic nanofiber film based on hydrolysate of waste leather scraps (HWLS): (i) electrospinning preparation of the HWLS/polyacrylonitrile (PAN)/zeolitic imidazolate framework-67 (ZIF-67) nanofiber film, (ii) carbonization of the HWLS/PAN/ZIF-67 nanofiber film, and (iii) coating of the carbon nanofiber@cobalt (Co@CNF) nanofiber film with perfluorooctyltriethoxysilane (POTS). The X-ray diffraction results showed that metal nanoparticles and amorphous carbon had obvious peaks. The micromorphology results showed that metal nanoparticles were coated with carbon nanofibers. The conductivity and shielding efficiency of the carbon nanofiber film with 250 µm thickness could reach 45 S/m and 49 dB, respectively, and absorption values (A > 0.5) were higher than reflection (R) values for the Co@CNF nanofiber film, which indicated that the contribution of absorption loss was more significant than that of reflection loss. Ultrafast electrothermal response performances were also achieved, which could guarantee the normal functioning of films in cold conditions. The water contact angle of the Co@CNF@POTS nanofiber film was ∼151.3°, which displayed a self-cleaning property with water-proofing and antifouling. Absorption-dominant and low-reflection EMI shielding and electrothermal films not only showed broad application potential in flexible wearable electronic devices but also provided new avenues for the utilization of leather solid waste.

11.
Inorg Chem ; 61(17): 6547-6554, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35447028

RESUMO

The toxicity of the Pb element limits the large-scale application of inorganic cesium-lead halide (CsPbX3, with X = Cl, Br, and I) perovskite nanocrystals (NCs). Pb-free cesium-tin halide (CsSnX3) NCs have emerged as a viable alternative because of its excellent photoelectric conversion efficiency. However, the applications are hampered by its poor stability and low photoluminescence quantum yield (PLQY). In this study, extraordinarily stable CsSnCl3 NCs were prepared by exploiting bone gelatin as surface capping agents, which retain 95% of the photoluminescence intensity in water for 55 h. Additionally, after bone gelatin encapsulation, the PLQY of CsSnCl3 NCs was found to increase from 2.17% to 3.13% for the uncapped counterparts because of an improved radiative recombination rate. With such remarkable optical properties of the bone gelatin-CsSnCl3 NCs, metal ions like Fe3+ in aqueous solutions can be readily detected and monitored, signifying the potential application of such stable bone gelatin-CsSnCl3 NCs in the development of fluorescence sensors and detectors.


Assuntos
Gelatina , Nanopartículas , Compostos de Cálcio , Césio , Óxidos , Titânio , Água
12.
Inorg Chem ; 61(14): 5672-5682, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35333522

RESUMO

Lead halide perovskite quantum dots (QDs) are controversial due to their high lead content. Tin, a low-toxic element with an outer electronic structure similar to that of Pb, becomes a strong candidate for preparing lead-free perovskite QDs. However, tin-based perovskite QDs, especially CsSnCl3 QDs, exhibit poor environmental stability. Herein, we proposed an strategy for highly stable CsSnCl3 QDs using an ionic liquid as a solvent and antioxidant and gelatin as a multidentate ligand and coating material through an in situ method ([AMIM]Cl/gelatin-QDs). The results showed that the abundant active groups of gelatin served as the nucleation growth center for QDs and further passivated QDs. At the same time, the long molecular chain of gelatin can coat the QDs to isolate the environment and fully protect QDs, and the size of QDs grown in gelatin was 5-10 nm. In addition, the oxidation resistance of ionic liquids and the halogen-rich environment formed also played an important role. Even if [AMIM]Cl/gelatin-QDs were treated with water and ultraviolet light simultaneously, its remaining fluorescence intensity was still above 60% within 72 h. Meaningfully, QDs endowed the composite system mildew resistance, which can resist the erosion of gelatin by molds, thereby realizing the system's long-term protection toward CsSnCl3 QDs.

13.
Polymers (Basel) ; 14(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35267788

RESUMO

In this work, p-double network (p-DN) hydrogels were formed by the interpenetration of poly(2-acrylamide-2-methylpropanesulfonic acid-copolymer- acrylamide) microgel and polyacrylamide. The initial viscosity of prepolymer solution before hydrogel polymerization, mechanical properties, temperature and salt resistance of the hydrogels were studied. The results showed that the initial viscosity of the prepolymer was less than 30 mP·s, and the p-DN hydrogel not only exhibited high compressive stress (37.80 MPa), but the compressive strength of p-DN hydrogel could also reach 23.45 MPa after heating at 90 °C, and the compressive strength of p-DN hydrogel could reach 13.32 MPa after soaking for 24 h in the solution of 5W mineralization. In addition, the cyclic loading behavior of hydrogel was studied. The dissipation energy of p-DN hydrogel under 80% strain was 7.89 MJ/m3, which effectively dissipated energy. Meanwhile, p-DN hydrogel maintained its original form while breaking the pressure greater than 30 MPa, indicating excellent plugging performance.

14.
J Colloid Interface Sci ; 613: 396-405, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35042037

RESUMO

With the rapid development of wireless telecommunication technologies, it is of fundamental and technological significance to design and engineer high-performance shielding materials against electromagnetic interference (EMI). Herein, a three-step procedure is developed to produce hydrophobic, flexible nanofiber films for EMI shielding and pressure sensing based on hydrolysate of waste leather scraps (HWLS): (i) electrospinning preparation of HWLS/polyacrylonitrile (PAN) nanofiber films, (ii) adsorption of silver nanowires (AgNWs) onto HWLS/PAN nanofiber films, and (iii) coating of HWLS/PAN/AgNWs nanofiber films with polydimethylsiloxane (PDMS). Scanning electron microscopy studies show that AgNWs are interweaved with HWLS/PAN nanofibers to form a conductive network, exhibiting an electrical conductivity of 105 S m-1 and shielding efficiency of 65 dB for a 150 µm-thick HWLS/PAN/AgNWs film. The HWLS/PAN/AgNWs/PDMS film displays an even better electromagnetic shielding efficiency of 80 dB and a water contact angle of 132.5°. Results from this study highlight the unique potential of leather solid wastes for the production of high-performance, environmentally friendly, and low-cost EMI shielding materials.

15.
Int J Biol Macromol ; 200: 557-565, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35066021

RESUMO

As a kind of renewable biological resource, leather collagen is the raw material of leather industry. The chrome tanning modified collagen has high humidity and heat resistance, but there are some defects such as environmental pollution, harm to human health and shortage of chromium resources, so it is urgent to research chromium-free tanning to achieve clean modified colloidal. In the chromium-free tanning system, the modification of skin fibrin by bio-based material has the significance of environmental protection. Sodium alginate can be used as crosslinking agent to stabilize collagen. In this study, the polyhedral oligomeric silsesquioxane (POSS) grafted oxidized sodium alginate polymer composite (POSS-OSA-MAA) containing aldehyde group was prepared by two steps. Firstly, POSS grafted sodium alginate polymer composite (POSS-SAG-MAA) was prepared by graft polymerization with POSS, sodium alginate (SAG) and methacrylic acid (MAA) as raw materials. Then POSS-OSA-MAA was obtained by oxidation of POSS-SAG-MAA with sodium periodate. The aldehyde group highest concentration in POSS-OSA-MAA was 3.26 mmol•g-1, and the tanned leather shrinkage temperature was 73.1 °C. The X-ray photoelectron spectroscopy showed that POSS-OSA-MAA could form Schiff base structure with amino-containing substances and form multiple points crosslinking, and POSS-OSA-MAA could improve the shrinkage temperature and thermal stability of skin collagen.


Assuntos
Curtume
16.
J Environ Manage ; 302(Pt A): 114013, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34735834

RESUMO

In the present study, an investigation was conducted on the removal of polydiallyldimethylammonium chloride-acrylic-acrylamide-hydroxyethyl acrylate/ZnO nanocomposites (PDM/ZnO) through biodegradation and Fenton process coupled treatments. As revealed from the results of the chemical oxygen demand, the total organic carbon, the biochemical oxygen demand and the CO2 production analysis, PDM/ZnO could be partially biodegraded. The optimal initial pH, the mixed liquid suspended solids concentration and additional carbon source (glucose) dosage in the biodegradation were 7.0, 4.0 g/L and 1.0 g/L, respectively. On the whole, NaCl, the coexisted metal cations (Cu2+, Zn2+ and Cr3+) and additional NH4Cl inhibited the biodegradation of PDM/ZnO. PDM/ZnO was suggested to adversely affect on microbial community structure and activity. Optimum conditions for Fenton treatment were 50 mg/L Fe2+, 20 mL/L H2O2 and pH 2.0. Biodegradation showed that 64% of PDM/ZnO was removed. Besides, the combination of Fenton post-treatment could achieve an over 97% removal of PDM/ZnO. Thus, Fenton process combined biodegradation pre-treatment can act as an effective method to remove PDM/ZnO.


Assuntos
Poluentes Químicos da Água , Óxido de Zinco , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Peróxido de Hidrogênio , Oxirredução , Poluentes Químicos da Água/análise
17.
J Colloid Interface Sci ; 599: 88-99, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33933800

RESUMO

Amphiphilic Janus particles are characterized by their anisotropic morphology and unique physical and chemical properties. In the present research, amphiphilic Janus particles were used as stabilizing agents to prepare a fluorine-containing polyacrylate composite emulsion. The influences of the structure and dosage of amphiphilic Janus SiO2 particles and the amount of fluorine-containing monomer hexafluorobutyl methacrylate on the stability of the composite emulsion were investigated. It was noticed that when the hydrophilic and hydrophobic groups of Janus SiO2 particles were polyacrylamide and polymethyl methacrylate, respectively, the stabilization of the polyacrylate emulsion with Janus SiO2 particles was achieved. When 0.3 wt% of polyacrylamide/polymethyl methacrylate amphiphilic Janus SiO2 particles and 8 wt% of hexafluorobutyl methacrylate were used, a stable composite emulsion was obtained. The conversion rate reached 98.7% with an average particle size of 500 nm. The composite emulsion was applied for fabric finishing. The water contact angle of the fabric increased from 21.4° to 140.2°, demonstrating its greatly improved hydrophobicity. Therefore, it could be inferred that the synergistic effect of amphiphilic Janus SiO2 nanoparticles and hexafluorobutyl methacrylate improved the water resistance of the latex film.

18.
Environ Sci Pollut Res Int ; 28(29): 39014-39025, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33743156

RESUMO

In this study, a cleaner approach to a 'sandwich' chrome-less tanning for cattle hide upper suede leather based on polycarboxylate/montmorillonite nanocomposite (PCM) has been developed. The chromium was reduced both in tanning process and retanning process. Hydrothermal stability, mechanical strength, and organoleptic properties of the leather were closed to traditional chrome tanning. The important advantage of the cleaner tanning approach is that the chromium load in wastewater decreased from 2302 mg/L in tanning process and 2919 mg/L in retanning process to 131 and 257 mg/L, respectively. Moreover, SEM analyses demonstrated that the leather tanned by PCM achieved loose fiber structure and flaky montmorillonite deposition both in intra-triple and inter-triple helix. XRD results suggested that basic chromium sulfate and PCM may form more complexation with the helix chain of collagen fiber, resulting in structural distortion of collagen molecules without destroying the triple helical structure. EDS liner scanning indicated the distribution of chromium on the cross section of the leather. Trypsin degradation curves revealed the cleaner approach might increase the degradation of leather, and the economic analysis results showed that the tanning costs could be reduced and increased the economic benefits.


Assuntos
Nanocompostos , Curtume , Animais , Bentonita , Bovinos , Cromo/análise , Colágeno , Resíduos Industriais/análise
19.
J Hazard Mater ; 403: 123967, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33265008

RESUMO

Lead-halide perovskite nanocrystals (NCs) are limited in commercial applications due to their high lead content. Developing lead-free perovskite NCs becomes a new choice. Among them, the tin-halide perovskite NCs exhibit the excellent photoelectric conversion efficiency, but has worse stability. Herein we describe an effective approach to the preparation of highly-stable all-inorganic tin-based perovskite NCs by using gelatin via interfacial passivation and coating, which leads to the retention of 77.46% of photoluminescence intensity even after the dispersion of the NCs in water for 3 d. The results show that gelatin form a "rich ligand" state on NC surface, such as amino-Sn, carboxylate-Sn and halogen-ammonium hydrogen-bonding interactions. The amino-Sn coordination would be replaced by carboxylate-Sn coordination when NCs are dispersed in polar-media. Meanwhile, gelatin is imparted excellent anti-mildew properties by NCs, which ensures long-lasting effect to NCs. This will promote the stability and sustainable development of the perovskite device.

20.
Ecotoxicol Environ Saf ; 188: 109919, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31733935

RESUMO

In this paper, a process combining biodegradation and Fenton oxidation was proposed for the removal of polydiallyldimethylammonium chloride-acrylic-acrylamide-hydroxyethyl acrylate (PDM) in aqueous phase. Biodegradation of PDM was investigated in activated sludge systems, and the effects of the solution pH, mixed liquid suspended solids (MLSS), salinity, co-substrate, and initial substrate concentration, were studied. The biodegradation process was well-described with the Monod model and the values of the kinetics parameters vmax, ks were 0.05 h-1 and 333 mg/L. The optimal biodegradation conditions in the experimental range were determined to be: pH = 7.0, 0%-0.01% (w/v) NaCl, 4000 mg/L of MLSS, and 500 mg/L of glucose as co-substrate. FT-IR analysis indicated that PDM molecules biodegradation partly. The microbial community structures and dehydrogenase activity analysis revealed that PDM showed some toxicity to microorganisms in activated sludge. The effects of several parameters, including the pH and chemical doses, were investigated for removing PDM in Fenton oxidation process. The optimal Fenton oxidation process conditions in the experimental range were pH = 2.0, Fe2+ concentration of 40 mg/L, and H2O2 dosage of 23 mL/L. PDM was treated by biodegradation and subsequent Fenton oxidation under the optimal operating conditions. The removal efficiency was 44.5% after the biodegradation process and further increased to 85.5% after Fenton oxidation. The combined process was revealed to be a promising solution for achieving effective and economical removal of PDM.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Polietilenos/análise , Compostos de Amônio Quaternário/análise , Esgotos , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental , Cinética , Oxirredução , Esgotos/química , Esgotos/microbiologia
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