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1.
J Microbiol Biotechnol ; 34(6): 1197-1205, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38693049

RESUMEN

Filamentous fungi are important cell factories for the production of high-value enzymes and chemicals for the food, chemical, and pharmaceutical industries. Under submerged fermentation, filamentous fungi exhibit diverse fungal morphologies that are influenced by environmental factors, which in turn affect the rheological properties and mass transfer of the fermentation system, and ultimately the synthesis of products. In this review, we first summarize the mechanisms of mycelial morphogenesis and then provide an overview of current developments in methods and strategies for morphological regulation, including physicochemical and metabolic engineering approaches. We also anticipate that rapid developments in synthetic biology and genetic manipulation tools will accelerate morphological engineering in the future.


Asunto(s)
Fermentación , Hongos , Ingeniería Metabólica , Hongos/genética , Hongos/metabolismo , Ingeniería Metabólica/métodos , Biología Sintética/métodos , Morfogénesis , Micelio/crecimiento & desarrollo , Micelio/metabolismo
2.
Toxics ; 12(5)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38787141

RESUMEN

Microbial scale-up cultivation is the first step to bioremediating cadmium (Cd)-contaminated soils at the industrial scale. However, the changes in the microbial community as the bioreactor volume expands and their associations with soil Cd removal remain unclear. Herein, a six-stage scale-up cultivation process of mixotrophic acidophiles was conducted, scaling from 0.1 L to 10 m3, to remediate Cd-contaminated soils. The findings showed that bioreactor expansion led to a delay in sulfur and glucose oxidations, resulting in a reduced decline in solution pH and cell density. There were minimal differences observed in bacterial alpha-diversity and community structure as the bioreactor volume increased, except for the 10 m3 scale. However, bioreactor expansion decreased fungal alpha-diversity, changed the community structure, and simplified fungal community compositions. At the family level, Acidithiobacillaceae and Debaryomycetaceae dominated the bacterial and fungal communities throughout the scale-up process, respectively. Correlation analysis indicated that the indirect effect of mixotrophic acidophiles played a significant role in soil Cd removal. Bacterial community shifts, driven by changes in bioreactor volume, decreased the pH value through sulfur oxidation, thereby indirectly enhancing Cd removal efficiency. This study will contribute to the potential industrial application of mixotrophic acidophiles in bioremediating Cd-contaminated soils.

3.
Plants (Basel) ; 13(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38475438

RESUMEN

The vegetable plug seedling plays an important role in improving vegetable production. The process of plug seedling contributes to high-quality vegetable seedlings. The substrate composition and chemical fertilizer are widely studied to promote seedling growth. However, little is known about the effect of beneficial bacteria in the rhizosphere microbial community and vegetables' growth during plug seedling. The use of beneficial microbes to promote vegetable seedling growth is of great potential. In this study, we showed that the Serratia marcescens strain LYGN1 enhanced the growth of cucumber and pepper seedlings in plug seedling cultivation. The treatment with LYGN1 significantly increased the biomass and the growth-related index of cucumber and pepper, improving the seedling quality index. Specifically, LYGN1 also improved the cucumber and pepper root system architecture and increased the root diameter. We applied high-throughput sequencing to analyze the microbial community of the seedlings' rhizosphere, which showed LYGN1 to significantly change the composition and structure of the cucumber and pepper rhizosphere microbial communities. The correlation analysis showed that the Abditibacteriota and Bdellovibrionota had positive effects on seedling growth. The findings of this study provide evidence for the effects of Serratia marcescens LYGN1 on the cucumber and pepper rhizosphere microbial communities, which also promoted seedling quality in plug seedling cultivation.

4.
Head Face Med ; 19(1): 9, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36922821

RESUMEN

OBJECTIVE: To investigate the clinical observation of autologous platelet-rich fibrin (PRF) assisting the revascularization of mature permanent teeth. METHODS: Twenty patients with mature permanent teeth were divided into experimental group and control group. The control group was treated with classic revascularization, and the experimental group was treated with PRF-assisted mature permanent tooth revascularization. RESULTS: After treatment, the total effective rate of the experimental group (100.00%) was higher than that of the control group (50.00%); the thickness of the root canal wall of the experimental group was higher than that of the control group, and the crown root length was lower than that of the control group; The bite degree, chewing function, color, overall aesthetic score, and satisfaction rate of the patients were higher, and the difference was statistically significant (P < 0.05). CONCLUSION: Autologous PRF assists in revascularization of mature permanent teeth, which can achieve ideal results, and promote pulp regeneration.


Asunto(s)
Fibrina Rica en Plaquetas , Humanos , Pulpa Dental , Regeneración , Estética Dental , Tratamiento del Conducto Radicular/métodos
5.
Sensors (Basel) ; 22(15)2022 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-35898012

RESUMEN

Humor is a special human expression style, an important "lubricant" for daily communication for people; people can convey emotional messages that are not easily expressed through humor. At present, artificial intelligence is one of the popular research domains; "discourse understanding" is also an important research direction, and how to make computers recognize and understand humorous expressions similar to humans has become one of the popular research domains for natural language processing researchers. In this paper, a humor recognition model (MLSN) based on current humor theory and popular deep learning techniques is proposed for the humor recognition task. The model automatically identifies whether a sentence contains humor expression by capturing the inconsistency, phonetic features, and ambiguity of a joke as semantic features. The model was experimented on three publicly available wisecrack datasets and compared with state-of-the-art language models, and the results demonstrate that the proposed model has better humor recognition accuracy and can contribute to the research on discourse understanding.


Asunto(s)
Inteligencia Artificial , Web Semántica , Humanos , Lenguaje , Procesamiento de Lenguaje Natural , Semántica
6.
Chemosphere ; 305: 135393, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35724719

RESUMEN

A novel nanocomposite, named as nZVI@LH, was prepared by nanoscale zero-valent iron (nZVI) supported on lignin hydrogel and was used in the remediation of Cr(VI)-contaminated soil collected from an industrial site. Meanwhile, scanning electron microscopy with energy dispersive X-ray (SEM-EDX) and X-ray diffractometry (XRD) results determined that nZVI nanoparticles disperse uniformly on hydrogel. After the 14 days remediation, the immobilization efficiency of Cr(VI) could reach over 87% in the treatment of 3% (w/w%) nZVI@LH and 26% in the treatment of bare-nZVI. Leaching experiment results showed that the treatment group with 3% (w/w%) nZVI@LH was up to the national leaching toxicity identification standard, and there was no threat in simulation of acid rain over the long term. The water-soluble (WS) fraction in 3# nZVI@LH treatment decreased 31.1%, while the Fe-Mn oxide bound (OX) fraction and organic matter-bound (OM) fraction increased 10.9% and 13.4%, respectively. Moreover, nZVI@LH had limited impact on soil properties and the capability to immobilize Cr over a long period exposure to acid rain. This work prove that nZVI@LH has the potential to remediate Cr contaminated soil. Furthermore, details of possible mechanistic insight into the Cr remediation were carefully discussed.


Asunto(s)
Lluvia Ácida , Restauración y Remediación Ambiental , Contaminantes del Suelo , Contaminantes Químicos del Agua , Cromo/análisis , Hidrogeles , Hierro , Lignina , Suelo , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis
7.
Aging (Albany NY) ; 12(13): 12684-12702, 2020 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-32629426

RESUMEN

Long non-coding RNAs (lncRNAs) have been largely reported to contribute to the development and progression of abdominal aortic aneurysm (AAA), a common vascular degenerative disease. The present study was set out with the aim to investigate the possible role of lncRNA Sox2ot in the development of AAA. In this study, we found that lncRNA Sox2ot and early growth response factor-1 (Egr1) were highly expressed, while microRNA (miR)-145 was poorly expressed in Ang II-induced AAA mice and oxidative stress-provoked vascular smooth muscle cell (VSMC) model. Egr1 was a potential target gene of miR-145, and lncRNA Sox2ot could competitively bind to miR-145 to upregulate Egr1 expression. Overexpression of miR-145-5p was found to attenuate oxidative stress and inflammation by inhibiting Egr1 both in vivo and in vitro, which was counteracted by lncRNA Sox2ot. Taken together, the present study provides evidence that downregulation of lncRNA Sox2ot suppressed the expression of Egr1 through regulating miR-145, thus inhibiting the development of AAA, highlighting a theoretical basis for AAA treatment.


Asunto(s)
Aneurisma de la Aorta Abdominal/metabolismo , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , MicroARNs/metabolismo , Estrés Oxidativo/genética , ARN Largo no Codificante , Animales , Aorta Abdominal/citología , Aorta Abdominal/metabolismo , Apolipoproteínas E/genética , Células Cultivadas , Regulación hacia Abajo , Proteína 1 de la Respuesta de Crecimiento Precoz/antagonistas & inhibidores , Silenciador del Gen , Inflamación , Ratones , Ratones Noqueados , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Estrés Oxidativo/fisiología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
8.
Bioresour Technol ; 263: 350-357, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29772499

RESUMEN

In this study, nitrogen was used to replace oxygen through biomass N-enriched pyrolysis in a fixed-bed reactor to obtain N-containing chemicals and N-doped biochar. Influence of NH3 concentration on the formation mechanism of N-species and electrochemical performance of N-doped biochar was investigated in depth. Results showed that increasing NH3 concentration promoted bio-oil and gas generation, and increased H2, CH4 and CO yield at the diminishing of CO2. Simultaneously, bio-oil showed lower oxygen content with non-methoxy phenols and N-heterocyclics as the main components, and the maximums were 57.73% and 16.21% at 80 vol% NH3 concentration, respectively. With regard to solid N-doped biochar, nitrogen content (4.85 wt%), N-containing groups and specific surface area (369.59 m2/g) increased greatly, and excellent electrochemical property (120 F/g) was shown with NH3 concentration increasing. However, NH3 conversion efficiency decreased gradually with NH3 increasing, and 40 vol% may be the optimum NH3 concentration for biomass N-enriched pyrolysis.


Asunto(s)
Biocombustibles , Nitrógeno , Biomasa , Carbón Orgánico , Calor
9.
Exp Ther Med ; 14(6): 5339-5344, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29285061

RESUMEN

The embryological stages of palatal shelf elongation and elevation, mainly induced by the proliferation and extracellular matrix secretion of embryonic palatal mesenchymal (MEPM) cells, are essential for normal palatal development. Wingless-related MMTV integration site gene family (Wnt) signaling pathways serve key roles in craniofacial development and palate formation. Recent studies have indicated that Wnt6 participates in embryonic development of the palate, though its exact role in palate development remains unclear. In the present study, to investigate the role of Wnt6 during the stages of palatal shelves elongation and elevation, mouse MEPM cells were cultured from dissected palatal shelves at embryonic day 13.5. Results of an MTT assay and flow cytometric analysis demonstrated that treatment with recombinant Wnt6 increased the viability of MEPM cells (P<0.01) and the proportion of cells in the S and G2/M phases (P<0.01). Meanwhile, Wnt6 activated the ß-catenin signaling pathway as indicated by the dual luciferase assay result, and blockade of the WNT/ß-catenin pathway reduced the cytoactivity of Wnt6 in MEPM cells (P<0.01). Collectively, these findings indicate that Wnt6 promotes the vitality of MEPM cells by increasing the S + G2/M-phase cell population, potentially through activation of the ß-catenin pathway during palatal shelf elongation and elevation.

10.
Environ Sci Pollut Res Int ; 24(29): 23236-23249, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28831706

RESUMEN

Round-Bohai Bay (RBB)-Region is an important crop production area in China, where vegetables are mainly produced in solar greenhouses. However, excessive fertilization and monoculture have caused serious deterioration of soil quality in this region. Soil microbial communities play pivotal roles in many ecosystem processes and are recognized as integrative components of soil quality. Therefore, in this study, we investigated bacterial and fungal diversity in solar greenhouse soils covering a wide range of cultivation year (CY) and sampling site (SS), by using pyrosequencing technology. Surprisingly, CY and SS had little influence on bacterial and fungal relative abundance and diversity. However, environmental factors (EF) and soil available potassium (K) in particular made a significant contribution to the variation of soil bacterial and fungal communities. Specifically, K showed significant (P < 0.05) correlations with dominant bacterial phyla Bacteroidetes, Acidobacteria, Chloroflexi, and Planctomycetes and fungal phyla Ascomycota and Basidiomycota. These results suggested that soil EF appeared more important than CY and SS in shaping the compositions of bacterial and fungal communities. In addition, since fertilizer K has been in the long-term abused in RBB-Region, future vegetable production should pay more attention to K input to reduce the negative effect on soil microbial communities.


Asunto(s)
Producción de Cultivos/métodos , Metales Pesados/análisis , Microbiología del Suelo/normas , Contaminantes del Suelo/análisis , Suelo/química , Acidobacteria/aislamiento & purificación , Ascomicetos/aislamiento & purificación , Basidiomycota/aislamiento & purificación , Biodiversidad , China , Producción de Cultivos/normas , Ecosistema , ARN Ribosómico 16S , Verduras/crecimiento & desarrollo
11.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-750337

RESUMEN

@#Objective    To compare video-assisted thoracic surgical technique (VATS) and conventional surgical technique (CSM) in mitral valve replacement (MVR). Methods    We retrospectively analyzed clinical data of 93 patients in our hospital with mitral valve replacement between January 2010 and January 2015. The patients were divided into two groups including a VATS group and a CSM group.There were 43 patients with 25 males and 18 females at age of 57.43±5.65 years in the VATS group, and 50 patients with 27 males and 23 females at age of 56.40±6.32 years in the CSM group.The clinical outcomes of the two groups were compared. Results    There was no mortality. Echocardiography was normal in both groups during 1-year follow-up. There was no significant difference between the two groups in the operative time, aortic clamping time, cardiopulmonary bypass (CPB) time, or ventilation time. As compared with the CSM group, the patients in the VATS group had a significantly lower complication rate, shorter chest incision length (5.23±1.36 cm vs. 18.21±3.89 cm), less blood transfusion (1.75±0.25 U vs. 3.15±1.50 U), less chest drainage (202.34±12.12 ml vs. 412.32±21.56 ml) and lower pain score (1.26±0.86 vs. 3.01±1.13), shorter time of postoperative hospital stay (8.20±2.36 d vs. 12.10±3.26 d). Conclusion    MVR under VATS is not only technically feasible, but also with excellent clinical results.

12.
Environ Sci Pollut Res Int ; 23(13): 13076-87, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26996919

RESUMEN

Solar greenhouse is a common facility type used for horticultural crop production in China. However, most solar greenhouse fields have been degraded due to continuous cropping and excessive fertilizer use. Therefore, we investigated solar greenhouse soils covering a wide range of cultivation years and environmental conditions in Round-Bohai Bay-Region to test the effects of cultivation year and biogeography on nutrients, heavy metals, and phthalate acid esters (PAEs). In general, soil pH decreased while soil electrical conductivity (EC), organic matter (OM), total nitrogen (TN), NO3 (-)-N, NH4 (+)-N, mineral nitrogen (MN), Olsen-P, and NH4OAc-K contents increased as time of cultivation increased. However, this trend was influenced by sampling sites. Among sampling sites, Jiangsu showed a relatively low soil pH and high Olsen-P content, while Hebei showed a relatively high soil EC value, NO3 (-)-N, NH4 (+)-N, MN, and NH4OAc-K contents. Liaoning was characterized by relatively high soil OM and TN contents. The nutrient level indexes in evaluation of soil quality on Olsen-P and NH4OAc-K exceeded the standard seriously. The maximum values of the heavy metals Cd, Cu, and Zn were 4.87, 2.78, and 1.15 times higher than the threshold values, respectively. There was a rising trend on the heavy metal contents with the increasing cultivation years, and this trend was significantly influenced by sampling sites. Both Cu and Zn had relative high heavy metal indexes in evaluation of soil pollution. The PAEs were not detected in almost all sampling soils. Overall, the excessive fertilizer application was an important cause of nutrient accumulation and heavy metal pollution, resulting in soil degradation in solar greenhouses.


Asunto(s)
Agricultura , Metales Pesados/análisis , Ácidos Ftálicos/análisis , Contaminantes del Suelo/análisis , Suelo/química , Bahías , China , Monitoreo del Ambiente
13.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 31(5): 530-2, 2013 Oct.
Artículo en Chino | MEDLINE | ID: mdl-24298810

RESUMEN

OBJECTIVE: Using tooth whitening agents (bleaching clip) in vitro and acidic drinks, we conducted a comparative study of the changes in enamel surface morphology, Ca/P content, and hardness. METHODS: Tooth whitening glue pieces, cola, and orange juice were used to soak teeth in artificial saliva in vitro. Physiological saline was used as a control treatment. The morphology of the four groups was observed under a scanning electron microscope (SEM) immediately after the teeth were soaked for 7 and 14 d. The changes in Ca/P content and microhardness were analyzed. RESULTS: The enamel surfaces of the teeth in the three test groups were demineralized. The Ca/P ratio and the average microhardness were significantly lower than those of the control group immediately after the teeth were soaked (P < 0.05). The Ca/P ratio and microhardness gradually increased after 7 d. No significant difference was observed between the control group and the test groups after 14 d (P > 0.05). CONCLUSION: Bleaching agents caused transient demineralization of human enamel, but these agents could induce re-mineralization and repair of enamel over time. Demineralization caused by bleaching covered a relatively normal range compared with acidic drinks and daily drinking.


Asunto(s)
Esmalte Dental , Peróxido de Hidrógeno , Blanqueadores Dentales , Dureza , Humanos , Saliva Artificial , Propiedades de Superficie , Blanqueamiento de Dientes
14.
Pediatr Cardiol ; 33(2): 316-21, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22037885

RESUMEN

The current study was designed to compare long-term clinical outcomes and costs between video-assisted thoracoscopic surgery (VATS) and transcatheter Amplatzer occlusion (TAO). This study enrolled 294 patients with isolated patent ductus arteriosus (PDA) from April 2002 to April 2007, and 290 of these patients were followed up until April 2010. Of the 294 patients, 196 underwent VATS and 98 accepted TAO for PDA closure. The two groups were similar in terms of demographics and preoperative clinical characteristics. No cardiac deaths occurred in either group. All the patients in the VATS group had successful PDA closure, and 94 patients (94/98, 95.9%) in the TAO group had successful PDA occlusion. The incidence of acute procedure-related complications recorded was 1.5% in the VATS group compared with 10.2% in TAO group (P < 0.05). The cost per patient was $1,309.40 ± $312.20 in the VATS group and $3,415.80 ± $637.30 in the TAO group (P < 0.05). There were no cardiac deaths or newly occurring arrhythmias in either group during the fellow-up period. Up to the latest follow-up, no late recanalization or residual shunting was documented, and heart structure returned to normal level in the VATS group. However, residual shunting was detected in four more TAO patients. This study confirmed the long-term safety and efficacy of VATS clipping of PDA. Compared with TAO, PDA interrupted with VATS can achieve both excellent clinical results and satisfying cost effectiveness. The cost for VATS is only a little more than one third the cost for TAO.


Asunto(s)
Cateterismo Cardíaco/economía , Conducto Arterioso Permeable/economía , Conducto Arterioso Permeable/cirugía , Dispositivo Oclusor Septal/economía , Cirugía Torácica Asistida por Video/economía , Adolescente , Adulto , Niño , Preescolar , Análisis Costo-Beneficio , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Resultado del Tratamiento , Adulto Joven
15.
Pediatr Cardiol ; 32(4): 386-90, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21188372

RESUMEN

This study was designed to compare the long-term clinical outcomes and costs between video-assisted thoracic surgery (VATS) and posterolateral thoracotomy (PT) in neonates and infants. This study enrolled 302 patients with isolated patent ductus arteriosus (PDA) from January 2002 to 2007 and followed them up until April 2010. A total of 134 patients underwent total VATS (VATS group), and 168 underwent PDA closure through PT (PT group). The two groups were compared according to clinical outcomes and costs. The demographics and preoperative clinical characteristics of the patients were similar in the two groups. No cardiac deaths occurred, and the closure rate was 100% successful in both groups. The operating, recovery, and pleural fluid drainage times were significantly shorter in the VATS group than in the PT group. Statistically significant differences in length of incision, postoperative temperature, and acute procedure-related complications were observed between the two groups. The cost was $1,150.3 ± $221.2 for the VATS group and $2415.8 ± $345.2 for the PT group (P < 0.05). No cardiac deaths or newly occurring arrhythmias were detected in either group during the follow-up period. Statistically significant differences in the rate of residual shunt and scoliosis were observed between the two groups. The left ventricular end-diastolic diameter and the pulmonary artery diameter could be restored to normal in the VATS group but not in the PT group. The study confirmed that VATS offers a minimally traumatic, safe, and effective technique for PDA interruption in neonates and infants.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Conducto Arterioso Permeable/cirugía , Técnicas de Sutura/instrumentación , Cirugía Torácica Asistida por Video/métodos , Toracotomía/métodos , Procedimientos Quirúrgicos Cardíacos/economía , Preescolar , Análisis Costo-Beneficio , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Cirugía Torácica Asistida por Video/economía , Toracotomía/economía , Resultado del Tratamiento
16.
J Hazard Mater ; 177(1-3): 738-42, 2010 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-20074852

RESUMEN

The thermal decomposition of 3,4-bis(4'-aminofurazano-3') furoxan (BAFF) was studied by DSC, TG, the combination technique of in situ thermolysis cell with rapid-scan Fourier transform infrared spectroscopy (thermolysis/RSFT-IR) and the fast thermolysis probe with rapid-scan Fourier transform infrared spectroscopy (fast thermolysis/RSFT-IR). The result shows that the melting point of BAFF is 168.4 degrees C, the peak temperatures of the two exothermic peaks are respectively 260.4 degrees C and 338.8 degrees C on DSC curve. The apparent activation energy E(a) and the pre-exponential factor A are respectively 122.21 kJ mol(-1) and 10(9.89)s(-1) for major exothermic decomposition process of BAFF. The kinetic equation of major exothermic decomposition for BAFF is dalpha/dt=10(10.07)exp(-1.46993 x 10(4)/T)(1-alpha) [-ln(1-alpha)](1/3). The thermal decomposition gaseous products of BAFF consist of CO(2), NO(2), N(2)O and NO. The BAFF is shown by IR spectroscopy to convert to ammonium dicyanamide (NH(4)[N(CN)(2)]), cyclic azine residues (melamine or melamine-like).


Asunto(s)
Calor , Oxadiazoles/química , Rastreo Diferencial de Calorimetría , Gases , Termodinámica , Triazinas
17.
J Hazard Mater ; 176(1-3): 257-61, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19959284

RESUMEN

A bismuth 3-nitro-1,2,4-triazol-5-one (Bi-NTO) complex was prepared and characterized, and its effects on the thermal behaviors, non-isothermal decomposition reaction kinetics, and burning rates of the double-base (DB) propellant containing the mixed ester of triethyleneglycol dinitrate (TEGDN) and nitroglycerin (NG) with Bi-NTO complex as a ballistic modifier were investigated by thermogravimetry and derivative thermogravimetry (TG-DTG), and differential scanning calorimetry (DSC). The results show that Bi-NTO complex can increase the decomposition heat by 140 J g(-1), and it can change the decomposition reaction mechanism function, the kinetic parameters and kinetic equation of the propellant under 0.1 MPa. Combustion experiment shows that Bi-NTO complex can increase the burning rate and reduce the pressure exponent of the NG/TEGDN/NC propellant effectively, with the increase of the catalysis efficiency by 40%.


Asunto(s)
Incineración , Nitrocompuestos/química , Termodinámica , Triazoles/química , Bismuto , Rastreo Diferencial de Calorimetría , Cinética , Nitratos/química , Nitroglicerina/química , Temperatura , Termogravimetría
18.
Di Yi Jun Yi Da Xue Xue Bao ; 23(8): 856-8, 2003 Aug.
Artículo en Chino | MEDLINE | ID: mdl-12919920

RESUMEN

OBJECTIVE: To investigate the understanding of the nurses of different levels concerning Total Quality Control (TQC). METHODS: A total of 198 nurses using stratified random sampling in proportion to the ratio of different levels of the nurses. A questionnaire with approved validity was used in the survey, and the results were statistically analyzed. RESULTS: In terms of basic knowledge of TQC, the scores of assistant nurses the lowest (P<0.05), and the responsible nurses had lower scores than head nurses and nursing officers (P<0.05), while the scores of the nurses whose length of service ranged from 3 to 10 years were lower than those of nurses who had been in service for above 10 years. In terms of TQC common methods, both assistant nurses and responsibility nurses had lower scores than nurses-in-charge, head nurses and nursing officers (P<0.05). The scores of nurses in service for less than 15 years did not significantly differ, but were obviously lower than those of nurses in service for over 15 years. There was no significant difference between the scores of nurses with different academic degrees. CONCLUSION: The TQC knowledge of the nurses are different based on their working levels and length of service.


Asunto(s)
Conocimiento , Enfermeras y Enfermeros , Adulto , Femenino , Humanos , Persona de Mediana Edad , Control de Calidad
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