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Low-dimensional organic-inorganic hybrid metal halide materials have been extensively studied due to their excellent optoelectronic performances. Herein, by using the facile wet-chemistry method, we designed one new hybrid cadmium bromide of (H3AEP)2CdBr6·2Br based on discrete octahedral [CdBr6]4- units. Remarkably, the bulk crystal of (H3AEP)2CdBr6·2Br exhibits strong broadband orange-red light emission from the radiative recombination of self-trapped excitons (STEs) with a high photoluminescence quantum yield (PLQY) of 9%. Benefiting from the highly efficient luminescent performance, this 0D cadmium perovskite can be utilized as an excellent down-conversion red phosphor to assemble a white light-emitting diode, and a high color rendering index (CRI) of 93 is realized. As far as we know, this is the first orange-red light-emitting hybrid cadmium perovskite which promotes the full-color display in this system.
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In this paper, we describe Ixeridiumnujiangense, a novel species identified in southwestern Yunnan, China. Two populations have been found along the riverbanks of the Nujiang River in Yongde and Zhenkang Counties. Morphologically, I.nujiangense is most similar to the recently described I.malingheense, but it can be readily distinguished by its mostly divided basal leaves, narrower non-clasping cauline leaves, notably shorter corolla tube, pale brown anthers, and considerably longer beak of achenes.
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In this paper, we describe a new species, Melanoserispenghuana, from Mt. Jiaozi Xueshan located in North-central Yunnan, China. Despite its morphological similarities to M.likiangensis, M.penghuana exhibits distinct differences in leaf texture, shape of terminal lobes, indumentum of leaves, peduncles, and involucres, as well as the length of the achenes. Additionally, the conservation status of this species is classified as Vulnerable through data analysis from two field surveys.
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Melanoseriskangdingensis, a new species native to western Sichuan, China, is firstly described and illustrated, and its conservation status is also assessed. It bears resemblance to M.macrantha and M.bracteata in terms of morphology; however, there are distinguishing characteristics in terms of their leaf structure, presence of bracts, hairiness of involucre, number of florets, and length of both stamen tube and achene's beak.
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High-risk human papillomavirus (HR-HPV) infection is a major cause of infection-related cancer worldwide. 3101 HR-HPV-positive females were retrospectively analyzed and grouped using the cervical cytological screening (ThinPrep cytological test, TCT) evaluations combined with colposcopy. The HPV16 infection rate is the highest in all groups. HPV16 was the most frequent in each group, with significant differences between the four groups (χ2 = 23.41, P = 0.0001). The distribution of HPV16 and HPV33 correlated with the pathologic stage in each group. The mixed infection rate of mRNA testing differs significantly between groups (P < 0.01, χ2 = 17.44, P = 0.002). HR-HPV infection duration of less than six months accounted for 87.65%, 6 and 12 months of persistent infection (28.28%), and more than one year of continuous infection accounted for only 16.48%. The top three HPV types in a group with a duration of more than 12 months were HPV52 (3.03%), HPV16 (2.55%), and HPV39 (1.58%). The least clearance types were HPV39 (63.48%), 56 (69.54%), and 52 (71.44%) more than 12 months. This study revealed the region's primary pathogenic subtypes on different cervical lesions and provided the basis for diagnosing and treating HPV infection.
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Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Humanos , Displasia del Cuello del Útero/diagnóstico , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/patología , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/epidemiología , Estudios Retrospectivos , Detección Precoz del Cáncer , Papillomavirus Humano 18/genética , Papillomaviridae/genética , Papillomavirus Humano 16/genética , GenotipoRESUMEN
Preferential removal of phosphate from aqueous was conducted by a novel biomass-based nanocomposite (EP-N+-Zr) with encapsulated hydrous zirconium oxide, and the biopolymer EP-N+-Zr features were described. EP-N+-Zr exhibited high selective sequestration toward phosphate when humic acid or other competing anions (Cl-, SO42-, NO3-, ClO4-) coexisted at relatively high levels. Such excellent performance of EP-N+-Zr was attributed to its specific two site structures; the embedded HZO nanoparticles and quaternary ammonia groups [N+(CH2CH3)3Cl-] bonded inside the biomass-Enteromorpha prolifera, which facilitated preferable capture towards phosphate through specific affinity and nonspecific preconcentration of phosphate ions on the basis of the ion exchange, respectively. The maximum adsorption capacity of phosphate (20 °C) as calculated by Langmuir model was 88.5 mg(P)/g. Regeneration tests showed that EP-N+-Zr could be recycled at least five times without noticeable capacity losses using binary NaOH-NaCl as eluent.
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Nanopartículas , Contaminantes Químicos del Agua , Adsorción , Biopolímeros , Concentración de Iones de Hidrógeno , Cinética , Fosfatos , Contaminantes Químicos del Agua/análisis , CirconioRESUMEN
A cellulose-rich biomass was modified as a new amphoteric sorbent to eliminate toxic Cu(II) and Cr(VI) from wastewater. The product (WSCA, which stands for modified wheat straw containing both cationic and anionic characters) presents high sorption capacities for the two ions which was evidenced by the comparison with unmodified wheat and other similar samples. Kinetic data and sorption equilibrium isotherms were conducted in batch process. The sorption kinetic analysis revealed that sorption of Cu(II) and Cr(VI) followed the pseudo second-order model well during the whole sorption process. The linear Langmuir isotherm model could perfectly describe the equilibrium data for Cu(II), while the sorption data of Cr(VI) were well fitted by the Freundlich. Results of the static test illustrated the complicated interactions between Cr(VI)/Cu(II) and WSCA including complexation and/or electrostatic attraction mechanisms.
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Celulosa/química , Cromo/aislamiento & purificación , Cobre/aislamiento & purificación , Aguas Residuales/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Biomasa , Modelos Químicos , Electricidad Estática , Purificación del Agua/métodosRESUMEN
The nitrate removal process was evaluated using a fixed-bed column packed with amine-crosslinked wheat straw (AC-WS). Column sorption and desorption characteristics of nitrate were studied extensively. Solid-state (13)C NMR and zeta potential analysis validated the existence of crosslinked amine groups in AC-WS. Raman shift of the nitrate peaks suggested the electrostatic attraction between the adsorbed ions and positively charged amine sites. The column sorption capacity (q(ed)) of the AC-WS for nitrate was 87.27 mg g(-1) in comparison with the raw WS of 0.57 mg g(-1). Nitrate sorption in column was affected by bed height, influent nitrate concentration, flow rate and pH, and of all these, influent pH demonstrated an essential effect on the performance of the column. In addition, desorption and dynamic elution tests were repeated for several cycles, with high desorption rate and slight losses in its initial column sorption capacity.
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Aminas/química , Nitratos/química , Triticum/química , Adsorción , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Espectrometría RamanRESUMEN
A new cellulosic amine-crosslinked copolymer was prepared after the amination reaction with cotton stalk peel (CSP). The physicochemical characteristics of amine-crosslinked cotton stalk peel (AC-CSP) and raw CSP were determined after the surface analysis (including specific surface area, micropore volume and SEM), zeta potential analysis and spectrum analysis (FTIR and Raman spectrum). The sorption properties of AC-CSP for Cr(VI) were evaluated in the static, column sorption and desorption tests. The surface characteristics indicated the absence of porous adsorption in the potential Cr(VI) sorption mechanism. Zeta potential and spectrum analysis of AC-CSP illustrated the involvement of amine groups in the Cr(VI) sorption process. The sorption capacity of AC-CSP for Cr(VI) was 129.0mg/g as comparison with 14.8 mg/g of raw CSP. Flow rate and influent Cr(VI) concentration were demonstrated as two influencial factors in the column sorption tests. NaCl was used as the eluent, and the desorption efficiencies during three successive cycles were 75.9%, 69.8% and 64.3%, respectively. In addition, the results of the static, column sorption and desorption tests illustrated the complicated interactions between Cr(VI) and AC-CSP including complexation and ion exchange mechanisms.
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Aminas/química , Celulosa/química , Cromo/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Reactivos de Enlaces Cruzados , Intercambio Iónico , Cloruro de Sodio , Soluciones , AguaRESUMEN
To develop the agricultural by-product adsorbent that possesses anionic exchangeable function, the performance of a new anion exchanger prepared from wheat straw (WS) was evaluated in this study. Wheat straw anion exchanger (WS-AE) was prepared by the grafting of aminated intermediate onto WS. Results indicate that reaction time and temperature in the chemical modification process both affected the preparation of aminated intermediate and WS-AE. FTIR, nitrogen content, solid-state (13)C NMR and zeta potential data validated the existence of grafted amine group in the structure of WS-AE. The maximum sorption capacities of WS-AE for nitrate and phosphate were approximately 52.8 and 45.7mgg(-1), respectively, which shows higher maximum capacity for phosphate and a similar capacity for nitrate in comparison with commercial anion resins. Regeneration studies and column adsorption tests were performed, and the excellent regeneration and column adsorption capacities provided strong evidence of the potential of WS-AE for the technological applications of phosphate and nitrate removal from aqueous solutions.
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Residuos Industriales/prevención & control , Nitratos/aislamiento & purificación , Fosfatos/aislamiento & purificación , Triticum/química , Ultrafiltración/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Absorción , Agricultura/métodos , Aniones , Cromatografía por Intercambio Iónico/métodos , Ensayo de Materiales , Componentes Aéreos de las Plantas/químicaRESUMEN
Removal of Acid Red 73 (AR 73) and Reactive Red 24 (RR 24) onto modified wheat straw (MWS) from aqueous solutions was investigated. Sorption experiments were carried out as function of MWS dosage, contact time, initial concentration, pH and temperature. Characterizations of MWS were measured and a mass of amine groups were observed in the framework of MWS. The equilibrium sorption data were well represented by the Langmuir isotherm equation, and the calculated thermodynamic parameters indicated a spontaneous and endothermic nature for sorption process. It was shown that pseudo-second-order kinetic equation could best describe the adsorption kinetics. More over, the high maximum sorption capacity (q(e max), 714.3 mg g(-1) for AR 73 and 285.7 mg g(-1) for RR 24) and low cost (1.24 US$ kg(-1)) of MWS provided strong evidence of the potential of MWS for the technological applications of anionic dyes removal from aqueous solutions.