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1.
Zhonghua Nei Ke Za Zhi ; 61(4): 377-383, 2022 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-35340183

RESUMO

Objective: To explore the differences of risk stratification of very high-risk or extreme high-risk atherosclerotic cardiovascular diseases (ASCVD) and the attainment rates of low-density lipoprotein cholesterol (LDL-C) management targets evaluated by three different criteria, and the causal attributions of these differences. Methods: Patients with ASCVD were consecutively enrolled from January 1 to December 31 in 2019, and were evaluated for very high-risk or extreme high-risk and LDL-C goal attainment rates with 2018 American guideline on the management of blood cholesterol (2018AG), 2019 China Cholesterol Education Program (CCEP) Expert Advice for the management of dyslipidemias (2019EA) and 2020 Chinese expert consensus on lipid management of very high-risk ASCVD patients(2020EC), respectively. The causal attributions of the differences in attainment rates were analyzed as well. Results: A total of 1 864 ASCVD patients were included in this study. According to 2018AG, 2019EA and 2020EC, the proportions of the patients with very high-risk or extreme high-risk were 59.4%, 90.7%, and 65.6%, respectively. The absolute LDL-C target attainment rates were 37.2%, 15.7%, and 13.7%, respectively, the differences between each two rates were statistically significant (all P<0.001). As to the differences in attainment rates between 2020EC and 2018AG, 61.5% were due to the different LDL-C goal attainment values and 38.5% were caused by the different risk stratifications, while for the differences between 2020EC and 2019EA attainment rates, different LDL-C goal attainment values were responsible for 13.2%, and different risk stratifications were responsible for 86.8% of the differences. Conclusions: There are significant differences in the proportions and LDL-C attainment rates among the three different criteria for very high-risk or extreme high-risk ASCVD. 2020EC showed a moderate proportion of patients with extreme high-risk, and had the lowest LDL-C attainment rate. The differences between 2020EC and 2018AG are mainly due to the LDL-C target values, and the differences between 2020EC and 2019EA are mainly caused by the risk stratifications.


Assuntos
Doenças Cardiovasculares , Colesterol , LDL-Colesterol , Objetivos , Humanos , Medição de Risco
2.
Zhonghua Yi Xue Za Zhi ; 98(17): 1302-1305, 2018 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-29764028

RESUMO

Objective: To explore the clinical and teaching application value of virtual reality technology in preoperative planning and intraoperative guide of glioma located in central sulcus region. Method: Ten patients with glioma in the central sulcus region were proposed to surgical treatment. The neuro-imaging data, including CT, CTA, DSA, MRI, fMRI were input to 3dgo sczhry workstation for image fusion and 3D reconstruction. Spatial relationships between the lesions and the surrounding structures on the virtual reality image were obtained. These images were applied to the operative approach design, operation process simulation, intraoperative auxiliary decision and the training of specialist physician. Results: Intraoperative founding of 10 patients were highly consistent with preoperative simulation with virtual reality technology. Preoperative 3D reconstruction virtual reality images improved the feasibility of operation planning and operation accuracy. This technology had not only shown the advantages for neurological function protection and lesion resection during surgery, but also improved the training efficiency and effectiveness of dedicated physician by turning the abstract comprehension to virtual reality. Conclusion: Image fusion and 3D reconstruction based virtual reality technology in glioma resection is helpful for formulating the operation plan, improving the operation safety, increasing the total resection rate, and facilitating the teaching and training of the specialist physician.


Assuntos
Glioma , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Imagem Multimodal , Interface Usuário-Computador , Realidade Virtual
3.
J Environ Manage ; 147: 194-202, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25291677

RESUMO

Polymerized inorganic coagulants are increasingly being used in the water supply and wastewater treatment process, yet there is limited research on the development of polytitanium coagulants. The aim of this study is to synthesize polytitanium chloride (PTC) coagulants and investigate their coagulation behavior and floc characteristics for humic acid removal in comparison to polyaluminum chloride (PAC). The PTC samples with different B (molar ratios of OH/Ti) values were prepared using an instantaneous base-feeding method, employing sodium carbonate as the basification agent. The coagulation efficiency was significantly influenced by different B values. The results suggest that the humic acid removal increased with the increasing B value for PAC, while the inverse trend was observed for PTC. The optimum B value was chosen at 1.0 and 2.0 for PTC and PAC, respectively. Under the optimum coagulant dose and initial solution pH conditions, the PTC coagulant performed better than the PAC coagulant and the floc properties were significantly improved in terms of floc growth rate and floc size. However, the PAC coagulants produced flocs with better floc recoverability than the PTC coagulants.


Assuntos
Hidróxido de Alumínio/química , Precipitação Química , Cloretos/química , Polímeros/química , Titânio/química , Poluentes Químicos da Água/química , Álcalis , Floculação , Substâncias Húmicas , Soluções , Purificação da Água/métodos
4.
J Environ Manage ; 134: 20-9, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24463732

RESUMO

This study is the first attempt to investigate the effect of total hardness and ionic strength on coagulation performance and the floc characteristics of titanium tetrachloride (TiCl4). Membrane fouling under different total hardness and ionic strength conditions was also evaluated during a coagulation-ultrafiltration (C-UF) hybrid process. Coagulation experiments were performed with two simulated waters, using humic acid (HA, high molecular weight) and fulvic acid (FA, relatively low molecular weight), respectively, as model natural organic matter (NOM). Results show that both particle and organic matter removal can be enhanced by increasing total hardness and ionic strength. Floc characteristics were significantly influenced by total hardness and ionic strength and were improved in terms of floc size, growth rate, strength, recoverability and compactness. The results of the UF tests show that the pre-coagulation with TiCl4 significantly improves the membrane permeate fluxes. Under different total hardness and ionic strength conditions, the membrane permeate flux varied according to both NOM and floc characteristics. The increase in total hardness and ionic strength improved the membrane permeate flux in the case of HA simulated water treatment.


Assuntos
Benzopiranos/química , Substâncias Húmicas , Titânio/química , Poluentes da Água/química , Purificação da Água/métodos , Floculação , Dureza , Membranas Artificiais , Concentração Osmolar , Ultrafiltração/métodos
5.
Environ Sci Technol ; 47(22): 12966-75, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24106890

RESUMO

Polymeric metal coagulants are increasingly being used to improve coagulation efficiency, yet the research on the development of titanium and particularly polytitanium salts remains limited. This study is the first attempt in the synthesis, characterization, and application of polytitanium salts as coagulants. Polytitanium tetrachloride (PTC) solutions with different basicity values B (OH/Ti molar ratio) were prepared using a slow alkaline titration method. Jar tests were conducted to assess coagulation performance using both synthetic and real raw water samples, and the floc characteristics were monitored online using a laser diffraction particle size analyzer. Electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) was utilized to identify various Ti species, with the results providing strong evidence of the presence of various hydrolyzed Ti species in the titanium aqueous phase. Compared to titanium tetrachloride (TiCl4), higher or comparable turbidity and organic matter removal efficiency could be achieved by PTC with improved floc characteristics in terms of size, growth rate, and structure. Besides, the water pH after PTC coagulation was significantly improved toward neutral pH. This study indicates that PTC is an effective and promising coagulant for water purification. Besides, the PTC flocculated sludge was able to recycle and produce functional TiO2 photocatalyst.


Assuntos
Titânio/química , Purificação da Água/métodos , Floculação , Fractais , Polímeros/química , Rios/química , Esgotos/química , Soluções , Espectrometria de Massas por Ionização por Electrospray , Água/química , Difração de Raios X
6.
J Hazard Mater ; 152(1): 221-7, 2008 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17689006

RESUMO

Polyamine flocculants were synthesized by the polycondensation of dimethylamine and epichlorohydrin, in which organic amines, e.g. 1,2-diaminoethane, were used as modifying agents. Different products were obtained by varying the reaction parameters, such as the molar ratio of epichlorohydrin to dimethylamine, the amount of 1,2-diaminoethane and reaction temperature. The polyamine flocculants were characterized by transmission electron microscope (TEM). Their flocculation performance was evaluated with simulated dye liquor and actual printing and dyeing wastewater. The behavior of the flocculants was compared with that of inorganic coagulant, polyaluminum chloride (PAC). The experimental results show that polyamine with the highest viscosity and cationicity could be prepared under following conditions: an epichlorohydrin to dimethylamine molar ratio of 1.5, a reaction temperature of 70 degrees C, a 3% content of 1,2-diaminoethane in the total reaction monomers and a reaction time of 7h. Polyamine polymers can, as flocculants for treating simulated and actual dye wastewater, remove color and COD efficiently. The rate of color removal from reactive red liquor, reactive blue liquor and reductive yellow liquor reached as high as 96%, 97% and 96%, respectively. The highest efficiency of color removal and COD removal from polyamine for treating dye wastewater was 90% and 89%, respectively.


Assuntos
Corantes/isolamento & purificação , Floculação , Resíduos Industriais , Poliaminas/síntese química , Poluentes Químicos da Água/isolamento & purificação , Microscopia Eletrônica de Transmissão
7.
Rev Sci Instrum ; 78(11): 113503, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18052470

RESUMO

A new multichannel HCN interferometer has been developed on HL-2A tokamak, which is characterized by two techniques: (1) the wave-guide HCN laser with cavity length of 6 m to increase the optical resource power and (2) high response room temperature waveguide Schottky diode detectors to obtain good beat signal. The space resolution is 7 cm by the use of focusing metal mirrors mounted on the vacuum chamber and a compensated optical system. In the 2006 experiment campaign, this new interferometer has been applied for plasma density profile and density sawtooth measurement.

8.
Environ Technol ; 28(6): 629-37, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17624103

RESUMO

In this study, the decolorization of textile wastewater using composite flocculants was examined. It was composed of Fe(III) flocculants and polydimethyldiallylammonium chloride (PDMDAAC). The color removal efficiency of the composite flocculants was compared with that of individual flocculants, ferric chloride (FeCl3), polyferric chloride (PFC) and PDMDAAC, respectively. The results showed that the composite flocculants were more efficient than individual ones in color removal. The color removal efficiency of the composite flocculants was found to be related to the weight percentage of PDMDAAC (Wp), basicity (B) of PFC and molecular weight (MW) of PDMDAAC. The removal rate is higher at a larger Wp and MW value and lower B value. Chemical oxygen demand (COD) removal from textile wastewater was also investigated in this study. During color removal by the composite flocculants, only up to 20% COD could be removed from the textile wastewater. FeCl3 was then used to further remove the remaining COD from the decolorized wastewater. This two-step treatment of textile wastewater could achieve a 91.6% reduction in COD and an 88.9% reduction in color.


Assuntos
Cor , Floculação , Resíduos Industriais , Indústria Têxtil , Poluentes Químicos da Água/isolamento & purificação , Recuperação e Remediação Ambiental/instrumentação , Recuperação e Remediação Ambiental/métodos
9.
J Hazard Mater ; 284: 190-200, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25463233

RESUMO

Adsorption of natural organic matter, aggregation and disaggregation have been identified as three of the main processes affecting the fate and behaviour of engineered nanoparticles (ENPs) in aquatic environments. However, although several methods have been developed to study the aggregation behaviour of ENPs in natural waters, there are only a few studies focusing on the fate of such aggregates and their potential disaggregation behaviour. In this study, we proposed and demonstrated a simple method for characterising the aggregation behaviour and aggregate structure of ENPs in different natural waters. Both the aggregate size of ENPs and their adsorption capacity for dissolved organic matter (DOM) were strongly related (R(2)>0.97, p<.05) to the combined effect of initial concentration of dissolved organic matter (DOM) and the ionic strength of the natural waters. The structure of the formed aggregates was strongly correlated (R(2)>0.95, p<.05) to the amount of DOM adsorbed by the ENPs during the aggregation process. Under high ionic strength conditions, aggregation is mainly governed by diffusion and the aggregates formed under these conditions showed the lowest stability and fractal dimension, forming linear, chain-like aggregates. In contrast, under low ionic strength conditions, the aggregate structure was more compact, most likely due to strong chemical binding with DOM and bridging mechanisms involving divalent cations formed during reaction-limited aggregation.


Assuntos
Nanopartículas/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Cálcio/química , Compostos Férricos/química , Fractais , Substâncias Húmicas/análise , Íons , Lasers , Luz , Compostos Orgânicos/química , Concentração Osmolar , Tamanho da Partícula , Análise de Regressão , Espalhamento de Radiação , Resistência ao Cisalhamento , Propriedades de Superfície , Água/química
10.
Water Res ; 36(14): 3573-81, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12230203

RESUMO

Aluminum-silicate polymer composite (PASiC), a new kind of inorganic coagulant, was produced by two approaches: (1) hydroxylation of the mixture of AlCl3 and fresh polysilicate (PASiCc); (2) hydroxylated polyaluminum-chloride (PAC) combined with fresh polysilicate (PASiCm). The PASiC products had the following properties: Al2O3 content = 6.40-7.30%, SiO2 content = 0.40-0.82%, Al/Si ratios = 10-20, basicity (OH/Al molar ratio, denoted B) = 1.2-2.0. The coagulation behaviour of PASiC and PAC under conditions typical for coagulation and flocculation in water treatment were investigated by studying the rate of floc size development, the variety of streaming current value, the efficiency of turbidity removal and the effect of pH on the turbidity removal efficiency, and the stability of PASiC. The results detailed in this study suggest that, compared with PAC, PASiC may enhance aggregating efficiency and give better coagulating effects, but weaken charge effectiveness in coagulation process or become unstable when stored for longer time, especially at higher B value and lower Al/Si ratio. The coagulating effect of PASiC is closely linked to the preparation procedure. With the increase of B value and the decrease of Al/Si ratio, the coagulation efficiency of PASiC increases, and at the same B value and Al/Si ratio, PASiCc seems to give a little better coagulation effect than PASiCm but less stability. The Al/Si ratio should not be too low or the B value should not be too high, otherwise, the PASiC products tend to become cloudy or partly gelatinous, which will make them loss some coagulation efficiency.


Assuntos
Silicatos de Alumínio/química , Purificação da Água/métodos , Cinética , Polímeros
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