Fast Degradation of Rhodamine B by In Situ H2O2 Fenton System with Co and N Co-Doped Carbon Nanotubes.

In this study, an E-fenton oxidation system based on Co-N co-doped carbon nanotubes (Co-N-CNTs) was designed. The Co-N-CNTs system showed fast degradation efficiency and reusability for the degradation of rhodamine B (RhB). The XRD and SEM results showed that the Co-N co-doped carbon nanotubes with diameters ranging from 40 to 400 nm were successfully prepared. The E-Fenton degradation performance of Co-N-CNTs was investigated via CV, LSV and AC impedance spectroscopy. The yield of H2O2 could reach 80 mg/L/h within 60 min, and the optimal voltage and preparation temperature for H2O2 yield in this system was -0.7 V (vs. SCE) and 800 °C. For the target pollutant of RhB, the fast removal of RhB was obtained via the Co-N-CNTS/E-Fenton system (about 91% RhB degradation occurred during 60 min), and the •OH played a major role in the RhB degradation. When the Fe2+ concentrations increased from 0.3 to 0.4 mM, the RhB degradation efficiency decreased from 91% to about 87%. The valence state of Co in the Co-N-C catalyst drove a Co2+/Co3+ cycle, which ensured the catalyst had good E-Fenton degradation efficiency. This work provides new insight into the mechanism of an E-Fenton system with carbon-based catalysts for the efficient degradation of RhB.

[The predictive value of medical big data for the prognosis of elderly patients with pneumonia: based on the result of clinical database of a Beijing Chaoyang Hospital Consortium Chaoyang Emergency Ward].

OBJECTIVE: To explore a medical big data algorithm to screen the core indicators in clinical database that can be used to evaluate the prognosis of elderly patients with pneumonia. METHODS: Based on the clinical database of a Beijing Chaoyang Hospital Consortium Chaoyang Emergency Ward in Beijing Chaoyang Hospital, Capital Medical University, patients with pulmonary infection were selected through the big data retrieval technology. According to the prognosis at the time of discharge, they were divided into death group and survival group. The general data of patients were collected, including gender, age, blood gas and laboratory indices. A computer language called Python was used to make batch calculations of key indicators that affect mortality in elderly patients with pneumonia. Logistic regression analysis was used to analyze the relationship between laboratory indicators and patients' prognosis. Receiver operating characteristic curve (ROC curve) was drawn to analyze the predictive value of screening method for patients' prognosis. RESULTS: A total of 265 patients were included in the study, 64 died and 201 survived. The data of the first detection indexes of each patient after admission were collected, and 23 key indicators with significant differences were selected from 472 indicators: blood routine indicators (n = 7), blood gas indicators (n = 3), tumor markers indicators (n = 3), coagulation related indicators (n = 4), and nutrition and organ function indicators (n = 6). (1) The key indicators of blood gas in patients died of pneumonia: Cl- was 97-111 mmol/L in 51.6% (33 cases) of patients, lactic acid (Lac) was 0.5-2.5 mmol/L in 81.2% (52 cases) of patients, and H+ was 0-46 mmol/L in 87.5% (56 cases) of patients. (2) The key indicators of blood routine of patients died of pneumonia: hemoglobin count (Hb) of 46.9% (30 cases) patients was 80-109 g/L, the eosinophils proportions (EOS%) in 67.2% (43 cases) patients was 0.000-0.009, the lymphocytes proportions (LYM%) in 51.6% (33 cases) patients was 0.00-0.09, the red blood cell count (RBC) in 50.0% (32 cases) patients was (3.0-3.9)×1012/L, the white blood cell count (WBC) in 54.7% (35 cases) patients was (0.0-9.9)×109/L, and the red blood cell volume distribution width coefficientof variability (RDW-CV) in 48.4% (31 cases) patients was 10.0%-14.9%, serum C-reactive protein (CRP) was 0.0-49.9 mg/L in 48.4% (31 cases) patients. (3) The key indicators of tumor markers in patients died of pneumonia: 76.6% (49 cases) of patients had negative free prostate specific antigen/total prostate specific antigen (FPSA/TPSA, the ratio was 0), 92.2% (59 cases) had cytokeratin 19 fragment (CYFRA21-1) between 0.0-11.0 µg/L, and 75.0% (48 cases) had carbohydrate antigen 125 (CA125) between 0-104 kU/L. (4) The key coagulation indexes of patients died of pneumonia: 68.8% (44 cases) of patients had activated partial thromboplastin time (APTT) of 57-96 s, 73.4% (47 cases) of patients had D-dimer of 0-6 mg/L, 93.8% (60 cases) of patients had thrombin time (TT) of 14-22 s, and 89.1% (57 cases) of patients had adenosine diphosphate (ADP) inhibition rate of 0%-53%. (5) Nutrition and organ function key indicatorsin patients died of pneumonia: 92.2% (59 cases) of brain natriuretic peptide (BNP) in patients with 0, 46.9% (30 cases) of patients had prealbumin (PA) of 71-140 mg/L, 90.6% (58 cases) of the patients with uric acid (UA) for 21-41 µmol/L, 75.0% (48 cases) of the patients with albumin (Alb) to 10-20 g/L, 93.5% (60 cases) of patients had albumin/globulin ratio (A/G ratio) of 0-0.9, 84.4% (54 cases) of the patients with lactate dehydrogenase (LDH) from 0-6.68 µmol/L×s-1×L-1. (6) Logistic regression analysis and ROC curve analysis: Logistic regression analysis showed that PA and Lac were the prognostic factors. PA could reduce the risk of death by 0.9%, Lac could increase the risk of death by 69.4%; the area under ROC curve (AUC) between laboratory indicators and the prediction effect of death prediction model for patients' prognosis was 0.80, which showed that the classification effect was better, and this study model could better predict the prognosis of elderly patients with pneumonia. CONCLUSIONS: By using big data technology, 23 core indicators for evaluating the prognosis of elderly patients with pneumonia can be screened from the clinical database of emergency ward, which provides a new perspective and method for clinical evaluation of the prognosis of elderly patients with pneumonia.

Quantifying and understanding the triboelectric series of inorganic non-metallic materials.

Contact-electrification is a universal effect for all existing materials, but it still lacks a quantitative materials database to systematically understand its scientific mechanisms. Using an established measurement method, this study quantifies the triboelectric charge densities of nearly 30 inorganic nonmetallic materials. From the matrix of their triboelectric charge densities and band structures, it is found that the triboelectric output is strongly related to the work functions of the materials. Our study verifies that contact-electrification is an electronic quantum transition effect under ambient conditions. The basic driving force for contact-electrification is that electrons seek to fill the lowest available states once two materials are forced to reach atomically close distance so that electron transitions are possible through strongly overlapping electron wave functions. We hope that the quantified series could serve as a textbook standard and a fundamental database for scientific research, practical manufacturing, and engineering.

Quantifying the triboelectric series.

Triboelectrification is a well-known phenomenon that commonly occurs in nature and in our lives at any time and any place. Although each and every material exhibits triboelectrification, its quantification has not been standardized. A triboelectric series has been qualitatively ranked with regards to triboelectric polarization. Here, we introduce a universal standard method to quantify the triboelectric series for a wide range of polymers, establishing quantitative triboelectrification as a fundamental materials property. By measuring the tested materials with a liquid metal in an environment under well-defined conditions, the proposed method standardizes the experimental set up for uniformly quantifying the surface triboelectrification of general materials. The normalized triboelectric charge density is derived to reveal the intrinsic character of polymers for gaining or losing electrons. This quantitative triboelectric series may serve as a textbook standard for implementing the application of triboelectrification for energy harvesting and self-powered sensing.

A facile sol-gel synthesis of low-fusing titanium opaque porcelain using borate-silicate system and its bioactivity.

The titanium opaque porcelain was synthesized through sol-gel using borate-silicate system. The porcelain was characterized by DSC-TG, X-ray diffraction, N2 adsorption-desorption isotherms and scanning electron microscope tests. The results of DSC showed that the nitrates could be decomposed completely when the bioglass xerogel precursor was heat-treated at 760 ℃. The XRD results showed that the Na2Ca3Si6O16 was the major phase of the opaque porcelain. The synthesized opaque porcelain powders had an average particle size of about 5-25 µm with nanopores of around 50-70 nm on the surface. The BET average surface area of the porcelain was 12.67 m2/g, while the average pore diameters for adsorption and desorption were 9.73 and 10.16 nm, respectively. The flexure strength significantly increased from 47.4 MPa to 116.2 MPa with the sintering temperature increasing from 575 ℃ to 600 ℃. The XRD, FTIR and EDS results proved that hydroxyapatite had formed on the porcelain surface after incubation in simulated body fluid.

Surface modifications and Nano-composite coatings to improve the bonding strength of titanium-porcelain.

Surface modifications of Ti and nano-composite coatings were employed to simultaneously improve the surface roughness, corrosion resistance and chemical bonding between porclain-Ti. The specimens were studied by field-emission scanning electron microscopy, surface roughness, differential scanning calorimetry, Fourier transform infrared spectroscopy, corrosion resistance and bonding strength tests. The SEM results showed that hybrid structures with micro-stripes, nano-pores and nano-protuberances were prepared by surface modification of Ti, which significantly enhanced the surface roughness and corrosion resistance of Ti. Porous nano-composite coatings were synthesized on Ti anodized with pre-treatment in 40% HF acid. TiO2 nanoparticles were added into the hybrid coating to increase the solid phase content of the sols and avoid the formation of microcracks. With the TiO2 content increasing from 45 wt% to 60 wt%, the quantities of the microcracks on the coating surface gradually decreased. The optimal TiO2 content for the nanocomposite coatings is 60 wt% in this research. Compared to the uncoated group, the bonding strength of the coated groups showed a bonding strength improvement of 23.96%. The cytotoxicity of the 4# coating group was ranked as zero, which corresponds to non-cytotoxicity.

Biological properties of nanostructured Ti incorporated with Ca, P and Ag by electrochemical method.

TiO2 nanotube arrays were synthesized on Ti surface by anodic oxidation. The elements of Ca and P were simultaneously incorporated during nanotubes growth in SBF electrolyte, and then Ag was introduced to nanotube arrays by cathodic deposition, which endowed the good osseointegration and antibacterial property of Ti. The bioactivity of the Ti surface was evaluated by simulated body fluid soaking test. The biocompatibility was investigated by in vitro cell culture test. And the antibacterial effect against Staphylococcus aureus was examined by the bacterial counting method. The results showed that the incorporation of Ca, P and Ag elements had no significant influence on the formation of nanotube arrays on Ti surface during electrochemical treatment. Compared to the polished or nanotubular Ti surface, TiO2 nanotube arrays incorporated with Ca, P and Ag increased the formation of bone-like apatite in simulated body fluid, enhanced cell adhesion and proliferation, and inhibited the bacterial growth. Based on these results, it can be concluded that the nanostructured Ti incorporated with Ca, P and Ag by electrochemical method has promising applications as implant material.

Preparation and characterization of a titanium bonding porcelain.

The titanium bonding porcelain was synthesized through normal melting-derived route using borate-silicate system. The porcelain was characterized by thermal expansion, X-ray diffraction, scanning electron microscope and cytotoxicity tests. The results of X-ray diffraction showed that the main phase of the bonding porcelain was SnO2. The SnO2 microcrystals precipitated from the glass matrix when the SnO2 content was increased. The thermal expansion coefficient of bonding porcelains decreased with the increasing concentration of SiO2. The thermal expansion coefficient of bonding porcelains first decreased slightly with the increasing of B2O3 concentration (from 0 wt% to 10 wt%) and then increased to about 9.4×10(-6)/°C(from 10 wt% to 12 wt%). As an intermediate, B2O3 can act as both network formers and modifiers, depending on the relationship between the concentration of basic oxides and intermediates. The Vickers hardness of bonding porcelains increased with the increase of SnO2 concentration. When SnO2 concentration was 6 wt%, only Si and Sn elements attended the reaction between titanium and porcelain and mainly adhesive fracture was found at Ti-porcelain interface. When SnO2 concentration was 12 wt%, failure of the titanium-porcelain predominantly occurred in the bonding porcelain and mainly cohesive fracture was found at Ti-porcelain interface. The methyl thiazolyl tetrazolium assay results demonstrated that the cytotoxicity of the titanium porcelain was ranked as 0.