RESUMEN
Rapid development of society and the improvement of people's living standards have stimulated people's keen interest in fashion clothing. This trend has led to the acceleration of new product innovation and the shortening of the lifespan for cotton fabrics, which has resulting in the accumulation of waste cotton textiles. Although cotton fibers can be degraded naturally, direct disposal not only causes a serious resource waste, but also brings serious environmental problems. Hence, it is significant to explore a cleaner and greener waste textile treatment method in the context of green and sustainable development. To realize the high-value utilization of cellulose II aerogel derived from waste cotton products, great efforts have been made and considerable progress has been achieved in the past few decades. However, few reviews systematically summarize the research progress and future challenges of preparing high-value-added regenerated cellulose aerogels via dissolving cotton and other cellulose wastes. Therefore, this article reviews the regenerated cellulose aerogels obtained through solvent methods, summarizes their structure, preparation strategies and application, aimed to promote the development of the waste textile industry and contributed to the realization of carbon neutrality.
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Celulosa , Fibra de Algodón , Geles , Textiles , Celulosa/química , Fibra de Algodón/análisis , Geles/químicaRESUMEN
Regenerated cellulose fibers has attracted increasing attention for high-grade textile raw materials and industrial textiles, but the low mechanical property caused by differences in regenerated raw materials and production levels limits its commercial application in the product diversity. Herein, we proposed a novel triple-crosslinking strategy by coupling with hydrogen bonds, chemical crosslinking, and internal mineralization from multiple pulsed vapor phase infiltration (MPI) to improve the mechanical performance of regenerated cellulose fibers. A binary solvent composed of ionic liquid (IL) and dimethyl sulfoxide (DMSO) is used to dissolve waste cotton textile and then wet spinning. Dual-crosslinking is firstly achieved by coupling glutaraldehyde (GA) and cellulose reaction. Subsequently, a metal oxide is intentionally infiltrated into inner cellulosic through MPI technology to form a third form of crosslinking, accompanied by the ultra-thin metal oxide nano-layer onto the surface of regenerated cellulose fibers. Results showed that the triple-crosslinking strategy has increased the tensile stress of the fiber by 43.57 % to 287.03 MPa. In all, triple-crosslinking strategy provides a theoretical basis and technical approach for the reinforcement of weak fibers in waste cotton recycling, which is expected to accelerate the development of the waste textile recycling industry and promote of the added-value of regenerated products.
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Fibra de Algodón , Textiles , Celulosa/química , ÓxidosRESUMEN
A series of organoaluminium imino-amido complexes of the type {[ArNC(Me2)C(Me)[double bond, length as m-dash]NAr]AlMe2} (Ar = 2,6-iPr2C6H3 (1), Ar = 2,6-Et2C6H3 (2); Ar = 2,6-Me2C6H3 (3) have been prepared via reaction of AlR3 and the respective α-diimine. Similar reaction of the bis(α-diimine) [ArN[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]N-]2 (Ar = 2,6-iPr2C6H3) with AlMe3 afforded the bimetallic complex [ArN-C(Me)2C(Me)[double bond, length as m-dash]NAlMe2]2 (4), whilst reaction of the acetyl-imino compound [O[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]NAr] (Ar = 2,6-Et2C6H3) with AlMe3 afforded the bimetallic complex {[OCMe2CH(Me)[double bond, length as m-dash]NAr]AlMe2}2 (5). In related organozinc chemistry, we have isolated {[ArNC(Me)(Et)C(Me)[double bond, length as m-dash]NAr]ZnEt} (Ar = 2,6-iPr2C6H3, 6) and the trinuclear complex {[ArN[double bond, length as m-dash]C(Me)COCHCO(Me)C(Me)[double bond, length as m-dash]NAr][OCH(Me)C(Me)[double bond, length as m-dash]NAr](ZnEt)3} (Ar = 2,6-iPr2C6H3, 7) from reactions of ZnEt2 with ArN[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]NAr or [O[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]NAr], respectively. Reaction of the bis(α-diimine), LiPr-N2-ArCH2Ar-N2, derived from 4,4'-methylenebis(2,6-diisopropylaniline), with ZnCl2 affords [LiPr-N2-ArCH2Ar-N2(ZnCl2)2] (8). The molecular structures of complexes 1-8 are reported. Preliminary results of the ability of 1-8, along with the previously reported metal-metal bonded complex {[ArN[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]NAr]Al(THF)}2 (9), to act as catalysts for the ring opening polymerization (ROP) of the cyclic esters ε-caprolactone (ε-CL), δ-valerolactone (δ-VL) and rac-lactide (r-LA) are presented. For ε-CL and δ-VL, best results were obtained using the metal-metal bonded complex 9. For r-LA, the Al-based systems exhibited moderate activity affording only liquid oligomers, whilst the Zn-based systems performed better affording at 80 °C isotactic PLA with Mnca. 10 kDa with conversions of up to 66%. The co-polymerization of ε-CL with δ-VL was also examined, and differing preferences were noted for monomer incorporation.
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BACKGROUND: A GWAS found that the single-nucleotide polymorphism rs11833579 near the NINJ2 gene on chromosome 12p13 was associated with an increased risk of ischemic stroke in Caucasians in 2009. Several studies have been carried out to explore the association between this SNP and ischemic stroke in Asians, but published results were contradictory. In the present study, we performed a meta-analysis to further evaluate this association in the Asian population. METHODS: All relevant articles were retrieved from the databases of PubMed, EMBASE, Chinese Biomedical Literature Database, CNKI, CQVIP, and WANFANG Database from the establishment date to February 2014. Statistical analyses were performed by using Stata 11. The pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were used to assess the strength of the association. Possible publication bias was checked by funnel plots, Begg's test and Egger's test. RESULTS: Eleven studies were eligible for meta-analysis including 9358 cases and 8936 controls. Overall, there were no significant associations between rs11833579 and ischemic stroke under the allelic (OR=0.963, 95% CI: 0.850-1.092, p=0.559), dominant (OR=0.946, 95% CI: 0.778-1.150, p=0.580), recessive (OR=0.993, 95% CI: 0.914-1.078, p=0.868), and homozygote (OR=0.968, 95% CI: 0.796-1.177, p=0.744) genetic models in the Asian population. Further, we found no evidence of association of rs11833579 with large artery atherosclerosis (LAA) or small-artery occlusion (SAO) stroke in all genetic models. The results of the subgroup analysis for Chinese population and Japanese population were consistent with that of the overall study. CONCLUSIONS: Our meta-analysis shows that SNP rs11833579 is not related to ischemic stroke in the Asian population.
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Cromosomas Humanos Par 12/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Accidente Cerebrovascular/genética , Pueblo Asiatico/genética , Moléculas de Adhesión Celular Neuronal/genética , Bases de Datos Factuales/estadística & datos numéricos , Femenino , Estudios de Asociación Genética , Humanos , Isquemia/complicaciones , Masculino , Sesgo de Publicación , Accidente Cerebrovascular/etiologíaRESUMEN
BACKGROUND AND OBJECTIVE: Mediastinal lymphoma or right upper lung cancer is a common cause of superior vena cava obstruction syndrome (SVCOS). Endobronchial ultrasound-guided needle aspiration (EBUS-TBNA) biopsy is applied for the diagnosis of mediastinal mass disease. The aim of this study is to explore the safety and feasibility of EBUS-TBNA biopsy under general anesthesia for the clinical diagnosis of SVCOS. METHODS: Twenty-five cases of SVCOS received EBUS-TBNA under general anesthesia between June 2012 and June 2013. The group consisted of 16 male and 9 female patients aged 33 years to 76 years, with a median age of 62.5. RESULTS: Twenty-four cases were confirmed to be of malignant pathology, and one case failed to yield a clear pathological diagnosis. No patient experienced any complications related to the operation, such as heavy bleeding and pneumothorax. CONCLUSIONS: For patients presenting with SVCOS, EBUS-TBNA under general anesthesia is a safe and reliable inspection method of high diagnostic yield. This method can be used for routine examination when other means cannot obtain clear pathological diagnosis.