Direct Growth of Graphene Nanoribbons for Large-Scale Device Fabrication

Graphene being a zero band gap material hinders the use of its intrinsic form for many applications requiring a moderate band gap, such as field effect transistors and optoelectronic devices. Here we demonstrate a scalable method based on chemical vapor deposition for the direct growth of well-registered graphene nanoribbons on SiO₂ substrates with precise control over their width, length, and position. The width of the graphene nanoribbons (∼20 nm) is defined by the thickness of catalyst film, therefore avoiding the diffraction limit of conventional optical lithographic methods. The carrier mobility (over 1000 cm²/V·s) is higher than those previously reported graphene nanoribbons fabricated on SiO₂ substrates, thanks to the present transfer-free and contaminant-free direct growth process. This method overcomes many practical limitations of the previously demonstrated methods for the patterning of graphene nanoribbons and is compatible with large-scale fabrication of graphene nanoelectronics

Chemical Etching, Thermally Driven Combination Strategy to Fabricate Superhydrophobic Fe-Based Amorphous Coatings with Excellent Anticorrosion Property: Based on Hydroxylation Effect

Fe-based amorphous coatings are ideal materials for surface protection due to their outstanding mechanical properties and corrosion resistance. However, coating defects are inevitably formed during the preparation of coatings by thermal spray technology, which seriously affects the corrosion performance. Inspired by bionics, conceiving superhydrophobic surfaces with liquid barrier properties has become a new idea for the corrosion protection of metal surfaces. In this work, based on surface hydroxylation, we designed a superhydrophobic Fe-based amorphous coating with corrosion resistance by chemical etching combined with a thermally driven preparation strategy. The obtained superhydrophobic coatings exhibit liquid repellency (contact angle >150°) and excellent corrosion resistance (corrosion current density and passive current density reduced by 3 orders of magnitude). The results revealed that the superhydrophobic behavior stems from the construction of hydroxyl-induced surface micro-/nanomultilevel aggregates (cluster structures). The hydrophobic agent layer deposited on the surface of cluster aggregates and the nanoparticle elements that constitute the clusters dominate the corrosion resistance of the coating. This work provides an effective guide to the design of high-corrosion-resistant Fe-based amorphous alloy coatings and promotes their engineering applications

Chemical Etching, Thermally Driven Combination Strategy to Fabricate Superhydrophobic Fe-Based Amorphous Coatings with Excellent Anticorrosion Property: Based on Hydroxylation Effect

Fe-based amorphous coatings are ideal materials for surface protection due to their outstanding mechanical properties and corrosion resistance. However, coating defects are inevitably formed during the preparation of coatings by thermal spray technology, which seriously affects the corrosion performance. Inspired by bionics, conceiving superhydrophobic surfaces with liquid barrier properties has become a new idea for the corrosion protection of metal surfaces. In this work, based on surface hydroxylation, we designed a superhydrophobic Fe-based amorphous coating with corrosion resistance by chemical etching combined with a thermally driven preparation strategy. The obtained superhydrophobic coatings exhibit liquid repellency (contact angle >150°) and excellent corrosion resistance (corrosion current density and passive current density reduced by 3 orders of magnitude). The results revealed that the superhydrophobic behavior stems from the construction of hydroxyl-induced surface micro-/nanomultilevel aggregates (cluster structures). The hydrophobic agent layer deposited on the surface of cluster aggregates and the nanoparticle elements that constitute the clusters dominate the corrosion resistance of the coating. This work provides an effective guide to the design of high-corrosion-resistant Fe-based amorphous alloy coatings and promotes their engineering applications

Chemical Etching, Thermally Driven Combination Strategy to Fabricate Superhydrophobic Fe-Based Amorphous Coatings with Excellent Anticorrosion Property: Based on Hydroxylation Effect

Fe-based amorphous coatings are ideal materials for surface protection due to their outstanding mechanical properties and corrosion resistance. However, coating defects are inevitably formed during the preparation of coatings by thermal spray technology, which seriously affects the corrosion performance. Inspired by bionics, conceiving superhydrophobic surfaces with liquid barrier properties has become a new idea for the corrosion protection of metal surfaces. In this work, based on surface hydroxylation, we designed a superhydrophobic Fe-based amorphous coating with corrosion resistance by chemical etching combined with a thermally driven preparation strategy. The obtained superhydrophobic coatings exhibit liquid repellency (contact angle >150°) and excellent corrosion resistance (corrosion current density and passive current density reduced by 3 orders of magnitude). The results revealed that the superhydrophobic behavior stems from the construction of hydroxyl-induced surface micro-/nanomultilevel aggregates (cluster structures). The hydrophobic agent layer deposited on the surface of cluster aggregates and the nanoparticle elements that constitute the clusters dominate the corrosion resistance of the coating. This work provides an effective guide to the design of high-corrosion-resistant Fe-based amorphous alloy coatings and promotes their engineering applications

Chemical Etching, Thermally Driven Combination Strategy to Fabricate Superhydrophobic Fe-Based Amorphous Coatings with Excellent Anticorrosion Property: Based on Hydroxylation Effect

Fe-based amorphous coatings are ideal materials for surface protection due to their outstanding mechanical properties and corrosion resistance. However, coating defects are inevitably formed during the preparation of coatings by thermal spray technology, which seriously affects the corrosion performance. Inspired by bionics, conceiving superhydrophobic surfaces with liquid barrier properties has become a new idea for the corrosion protection of metal surfaces. In this work, based on surface hydroxylation, we designed a superhydrophobic Fe-based amorphous coating with corrosion resistance by chemical etching combined with a thermally driven preparation strategy. The obtained superhydrophobic coatings exhibit liquid repellency (contact angle >150°) and excellent corrosion resistance (corrosion current density and passive current density reduced by 3 orders of magnitude). The results revealed that the superhydrophobic behavior stems from the construction of hydroxyl-induced surface micro-/nanomultilevel aggregates (cluster structures). The hydrophobic agent layer deposited on the surface of cluster aggregates and the nanoparticle elements that constitute the clusters dominate the corrosion resistance of the coating. This work provides an effective guide to the design of high-corrosion-resistant Fe-based amorphous alloy coatings and promotes their engineering applications

Additional file 2 of The impact of COVID-19 on primary health care and antibiotic prescribing in rural China: qualitative study

Additional file

Additional file 3 of The impact of COVID-19 on primary health care and antibiotic prescribing in rural China: qualitative study

Additional file

Additional file 1 of The impact of COVID-19 on primary health care and antibiotic prescribing in rural China: qualitative study

Additional file

Data_Sheet_2_Relationships Between Diagnosis, Bacterial Isolation, and Antibiotic Prescription in Out Patients With Respiratory Tract Infection Symptoms in Rural Anhui, China.PDF

ObjectivesThis paper aims to explore the direct associations of antibiotics prescription with clinical diagnosis and bacterial detection. It also analyses the relations of clinical diagnosis with symptoms and bacterial detection, with a hope of revealing indirect links to antibiotic prescription.MethodsThe study was implemented in one village clinic and one township health center in each of four rural residential areas in Anhui Province, China. Observations were conducted to record clinical diagnosis and antibiotic prescription. A semi-structured questionnaire survey was used to collected patients' sociodemographic information and reported symptoms. Sputum and throat swabs were collected for bacterial culture.ResultsAmong 1,068 patients presenting in the study settings who received a diagnosis of respiratory tract infection (RTI), 87.8% of prescriptions included an antibiotic and 35.8% included two or more antibiotics. Symptomatic RTI patients to the site clinics were diagnosed mainly as having upper respiratory tract infection (32.0%), bronchitis/tracheitis (23.4%), others (16.6%), pharyngitis (11.1%), common cold (8.0%), pneumonia/bronchopneumonia (4.6%) and tonsillitis (4.3%). These clinical diagnosis were associated with symptoms to a varied degree especially for upper respiratory tract infection and bronchitis/tracheitis. Prescription of any antibiotics was positively associated with diagnosis of bronchitis/tracheitis (OR: 5.00, 95% CI: 2.63–9.51), tonsillitis (OR: 4.63, 95% CI: 1.48–14.46), pneumonia/bronchopneumonia (OR: 4.28, 95% CI: 1.40–13.04), pharyngitis (OR: 3.22, 95% CI: 1.57–6.59) and upper respiratory tract infection (OR: 3.04, 95% CI: 1.75–5.27). Prescription of two or more antibiotics was statistically significant related to diagnosis of bronchitis/ tracheitis (OR: 2.20, 95% CI: 1.44–3.35) or tonsillitis (OR: 2.97, 95% CI: 1.47–6.00). About 30% of the patients were identified with some type of bacteria. Bacteria detection was linked with pharyngitis (OR: 0.50, 95% CI: 0.28–0.88) but not prescription of antibiotics.ConclusionsAntibiotics prescription were found with a strong relation to diagnosis of RTIs given by the clinician but was not associated with the presence of bacteria in patient samples. Part of the diagnosis may have been given by the clinician to justify their antibiotics prescription. There is clear need to use additional measures (e.g., symptoms) in conjunction with diagnosis to supervise or audit excessive antibiotics use.</p

Data_Sheet_1_Relationships Between Diagnosis, Bacterial Isolation, and Antibiotic Prescription in Out Patients With Respiratory Tract Infection Symptoms in Rural Anhui, China.PDF

ObjectivesThis paper aims to explore the direct associations of antibiotics prescription with clinical diagnosis and bacterial detection. It also analyses the relations of clinical diagnosis with symptoms and bacterial detection, with a hope of revealing indirect links to antibiotic prescription.MethodsThe study was implemented in one village clinic and one township health center in each of four rural residential areas in Anhui Province, China. Observations were conducted to record clinical diagnosis and antibiotic prescription. A semi-structured questionnaire survey was used to collected patients' sociodemographic information and reported symptoms. Sputum and throat swabs were collected for bacterial culture.ResultsAmong 1,068 patients presenting in the study settings who received a diagnosis of respiratory tract infection (RTI), 87.8% of prescriptions included an antibiotic and 35.8% included two or more antibiotics. Symptomatic RTI patients to the site clinics were diagnosed mainly as having upper respiratory tract infection (32.0%), bronchitis/tracheitis (23.4%), others (16.6%), pharyngitis (11.1%), common cold (8.0%), pneumonia/bronchopneumonia (4.6%) and tonsillitis (4.3%). These clinical diagnosis were associated with symptoms to a varied degree especially for upper respiratory tract infection and bronchitis/tracheitis. Prescription of any antibiotics was positively associated with diagnosis of bronchitis/tracheitis (OR: 5.00, 95% CI: 2.63–9.51), tonsillitis (OR: 4.63, 95% CI: 1.48–14.46), pneumonia/bronchopneumonia (OR: 4.28, 95% CI: 1.40–13.04), pharyngitis (OR: 3.22, 95% CI: 1.57–6.59) and upper respiratory tract infection (OR: 3.04, 95% CI: 1.75–5.27). Prescription of two or more antibiotics was statistically significant related to diagnosis of bronchitis/ tracheitis (OR: 2.20, 95% CI: 1.44–3.35) or tonsillitis (OR: 2.97, 95% CI: 1.47–6.00). About 30% of the patients were identified with some type of bacteria. Bacteria detection was linked with pharyngitis (OR: 0.50, 95% CI: 0.28–0.88) but not prescription of antibiotics.ConclusionsAntibiotics prescription were found with a strong relation to diagnosis of RTIs given by the clinician but was not associated with the presence of bacteria in patient samples. Part of the diagnosis may have been given by the clinician to justify their antibiotics prescription. There is clear need to use additional measures (e.g., symptoms) in conjunction with diagnosis to supervise or audit excessive antibiotics use.</p