Molecular Insights into the Stability of Titanium in Electrolytes Containing Chlorine and Fluorine Ions.

Titanium and its alloys are protected by a compact and stable passive film, which confers resistance to corrosion by the primary halogen chloride (Cl-) while being less effective against fluoride (F-). Although researchers have recognized different macroscopic corrosion effects of these halide ions on titanium, the underlying mechanisms remain largely unexplored. In this work, the bonding of Cl-/F- with stable passive films was studied in neutral and acidic (pH = 2.3) conditions. The synergistic effect between the interfacial hydrogen bond (HB) structure and halogens on titanium corrosion was first revealed using first-principles calculation and Raman spectroscopy. F- forms more stable halogen-Ti bonds than Cl-, resulting in titanium degradation. The proton combined with F- exhibits a specific synergistic effect, causing corrosion of the passive film. The water hydrogen bond transformation index (HBTI) at the titanium/aqueous interface was 1.88 in an acidic solution containing F-, significantly higher than that in neutral/acid solutions containing Cl- (1.80/1.81) and a neutral solution containing F- (1.81). This work clarifies the structure-activity relationship between HBTI and the destruction of titanium passive films. We propose that the microstructure of the interfacial HB is an undeniable factor in the corrosion of titanium.

[Investigation on the current situation of the development of intensive care units in Inner Mongolia Autonomous Region in 2022].

OBJECTIVE: To investigate the development present situation of the department of critical care medicine in Inner Mongolia Autonomous Region (hereinafter referred to as Inner Mongolia), in order to promote the standardized and homogeneous development of critical care medicine in Inner Mongolia, and also provide a reference for discipline construction and resource allocation. METHODS: A survey study was conducted in comprehensive intensive care unit (ICU) of tertiary and secondary hospitals in Inner Mongolia by online questionnaire survey and telephone data verification. The questionnaire was based on the Guidelines for the Construction and Management of Intensive Care Units (Trial) (hereinafter referred to as the Guidelines) issued by the National Health Commission in 2009 and the development trend of the discipline. The questionnaire covered six aspects, including hospital basic information, ICU basic information, personnel allocation, medical quality management, technical skill and equipment configuration. The questionnaire was distributed in September 2022, and it was filled out by the discipline leaders or department heads of each hospital. RESULTS: As of October 24, 2022, a total of 101 questionnaires had been distributed, 85 questionnaires had been recovered, and the questionnaire recovery rate had reached 84.16%, of which 71 valid questionnaires had been collected in a total of 71 comprehensive ICU. (1) There were noticeable regional differences in the distribution of comprehensive ICU in Inner Mongolia, with a relatively weak distribution in the east and west, and the overall distribution was uneven. The development of critical care medicine in Inner Mongolia was still lacking. (2) Basic information of hospitals: the population and economy restricted the development of ICU. The average number of comprehensive ICU beds in the western region was only half of that in the central region (beds: 39.0 vs. 86.0), and the average number of ICU beds in the eastern region was in the middle (83.6 beds), which was relatively uneven. (3) Basic information of ICU: among the 71 comprehensive ICU surveyed, there were 44 tertiary hospitals and 27 secondary hospitals. The ratio of ICU beds to total beds in tertiary hospitals was significantly lower than that in secondary hospitals [(1.59±0.81)% vs. (2.11±1.07)%, P < 0.05], which were significantly lower than the requirements of the Guidelines of 2%-8%. The utilization rate of ICU in tertiary and secondary hospitals [(63.63±22.40)% and (44.65±20.66)%, P < 0.01] were both lower than the bed utilization rate required by the Guidelines (75% should be appropriate). (4) Staffing of ICU: there were 376 doctors and 1 117 nurses in tertiary hospitals, while secondary hospitals had 122 doctors and 331 nurses. There were significant differences in the composition ratio of the titles of doctors, the degree of doctors, and the titles of nurses between tertiary and secondary hospitals (all P < 0.05). Most of the doctors in tertiary hospitals had intermediate titles (attending physicians accounted for 41.49%), while most of the doctors in secondary hospitals had junior titles (resident physicians accounted for 43.44%). The education level of doctors in tertiary hospitals was generally higher than that in secondary hospitals (doctors: 2.13% vs. 0, masters: 37.24% vs. 8.20%). The proportion of nurses in tertiary hospitals was significantly lower than that in secondary hospitals (17.01% vs. 24.47%). The ratio of ICU doctors/ICU beds [(0.64±0.27)%, (0.59±0.34)%] and ICU nurses/ICU beds [(1.76±0.56)%, (1.51±0.48)%] in tertiary and secondary hospitals all failed to meet the requirements above 0.8 : 1 and 3 : 1 of the Guidelines. (5) Medical quality management of ICU: compared with secondary hospitals, the proportion of one-to-one drug-resistant bacteria care in tertiary hospitals (65.91% vs. 40.74%), multimodal analgesia and sedation (90.91% vs. 66.67%), and personal digital assistant (PDA) barcode scanning (43.18% vs. 14.81%) were significantly higher (all P < 0.05). (6) Technical skills of ICU: in terms of technical skills, the proportion of bronchoscopy, blood purification, jejunal nutrition tube placement and bedside ultrasound projects carried out in tertiary hospitals were higher than those in secondary hospitals (84.09% vs. 48.15%, 88.64% vs. 48.15%, 61.36% vs. 55.56%, 88.64% vs. 70.37%, all P < 0.05). Among them, the placement of jejunal nutrition tube, bedside ultrasound and extracorporeal membrane oxygenation were mainly completed independently in tertiary hospitals, while those in secondary hospitals tended to be completed in cooperation. (7) Equipment configuration of ICU: in terms of basic equipment, the ratio of the total number of ventilators/ICU beds in tertiary and secondary hospitals [0.77% (0.53%, 1.07%), 0.88% (0.63%, 1.38%)], and the ratio of injection pump/ICU beds [1.70% (1.00%, 2.56%), 1.25% (0.75%, 1.88%)] didn't meet the requirements of the Guidelines. The equipment ratio was insuffcient, which means that the basic needs of development had not been met yet. CONCLUSIONS: The development of comprehensive ICU in Inner Mongolia has tended to mature, but there is still a certain gap in the development scale, personnel ratio and instruments and equipment compared with the Guidelines. Moreover, the comprehensive ICU appears the characteristics of relatively weak eastern and western regions, and the overall distribution is uneven. Therefore, it is necessary to increase efforts to invest in the construction of the department of critical care medicine.

Application of immunomodulatory therapy in a human brucellosis patient with pancytopenia: A case report.

Brucellosis is a common zoonotic infectious disease with diverse and non-specific clinical manifestations caused by Brucella. Although Brucella can cause damage to multiple systems in the human body, hematological complications are relatively rare. We present a case of a 47-year-old male brucellosis patient with pancytopenia. In May 2018, the patient was diagnosed with brucellosis and recovered after receiving antibiotic treatment (rifampicin 600 mg/day and doxycycline 200 mg/day) for six weeks. However, after three years, the patient experienced a recurring high fever. Brucellosis relapse was confirmed based on the patient's clinical history, Rose Bengal plate agglutination test and standard tube agglutination test results. Routine blood examination revealed a decrease in the whole blood cell count, suggesting bone marrow suppression. Bone marrow aspiration and bacterial culture confirmed the diagnosis of brucellosis with pancytopenia. Antibiotic treatment failed to effectively improve the patient's condition. Therefore, a combination of immunomodulatory and antibiotic treatments was used. The antibiotic regimen included oral rifampicin 600 mg/day, intravenous doxycycline hydrochloride 200 mg/day, and subcutaneous injection of human granulocyte-stimulating factor (0.2 mg/day). Immunomodulatory therapy consisted of 20,000 mg/day intravenous human immunoglobulin (pH 4) for five days and 800 mg/day oral pidotimod liquid for 20 days. As the treatment progressed, the count gradually recovered to normal levels, and the symptoms of bone marrow suppression were alleviated. PCR testing revealed the absence of Brucella DNA in both monocyte and serum samples. Furthermore, negative standard tube agglutination test results were obtained. These findings indicate that the immunomodulatory therapy resulted in a complete clearance of Brucella. Therefore, immunomodulatory therapy could be an effective option in cases of brucellosis with pancytopenia that are unresponsive to conventional antibiotic treatment. Further research and clinical evidence are required to confirm and optimize the use of immunomodulatory therapies in patients with brucellosis.

Insight into oxygen reduction activity and pathway on pure titanium using scanning electrochemical microscopy and theoretical calculations.

HYPOTHESIS: Unlike noble metals, the oxygen reduction reaction (ORR) behavior on Ti is more complicated due to its spontaneously formed oxide film. This film results in sluggish ORR kinetics and tends to be reduced within ORR potential region, causing the weak and multi-reaction coupled current. Though Ti is being used in chemical and biological fields, its ORR research is still underexplored. EXPERIMENTS: We innovatively employed the modified reactive tip generation-substrate collection (RTG/SC) mode of scanning electrochemical microscopy (SECM) with high efficiency of 97.2 % to quantitatively study the effects of film characteristics, solution environment (pH, anion, dissolved oxygen), and applied potential on the ORR activity and selectivity of Ti. Then, density functional theory (DFT) and molecular dynamics (MD) analyses were employed to elucidate its ORR behavior. FINDINGS: On highly reduced Ti, film properties dominate ORR behavior with promoted 4e- selectivity. Rapid film regeneration in alkaline/O2-saturated conditions inhibits ORR activity. Besides, ORR is sensitive to anion species in neutral solutions while showing enhanced 4e- reduction in alkaline media. All the improved 4e- selectivities originate from the hydrogen bond/electrostatic stabilization effect, while the decayed ORR activity by Cl- arises from the suppressed O2 adsorption. This work provides theoretical support and possible guidance for ORR research on oxide-covered metals.

Spectroscopic and Simulation Insights into the Corrosion Mechanism of Sulfite on Titanium.

Ion adsorption and hydrogen bond (HB) network reconstruction in electric double layer (EDL) have a profound impact on the interface properties. The microstructure in the bulk phase of 1.00-21.30 wt.% Na2SO3 aqueous solutions are investigated by X-ray scattering, confocal Raman spectroscopy, and classical molecular dynamics. The electronic properties of SO32- adsorption and the geometric structure of the HB network in the EDL at the titanium TiO2(101) surface are studied by density functional theory (DFT) and classical molecular dynamics. The SO32- strongly weakens the fully hydrogen-bonded water (FHW) and transforms it into partial hydrogen-bonded water (PHW). The HB transformation index (HBTI = PHW/FHW) shows a linear relationship with the mass fraction of Na2SO3. The TiOb-parallel adsorption configuration of SO32- enhances the ionicity of the Ob-Ti6 bond, resulting in the formation of oxygen vacancies at the titanium passive film surface. Besides, SO32- and Na+ are enriched and thermodynamic supersaturated in the inner Helmholtz layer (IHL), and the ions are diluted in the outer Helmholtz layer (OHL). The diffusion coefficient of SO32- and water molecules in EDL decreases seriously, which is easy to causes salt scaling on the surface of titanium passive film. This work provides evidence for the destruction of titanium passive film by SO32-.

Interfacial Adsorption and Electron Properties of Water Molecule/Cluster on Anatase TiO2(101) Surface: Raman and DFT Investigation.

The hydrogen bond network reconstruction at the titanium/water interface was monitored by Raman spectroscopy. In addition, the adsorption properties and the surface electron properties of hydrogen bond cluster (HBC) configurations were analyzed using adsorption energy, work function, Mulliken charge population, and density of states (DOS) by the first-principles method based on density functional theory (DFT). Our results show that the hydrogen bond network of the aqueous solution is reconstructed under the interaction with the anatase TiO2(101) surface with the transformation of the chain and free hydrogen bonds to complex hydrogen bonds. The adsorption energy of a single water molecule and HBC on the anatase TiO2(101) surface are the lowest with the 1-DD-h (-0.851 eV) and 3-D-h-DDA (-1.048 eV) configurations, respectively. Over the long term, artificially regulating the structure of the HBC might be an effective and general way to slow down the metal anodic reaction without surface modification. Furthermore, the surface charge concentrates on the bridging oxygen atom, which will be the active site of the interface reaction. It is helpful to clarify the anodic corrosion reaction mechanism of the titanium spontaneous oxide film/water interface.

An Fe-V@NiO heterostructure electrocatalyst towards the oxygen evolution reaction.

The development of a nonprecious and Earth-abundant electrocatalyst with high electrocatalytic activity for the oxygen evolution reaction (OER) is an emerging hot issue and remains a grand challenge. In the present work, we proposed a facile strategy to construct ultrathin NiO nanosheets decorated with Fe-V nanoparticles on nickel foam (Fe-V@NiO/NF) for use as an OER electrocatalyst. Due to the 3D rational configuration, the Fe-V@NiO/NF with a heterostructure shows excellent electrocatalytic activity towards the OER. Interestingly, it is found that in situ oxidation by galvanostatic electrolysis in alkaline solution is beneficial to enhance the OER performance. After 10 h of electrolysis, a current density of 50 mA cm-2 is achieved at a low overpotential of 271.1 mV. This is because during the in situ oxidation process, iron and vanadium ions insert into the NiO lattice and lead to the generation of highly active α-FeOOH and an amorphous (oxy)-hydroxide layer. Additionally, the charge transfer resistance dramatically reduces with the prolonging of oxidation time.

Highly porous copper ferrite foam: A promising adsorbent for efficient removal of As(III) and As(V) from water.

A novel copper ferrite foam fabricated on Fe-Ni foam substrate was synthesized via a simple hydrothermal method to efficiently remove arsenic from aqueous solution. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-Ray diffraction pattern (XRD) and Raman spectra were used to characterize the morphology and surface composition of the copper ferrite foam (CFF). The adsorption behavior of As(III) and As(V) onto this CFF is studied as a function of solution pH, temperature, contact time, and different concentrations. Results shown that this CFF has high adsorption capacity and excellent recyclability. Adsorption isotherms study indicates Langmuir model of adsorption. The maximum adsorption capability of As(III) and As(V) on CuFe2O4 foam is observed about 44.0 mg g-1 and 85.4 mg g-1, respectively. Regeneration experiment indicates that arsenic could be easily desorbed from CFF with 0.10 mol L-1 NaOH and the high adsorption capacity can be maintained for six regeneration cycle.

An internal magnetic field strategy to reuse pulverized active materials for high performance: a magnetic three-dimensional ordered macroporous TiO2/CoPt/α-Fe2O3 nanocomposite anode.

A ferromagnetic three-dimensional ordered macroporous TiO2/CoPt/α-Fe2O3 (3DOMTCF) nanocomposite was synthesized via a sol-gel approach templated by poly(methyl methacrylate) (PMMA) microspheres. After magnetization, it exhibited an extremely high reversible capacity and a long cycle life, which were ascribed to the internal magnetic field for reusing pulverized active materials and its unique structure.

Copper-promoted cementation of antimony in hydrochloric acid system: A green protocol.

A new method of recovering antimony in hydrochloric acid system by cementation with copper powder was proposed and carried out at laboratory scale. Thermodynamic analysis and cyclic voltammetry test were conducted to study the cementation process. This is a novel antimony removal technology and quite meets the requirements of green chemistry. The main cement product Cu2Sb is a promising anodic material for lithium and sodium ion battery. And nearly all consumed copper powder are transformed into CuCl which is an important industrial material. The effect of reaction temperature, stoichiometric ratio of Cu to Sb(III), stirring rate and concentration of HCl on the cementation efficiency of antimony were investigated in detail. Optimized cementation condition is obtained at 60 °C for 120 min and stirring rate of 600 rpm with Cu/Sb(III) stoichiometric ratio of 6 in 3 mol L(-1) HCl. At this time, nearly all antimony can be removed by copper powder and the cementation efficiency is over 99%. The structure and morphologies of the cement products were characterized by X-ray diffraction and scanning electron microscopy, respectively. Results show that the reaction temperature has little influence on the morphology of the cement products which consist of particles with various sizes. The activation energy of the cementation antimony on copper is 37.75 kJ mol(-1), indicating a chemically controlled step. Inductively coupled plasma mass spectrometry results show that no stibine generates during the cementation process.