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1.
Int J Biol Macromol ; 273(Pt 2): 132945, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38851614

RESUMEN

The extensive utilization of non-biodegradable plastic agricultural mulch in the past few decades has resulted in severe environmental pollution and a decline in soil fertility. The present study involves the fabrication of environmentally friendly paper-based mulch with dual functionality, incorporating agrochemicals and heavy metal ligands, through a sustainable papermaking/coating technique. The functional paper-based mulch consists of a cellulose fiber web incorporated with Emamectin Benzoate (EB)@ Aminated sodium lignosulfonate (ASL). The spherical microcapsules loaded with the pesticide EB exhibited an optimal core-shell structure for enhanced protection and controlled release of the photosensitizer EB (Sustained release >75 % in 50 h). Meanwhile, the ASL, enriched with metal chelating groups (-COOH, -OH, and -NH2, etc.), served as a stabilizing agent for heavy metal ions, enhancing soil remediation efficiency. The performance of paper-based mulch was enhanced by the application of a hydrophobic layer composed of natural chitosan/carnauba wax, resulting in exceptional characteristics such as superior tensile strength, hydrophobicity, heat insulation, moisture retention, as well as compostability and biodegradability (biodegradation >80 % after 70 days). This study developed a revolutionary lignocellulosic eco-friendly mulch that enables controlled agrochemical release and soil heavy metal remediation, leading to a superior substitute to conventional and non-biodegradable plastic mulch used in agriculture.


Asunto(s)
Lignina , Metales Pesados , Plaguicidas , Metales Pesados/química , Lignina/química , Lignina/análogos & derivados , Plaguicidas/química , Preparaciones de Acción Retardada , Plásticos/química , Contaminantes del Suelo/química , Agricultura/métodos , Quitosano/química , Fármacos Fotosensibilizantes/química , Biodegradación Ambiental , Suelo/química
2.
J Chem Phys ; 160(4)2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38258919

RESUMEN

Previous studies have shown that NaB6, KB6, and RbB6 adopting Pm3̄m are superconductors with a relatively high Tc under ambient conditions. In this paper, we conducted systematic structural and related properties research on CsB6 through a genetic evolution algorithm and total energy calculations based on density functional theory between 0 and 20 GPa. Our results reveal a cubic Pm3̄m CsB6, which is dynamically stable under the pressures we studied. We systematically calculated the formation enthalpies, electronic properties, and superconducting properties of Pm3̄m MB6 (M = Na, K, Rb, Cs). They all exhibit metallic features, and boron has high contributions to band structures, density of states, and electron-phonon coupling (EPC). The calculated results about the Helmholtz free energy difference of Pm3̄m CsB6 at 0, 10, and 20 GPa indicate that it is stable upon chemical decomposition (decomposition to simple substances Cs and B) from 0 to 400 K. The phonon density of states indicates that boron atoms occupy the high frequency area. The EPC results show that Pm3̄m CsB6 is a superconductor with Tc = 11.7 K at 0 GPa, close to NaB6 (13.1 K), KB6 (11.7 K), and RbB6 (11.3 K) at 0 GPa in our work, which indicates that boron atoms play an essential role in superconductivity: vibrations of B6 regular octagons lead to the high Tc of Pm3̄m MB6. Our work about Pm3̄m hexaborides provides a supplementary study on the borides of the group IA elements (without Fr and Li) and has an important guiding significance for the experimental synthesis of CsB6.

3.
Int J Biol Macromol ; 255: 128347, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37995788

RESUMEN

Extensively used agricultural mulch fabricated from nonbiodegradable polyolefin plastic causes tremendous environmental pollution. In this work, a paper-based mulch, composed of the cellulose fiber networks incorporated with Emamectin benzoate (EB)@sodium lignosulfonate (SL), has been developed with facile papermaking/coating methods. The spherical microcapsule loaded with pesticide EB has a desirable core-shell structure for better protection and sustained release of photosensitive EB. The loading rate and encapsulation efficiency reached 78.5 % and 52.3 %, respectively. Furthermore, microcapsules exhibited excellent slow-release behavior and resistance to photolysis. Natural carnauba wax was coated on the surface of the paper-based mulch to form a hydrophobic layer and increase the physical intertwinement of fibers in the mulch, thereby exhibiting superior performance, such as enhanced tensile strength, excellent hydrophobicity, high air permeability, and high light transmittance at reasonable level. Moreover, unlike conventional polyethylene mulch film, the functionalized paper-based mulch almost completely biodegraded after 75 days in the soil. Thus, multifunctional, eco-friendly mulch from lignocellulose is an innovative approach to obtaining the sustained release of agrochemicals, and it provides an excellent alternative to conventional agricultural plastic mulch.


Asunto(s)
Plaguicidas , Plaguicidas/análisis , Preparaciones de Acción Retardada , Agricultura/métodos , Suelo/química , Cápsulas
4.
Environ Pollut ; 335: 122351, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37567404

RESUMEN

The issue of mercury pollution in environmental remediation has garnered significant attention due to its severe health hazards to humans. Various strategies have been devised to mitigate the impact of toxic mercury ions, including coagulation, ion exchange, adsorption, membrane technology, and electrochemical treatment. Among these approaches, adsorption has emerged as an efficient and widely employed method for the uptake of low concentrations of mercury ions. It offers convenient operation, high removal efficiency, and facile regeneration of the adsorbent. Wood, being the most abundant renewable and sustainable bioresource, has garnered attention as a promising material for treating heavy metal wastewater. This is attributed to its unique physical and chemical characteristics, encompassing hierarchical pores, aligned channels, active functional groups, biodegradability, and cost-effectiveness. However, a comprehensive examination of the cutting-edge applications of wood and wood-derived biopolymers in the detection and removal of mercury ions from wastewater has yet to be undertaken. Consequently, this article presents a chronological overview of recent advancements in materials and structures derived from bulk wood and its constituents, including cellulose, lignin, hemicellulose, and tannin, with a specific focus on their utility in detecting and eliminating mercury from water sources. Subsequently, the most promising techniques and strategies involving wood and wood-derived biopolymers in addressing the predicament of mercury pollution are explored. Furthermore, this piece offers insights into the existing challenges and future prospects concerning environmentally friendly materials derived from wood, aiming to foster the development of cost-effective mercury adsorbents and detection devices.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Humanos , Adsorción , Biopolímeros , Iones/análisis , Mercurio/análisis , Aguas Residuales , Agua/análisis , Contaminantes Químicos del Agua/análisis , Madera/química
5.
Zhonghua Wai Ke Za Zhi ; 49(1): 57-60, 2011 Jan 01.
Artículo en Chino | MEDLINE | ID: mdl-21418840

RESUMEN

OBJECTIVE: To summarize the prevention and treatment experience of deep vein thrombosis in patients with abdominal tumors after standardized resection and lymph node dissection, and to investigate a standard therapeutic measure of thrombosis prevention in these patients. METHODS: The clinical data of 548 patients who received radical operation and standardized lymph node dissection for abdominal tumors from January 2007 to April 2010 were analyzed retrospectively. According to different therapeutic scheme and time, the patients were divided into three groups: Group 1 included 163 cases from January 2007 to March 2008 were treated with compound Danshen injection 0.2 g and low molecular weight dextran 500 ml on the same day of surgery for 7 days; Group 2 included 149 cases from April 2008 to March 2009 were treated with the same regimen as that in Group 1 plus low molecular heparin 40 mg on the same day of surgery for 7 days; Group 3 included 236 cases from April 2009 to April 2010 were treated with the same regimen as that in Group 1 plus low molecular heparin on the third day of surgery for 7 days. The treatment effects and the complications in the three groups were analyzed and compared. RESULTS: Sixty-four (39.3%) cases were D-Dimer positive and 15 (9.2%) cases were DVT positive under color Doppler ultrasound examination in Group 1; and those were 38 (25.5%) and 3 (2.0%) in Group 2; and 62 (26.3%) and 6(2.5%) in Group 3. Overall observation, the incidences of thrombosis in Group 2 and 3 were obviously lower than that of Group 1, but there was no significant difference between Group 2 and 3. Earlier use of low molecular heparin would lead to some complications. CONCLUSIONS: It brings better effects in thrombosis prevention by using compound Danshen injection and low molecular weight dextran on the day of surgery, with low molecular heparin on the third day of surgery.


Asunto(s)
Complicaciones Posoperatorias , Trombosis de la Vena/prevención & control , Trombosis de la Vena/terapia , Neoplasias Abdominales/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Trombosis de la Vena/etiología
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