ABSTRACT
Enhancing catalytic activity while inhibiting the generation of chlorine byproducts is essential in the catalytic oxidation process of chlorinated volatile organic compounds (CVOCs). In this study, Cr-modified Co/WNb catalysts were synthesized and utilized for the degradation of dichloromethane (DCM). It was found that the moderate introduction of Cr exposed more Cr6+ on the catalyst surface due to the interaction between cobalt and chromium oxides, which promoted the generation of more chemisorbed oxygen on the surface, thus improving the redox properties and enhancing the activity of the catalysts. Additionally, the introduction of Cr increased the B acid sites of the catalysts, promoting the breaking of C-Cl bonds and the removal of dissociated Cl- Meanwhile, the improved redox properties also allowed further oxidation of the dissociated activated intermediate products and inhibited the generation of chlorine byproducts. The catalyst activity was optimal when the Cr to Co molar ratio was 4, which the T90 of DCM was 256 °C and the monochloromethane selectivity was only 1.7 %. Moreover, Co4Cr/WNb showed excellent chlorine and water resistance, making it an ideal candidate for CVOC degradation.
ABSTRACT
Objective: To compare the effectiveness of small incision external articular minimally invasive osteotomy and traditional Chevron osteotomy in the treatment of hallux valgus. Methods: A retrospective analysis was conducted on the clinical data of 58 patients (58 feet) with hallux valgus who were admitted between April 2019 and June 2022 and met the selection criteria. Among them, 28 cases were treated with small incision external articular minimally invasive osteotomy (minimally invasive group), and 30 cases were treated with traditional Chevron osteotomy (traditional group). There was no significant difference in baseline data such as age, gender, disease duration, Mann classification, and preoperative inter metatarsal angle (IMA), hallux valgus angle (HVA), distal metatarsal articular angle (DMAA), forefoot width, tibial sesamoid position (TSP) score, American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score, visual analogue scale (VAS) score, psychological score (SF-12 MCS score) and physiological score (SF-12 PCS score) of short-form 12 health survey scale, and range of motion (ROM) of metatarsophalangeal joint between the two groups ( P>0.05). The incision length, operation time, intraoperative blood loss, intraoperative fluoroscopy frequency, weight-bearing walking time, fracture healing time, and incidence of complications were recorded and compared between the two groups; as well as the changes of imaging indexes at last follow-up, and the clinical function score and ROM of metatarsophalangeal joint before operation, at 6 weeks after operation, and at last follow-up. Results: All patients were followed up 11-31 months, with an average of 22 months. The incision length and intraoperative blood loss in the minimally invasive group were significantly less than those in the traditional group ( P<0.05), and the intraoperative fluoroscopy frequency and operation time in the minimally invasive group were significantly more than those in the traditional group ( P<0.05); but no significant difference was found in weight-bearing walking time and fracture healing time between the two groups ( P>0.05). There was 1 case of skin injury in the minimally invasive group and 3 cases of poor incision healing in the traditional group; all patients had good healing at the osteotomy site, and no complication such as infection, nerve injury, or metatarsal head necrosis occurred. At last follow-up, the imaging indexes of the two groups significantly improved when compared with those before operation ( P<0.05). The changes of DMAA and TSP score in the minimally invasive group were significantly better than those in the traditional group ( P<0.05), and there was no significant difference in the changes of IMA, HVA, and forefoot width between the two groups ( P>0.05). The clinical scores and ROM of metatarsophalangeal joint significantly improved in the two groups at 6 weeks after operation and at last follow-up when compared with preoperative ones ( P<0.05), and the indicators in the minimally invasive group were significantly better than those in the traditional group ( P<0.05). Conclusion: Compared with traditional Chevron osteotomy, small incision external articular minimally invasive osteotomy can effectively improve HVA, IMA, and forefoot width, correct foot deformities, and has less trauma. It can better correct the first metatarsal pronation deformity and restore the anatomical position of the sesamoid bone, resulting in better effectiveness.
Subject(s)
Hallux Valgus , Minimally Invasive Surgical Procedures , Osteotomy , Humans , Osteotomy/methods , Minimally Invasive Surgical Procedures/methods , Hallux Valgus/surgery , Treatment Outcome , Range of Motion, Articular , Metatarsal Bones/surgery , Male , Female , Retrospective StudiesABSTRACT
The direct hydrogenation of greenhouse gas CO2 to higher alcohols (C2+OH) provides a new route for the production of high-value chemicals. Due to the difficulty of C-C coupling, the formation of higher alcohols is more difficult compared to that of other compounds. In this review, we summarize recent advances in the development of multifunctional catalysts, including noble metal catalysts, Co-based catalysts, Cu-based catalysts, Fe-based catalysts, and tandem catalysts for the direct hydrogenation of CO2 to higher alcohols. Possible reaction mechanisms are discussed based on the structure-activity relationship of the catalysts. The reaction-coupling strategy holds great potential to regulate the reaction network. The effects of the reaction conditions on CO2 hydrogenation are also analyzed. Finally, we discuss the challenges and potential opportunities for the further development of direct CO2 hydrogenation to higher alcohols.
ABSTRACT
This paper develops a multidimensional poverty index (MPI) evaluation system using multiple measures. We use the China Family Panel Study (CFPS) data to build balanced panel data from 2012 to 2018. Employing the probit model to analyze the impact of land transfer on relative poverty incidence, as well as utilizing the two-way fixed effects model and the logit model, we approach the issue from the perspective of multidimensional relative poverty identification. Our study indicates a decrease in relative poverty among rural households since 2012. Nonetheless, the overall incidence of relative poverty among rural households in China remains high at 20.6%, highlighting the severity of this issue in rural China. Moreover, we examine the heterogeneity of the poverty reduction effects of land transfer-in and land transfer-out. Land transfer can significantly reduce the incidence of relative poverty among rural households, with distinct mechanisms for land transfer-in and land transfer-out. Land transfer-in primarily reduces the relative poverty incidence of rural households through the education, housing, and land dimensions, while land transfer-out focuses on the quality-of-life dimension. Overall, land transfer-out has a more significant poverty reduction effect than land transfer-in. Furthermore, our study reveals that the reduction effect of land transfer on the incidence of relative poverty among rural households persists for at least two years, but by the fourth year, this effect disappears.
Subject(s)
Family Characteristics , Poverty , Humans , Rural Population , Educational Status , Employment , ChinaABSTRACT
Photocatalytic reduction of carbon dioxide is a technology that effectively utilizes CO2and solar energy. Sodium niobate (NaNbO3) has received much attention in the field of photocatalysis due to its excellent photocatalytic properties. However, the application of NaNbO3in the field of photocatalysis is still limited by poor reaction to visible light and easy recombination of photo-generated carriers. Heterojunction with g-C3N4to construct core-shell structure can effectively improve the above problems. Combining the two can design a core-shell composite material that is beneficial for photocatalytic reduction of CO2. Herein, we prepared a core-shell heterojunction g-C3N4/NaNbO3by uniformly impregnating urea on the surface of NaNbO3chromium nanofibers with NaNbO3nanofibers prepared by electrospinning as a catalyst carrier, and urea as a precursor of g-C3N4. The core-shell structure of g-C3N4/NaNbO3was verified by a series of characterization methods such as XPS, XRD, and TEM. It was found that under the same conditions, the methanol yield of core-shell g-C3N4/NaNbO3was 12.86µmol·g-1·h-1, which is twice that of pure NaNbO3(6.67µmol·g-1·h-1). This article highlights an impregnation method to build core-shell structures for improved photocatalytic reduction of CO2.
ABSTRACT
Perovskite-type LaFeO3 is regarded as a potentially efficient visible-light photocatalyst owing to its narrow bandgap energy and unique photovoltaic properties. However, the insufficient active sites and the unsatisfactory utilization of photogenerated carriers severely restrict the realistic application of pure LaFeO3. Herein, we fabricated a series of LaxFeO3-δ nanofibers (x = 1.0, 0.95, 0.9, 0.85, 0.8) with an A-site defect via sol-gel combined with the electrospinning technique. Wherein, the nonstoichiometric La0.9FeO3-δ possessed the highest CH3OH yield of 5.30 µmol·g-1·h-1 with good chemical stability. A series of advanced characterizations were applied to investigate the physicochemical properties and charge-carrier behaviors of the samples. The results illustrated that the one-dimensional (1D) nanostructures combined with the appropriate concentration of vacancy defects on the surface contributed to the radial migration of photogenerated carriers, inhibited the recombination of carriers, and provided more CO2 adsorption-activation sites. Furthermore, density functional theory (DFT) calculations were employed to reveal the influence mechanism of vacancy defects on LaFeO3. This work provides a strategy to enhance the performance of photocatalytic CO2 reduction by modulating the induced oxygen vacancies caused by the A-site defect in perovskite oxides.
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Objective: To measure the concentration of bone morphogenetic protein 2 (BMP-2) in demineralized bone matrix (DBM) prepared from different long bones and to evaluate the osteoinductivity of different DBM on MC3T3-E1 cells. Methods: Different bones from the same cadaver donor were used as the initial materials for making DBM, which were divided into ulna group (uDBM), humerus group (hDBM), tibia group (tDBM), and femur group (fDBM) according to the origins, and boiled DBM (cDBM) was taken as the control group. The proteins of DBM were extracted by guanidine hydrochloride, and the concentrations of BMP-2 were determined by ELISA assay. Then the DBM were co-cultured with MC3T3-E1 cells, the proliferation of MC3T3-E1 cells was observed by cell counting kit 8 (CCK-8) assay. The osteogenic differentiation ability of MC3T3-E1 cells was qualitatively observed by alizarin red, alkaline phosphatase (ALP), and Van Gieson staining, and the osteogenic differentiation ability of MC3T3-E1 cells was quantitatively analyzed by ALP content. Linear regression was used to analyze the effect of BMP-2 concentration in DBM on ALP synthesis. Results: There were significant differences in the concentration of BMP-2 among the DBM groups (P<0.05). The concentrations of BMP-2 in the lower limb long bone were higher than those in the upper limb long bone, and the concentration of BMP-2 in the fDBM group was about 35.5 times that in the uDBM group. CCK-8 assay showed that the cells in each group continued to proliferate within 5 days of co-culture, and the absorbance (A) values at different time points were in the order of cDBM groupSubject(s)
Bone Morphogenetic Protein 2
, Osteogenesis
, Alkaline Phosphatase
, Bone Matrix
, Cell Count
, Coloring Agents
, Animals
, Mice
ABSTRACT
The reduction of CO2 achieved by photocatalysis can simultaneously alleviate the energy crisis and solve environmental issues. Nevertheless, it remains challenging for the rational design of photocatalysts with high-efficiency carrier migration ability. Herein, the Z-scheme g-C3N4/In2O3 (CN/INO) heterostructure was fabricated via metal-organic frameworks (MOFs) assisted thermal deposition which could form a fully encapsulated hollow tubular structure. The unique structure was based on the MOFs-derived hollow hexagonal In2O3 tubular integrated with ultrathin g-C3N4. The Z-scheme CN/INO heterojunction exhibited a larger specific surface area and excellent charge separation efficiency. Benefiting from the above features, the Z-scheme CN/INO heterojunction demonstrated superior performance on photocatalytic CO2 reduction. The formation of CO and CH3OH over the optimized CN/INO-2 catalyst was 7.94 and 1.44 µmolâ g-1â h-1, respectively. Moreover, the density functional theory (DFT) calculations and Kelvin probe force microscopy (KPFM) was carried out to further investigate the situation of charge transfer on the interface of CN/INO. The in-situ Fourier transform infrared spectroscopy (FTIR) was measured to confirm the immediate products and the possible mechanism of photocatalytic CO2 reduction was proposed. This work provided a MOFs-assisted strategy to construct a Z-scheme system for photocatalytic CO2 reduction.
ABSTRACT
Drug selection and treatment monitoring via minimally invasive liquid biopsy using circulating tumor cells (CTCs) are expected to be realized in the near future. For clinical applications of CTCs, simple, high-throughput, single-step CTC isolation from whole blood without red blood cell (RBC) lysis and centrifugation remains a crucial challenge. In this study, we developed a novel cancer cell separation chip, "hybrid double-spiral chip", that involves the serial combination of two different Dean flow fractionation (DFF) separation modes of half and full Dean cycles, which is the hybrid DFF separation mode for ultra-high-throughput blood processing at high precision and size-resolution separation. The chip allows fast processing of 5 mL whole blood within 30 min without RBC lysis and centrifugation. RBC and white blood cell (WBC) depletion rates of over 99.9% and 99%, respectively, were achieved. The average recovery rate of spiked A549 cancer cells was 87% with as low as 200 cells in 5 mL blood. The device can achieve serial reduction in the number of cells from approximately 1010 cells of whole blood to 108 cells, and subsequently to an order of 106 cells. The developed method can be combined with measurements of all recovered cells using imaging flow cytometry. As proof of concept, CTCs were successfully enriched and enumerated from the blood of metastatic breast cancer patients (N = 10, 1-69 CTCs per 5 mL) and metastatic prostate cancer patients (N = 10, 1-39 CTCs per 5 mL). We believe that the developed method will be beneficial for automated clinical analysis of rare CTCs from whole blood.
Subject(s)
Microfluidic Analytical Techniques , Neoplastic Cells, Circulating , Humans , Microfluidics , Cell Line, Tumor , Neoplastic Cells, Circulating/pathology , Cell Separation , Erythrocytes/pathologyABSTRACT
BACKGROUND: Vibrio vulnificus infections develop rapidly and are associated with a high mortality rate. The rates of diagnosis and treatment are directly associated with mortality. CASE PRESENTATION: We describe an unusual case of a 61-year-old male patient with chronic liver disease and diabetes who presented with a chief complaint of pain in both lower legs due to V. vulnificus infection in winter. Within 12 h of arrival, typical skin lesions appeared, and the patient rapidly developed primary sepsis. Despite prompt appropriate antibiotic and surgical treatment, the patient died 16 days after admission. CONCLUSION: Our case findings suggest that V. vulnificus infection should be suspected in patients with an unclear infection status experiencing pain of unknown origin in the lower legs, particularly in patients with liver disease or diabetes, immunocompromised status, and alcoholism.
Subject(s)
Diabetes Mellitus , Fasciitis, Necrotizing , Liver Diseases , Sepsis , Vibrio Infections , Vibrio vulnificus , Fasciitis, Necrotizing/complications , Fasciitis, Necrotizing/diagnosis , Humans , Leg , Male , Middle Aged , Pain , Sepsis/complications , Sepsis/diagnosis , Vibrio Infections/complications , Vibrio Infections/diagnosisABSTRACT
Based on the acid-base neutralization, the (1-methylimidazolium)(tetrazol-1-yl)borane was successfully synthesized by taking advantage of the acidity of the tetrazole and the basicity of the 1-methylimidazole borane complex. Through HRMS, NMR, and FT-IR, the structure of synthetic compounds was characterized in detail. Concerning about the (1-methylimidazolium)(tetrazol-1-yl)borane, it had an ignition-delay time of about 25 ms and a density specific impulse over 351 s·g/cm3, making it a suitable candidate for green hypergolic fuels. Moreover, it also demonstrated that introducing tetrazole into the borane could be an appropriate strategy to adjust the performance of the energy of those borane compounds.
Subject(s)
Boranes , Imidazoles , Spectroscopy, Fourier Transform Infrared , Tetrazoles/chemistryABSTRACT
OBJECTIVE: To evaluate the clinical efficacy of local infiltration anesthesia of ropivacaine combined with compound betamethasone for postoperative analgesia in patients with hallux valgus. METHODS: From September 2019 to December 2020, 48 patients with hallux valgus were treated surgically. According to different postoperative analgesia methods, the patients were divided into combined local infiltration group and intravenous analgesia pump group. There were 24 cases, in the combined local infiltration group including 2 males and 22 females;the age ranged from 21 to 78 years old, with an average of (58.3±7.7) years old;soft tissue release and chevron osteotomy were performed in 15 cases and metatarsophalangeal joint fusion in 9 cases;immediately after operation, 20 ml of ropivacaine combined with compound betamethasone mixed diluent was used for local infiltration anesthesia once. There were 24 patients in intravenous analgesia pump group, including 3 males and 21 females;the age ranged from 23 to 81 years old, with an average of(56.8±8.3) years old;soft tissue release and Chevron osteotomy were performed in 17 cases and metatarsophalangeal joint fusion in 7 cases;immediately after operation, intravenous analgesia pump was used for analgesia. The basic flow was 2 ml / h;the self control dose was 0.5 ml;and the locking time was 15 min. Visual analogue scale (VAS) was recorded at 12, 24, 48 and 72 hours after operation;and the VAS was recorded at 24 hours after operation. The occurrence of adverse drug reactions at 0 to 12 hours, 12 to 24 hours and 24 to 48 hours after operation were recorded;and the healing of incision was recorded. RESULTS: All patients were followed up, and the duration ranged from 14 to 17 days, with a mean of (14.60±0.92) days. There was significantdifference in VAS at 12, 24 and 48 hours between the combined local infiltration group and the intravenous analgesia pump group(P<0.05). There was no significant difference in VAS between the two groups 72 hours after operation (P>0.05). There was no significant difference in the number of adverse drug reactions between the two groups at 0 to 12 hours after operation (P>0.05);there was significant difference in the number of adverse drug reactions 12 to 24 hours after operation (P<0.05). No adverse drug reactions occurred in both groups 24 to 48 hours after operation. There was no significant difference in the grade of knife edge healing between the two groups after suture removal (P>0.05). CONCLUSION: Compared with intravenous analgesia pump group, ropivacaine combined with compound betamethasone can significantly reduce postoperative wound pain without increasing adverse drug reactions, and does not increase wound infection.
Subject(s)
Analgesia , Bunion , Hallux Valgus , Adult , Aged , Aged, 80 and over , Anesthesia, Local , Feasibility Studies , Female , Hallux Valgus/surgery , Humans , Male , Middle Aged , Pain, Postoperative/drug therapy , Young AdultABSTRACT
Nitrogen-doped hierarchical porous carbons with a rich pore structure were prepared via direct carbonization of the poly(ionic liquid) (PIL)/potassium ferricyanide compound. Thereinto, the bisvinylimidazolium-based PIL was a desirable carbon source, and potassium ferricyanide as a multifunctional Fe-based template, could not only serve as the pore-forming agent, including metallic components (Fe and Fe3C), potassium ions (etching carbon framework during carbonization), and gas generated during the pyrolysis process, but also introduce the N atoms to porous carbons, which were in favor of CO2 capture. Moreover, the hierarchically porous carbon NDPC-1-800 (NDPC, nitrogen-doped porous carbon) had taken advantage of the highest specific surface area, exhibiting an excellent CO2 adsorption capacity and selectivity compared with NDC-800 (NDC, nitrogen-doped carbon) directly carbonized from the pure PIL. Furthermore, its hierarchical porous architectures played an important part in the process of CO2 capture, which was described briefly as follows: the synergistic effect of mesopores and micropores could accelerate the CO2 molecules' transportation and storage. Meanwhile, the appropriate microporous size distribution of NDPC-1-800 was conducive to enhancing CO2/N2 selectivity. This study was intended to open up a new pathway for designing N-doped porous carbons combining both PILs and the multifunctional Fe-based template potassium ferricyanide with wonderful gas adsorption and separation performance.
ABSTRACT
The emission of soot and NOx is one of the most severe environmental issues, and the key factor is the development of catalysts in after-treatment systems. In this study, an innovative non-noble metal catalyst, named HKLSM, was fabricated by etching 3DOM La0.8Sr0.2MnO3 with citric acid and synchronously anchoring potassium salt, for soot and NOx simultaneous removal. The citric acid could not only slightly erode the 3DOM skeleton, thereby beneficial to the dispersion of potassium, but also react with high-valence state Mn to generate abundant coordination unsaturated Mn3+ sites, which could produce more active oxygen species. Moreover, HKLSM showed a higher NOx adsorption capability than the samples that were not subjected to acid etching. This adsorbed NOx could be stored as NO3- species, which could facilitate soot combustion. Among all the as-prepared catalysts, HKLSM demonstrated a competitive soot combustion activity with a T50 value of 368 °C, a TOF value of 3.24 × 10-4 s-1, a reaction rate of 1.87 × 10-7 molg-1s-1, a total NOx to N2 yield of 42.0% and favorable reusability and water-resistance. This integration strategy can rationalize an alternative protocol to soot and NOx simultaneous elimination or even other catalysis systems.
ABSTRACT
As potential hypergolic fuels, hypergolic ionic liquids have attracted much attention since their development. Herein, a series of hypergolic ionic liquids based on asymmetric [bis(imidazolyl)-BH2]+ cations were synthesized. The asymmetric structure of these hypergolic ionic liquids was further confirmed by NMR, infrared (IR), and high-resolution mass spectrometry-electron spray ionization (HRMS-ESI). Moreover, these hypergolic ionic liquids possess a high density of over 1.00 g cm-3, a comprehensive liquid range from -60 °C to 20 °C, and a density-specific impulse performance ranging from 305.4 to 357.8 s g cm-3, which is superior to that of unsymmetrical dimethylhydrazine. Remarkably, (1-allyl-1H-imidazol-3-ium-1-yl)(1-methyl-1H-imidazol-3-ium-1-yl) dihydroboronium dicyandiamide had the best ignition-delay time (18 ms), a high density (1.114 g cm-3), and a high value for heat of formation (400 kJ mol-1/1.48 kJ g-1). This work provides the possibility of a promising and green hypergolic fuel as rocket propellant.
ABSTRACT
The construction of porous perovskite nanotubular materials with a good intrinsic activity, as well as a greater dispersion of the active sites is an effective strategy to obtain a high-performance catalyst used in soot removal. Thence, macro-mesoporous Co3O4-La0.88Sr0.12CoO3-δ nanotubes with large specific surface area (154.4 m2·g-1) from the acid etching of the porous La0.6Sr0.4CoO3-δ nanotubes, are supported by 5% K through bubbling method following calcination for soot combustion. The relationship between the specific surface area and K dispersion and their effect on the activity are studied by a series of isothermal kinetic measurements combined with the characterizations and activity evaluation results. It can be found that the greater the amount is of K+ incorporated into perovskite lattice, the better the dispersion of K, as well as the La2O2CO3 formed on the catalyst surface, thus leading to the enhanced performance in the soot catalytic combustion. As a result, the 5% K supported macro-mesoporous Co3O4-La0.88Sr0.12CoO3-δ nanotubes after acid etching show good activity and stability, where the T50 is 338 °C (5% O2 + 500 ppm NO + 6% H2O) with a good CO2 selectivity (above 99%), the activate energy is 78.1 kJ·mol-1, and the turnover frequency is 5.14 × 10-4 s-1.
ABSTRACT
Phosphorus-doped g-C3N4/ZnIn2S4 (PCN/ZIS) heterojunction photocatalysts were constructed by solvothermal method. The physical and chemical properties were investigated with X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), etc. The degradation of antibiotic wastewater was used to investigate the photocatalytic activities of composites under visible-light irradiation. The 10% PCN/ZIS had the best photocatalytic degradation performance for tetracycline with a photodegradation rate of 0.0874 min-1, which is respectively about 2.9 and 52.0 times than that of pure ZIS and PCN. Meanwhile, it was concluded that the holes and â O2- (superoxide radicals) play dominant roles in the photocatalytic reactions through radicals trapping experiments, while â OH (hydroxyl radicals) has a negative effect. In addition, 10%PCN/ZIS, with excellent stability and recyclability, also exhibited high photocatalytic activity for terramycin, chlortetracycline and ofloxacin. Overall, with the enhanced photocatalytic performance, PCN/ZIS could be potentially applied for photocatalytic degradation of antibiotic wastewater.
Subject(s)
Doping in Sports , Wastewater , Anti-Bacterial Agents/pharmacology , Catalysis , PhosphorusABSTRACT
Noninvasive detection of circulating fetal cells carrying the entire fetal genome is a promising way for prenatal testing of genetic diseases. However, ideal approaches for efficient separation of these valuable cells are not available. Here, a novel inertial microfluidic chip (CelutriateChip 1) is developed for ultra-fast, label-free enrichment of circulating trophoblasts (CTBs) from the whole blood samples of pregnant women. The unique structural design of the four-stage curved channel in CelutriateChip 1 enables CTBs with larger size to be efficiently separated from the blood samples under the effect of inertial and Dean drag forces. The transition of the target cells among the stages enables CelutriateChip 1 to achieve one or two orders of magnitude higher throughput compared to single channel inertial microfluidic chips. After optimization of conditions, CTBs can be recovered from 2 mL of whole blood within 5 min with an average recovery efficiency ranging from 52.3% to 65.8% and high white blood cell depletion (99.95%). CTBs collected from the chip can be isolated at the single-cell level and used for downstream immunofluorescence staining and genetic genotyping. Clinical tests are performed on 30 pregnant women and the results demonstrate that CTBs are obtainable in 86.67% of pregnancy cases. A single-base variant in the HBB gene can be accurately detected by sequencing of rare CTBs. This simple, antibody-free and low-cost approach holds promise for obtaining rare CTBs for prenatal detection of various genetic diseases.
Subject(s)
Microfluidic Analytical Techniques , Noninvasive Prenatal Testing , Cell Separation , Female , Fetus , Humans , Lab-On-A-Chip Devices , Pregnancy , Single-Cell Analysis , TrophoblastsABSTRACT
The porous perovskite-type La0.6Sr0.4CoO3-δ nanotubes are synthesized by sol-gel method combined with electrospinning technique following the calcination, while the porous nanotubular structure can increase the utilization of active sites related to the catalytic activity in soot oxidation. In order to further improve the catalytic activity, porous La0.6Sr0.4CoO3-δ nanotubes are further treated with nitric acid to obtain a larger specific surface area in this work. The as-prepared catalysts are characterized by different techniques to study their physical and chemical properties. The soot catalytic activity is evaluated by the temperature programmed oxidation tests and the values of activation energy. Based on the characterizations and catalytic activity evaluation, the correlation between the specific surface area and catalytic activity is well revealed by the isothermal kinetic measurements. The higher specific surface area (more than 150.0 m2 g-1) contributes to a larger amount and a better dispersion of the active oxygen species, thence improving the catalytic activity of soot oxidation. As a result, porous perovskite-type La0.6Sr0.4CoO3-δ nanotubes after nitric acid treatment for 4 h have the best activity and a good stability, with the T50 of 442 °C (5% O2) and 415 °C (5% O2 + 500 ppm NO), and the Ea of 93.6 kJ mol mol-1.
ABSTRACT
Clay-based aerogel is a promising material in the field of thermal insulation and flame retardant, but obtaining clay-based aerogel with high fire resistance, low thermal conductivity, hydrophobicity, and mechanical robustness remains a challenge. In this work, palygorskite-based aerogel was successfully fabricated via combining with a very small proportion of alginate to form a distinctive hierarchically meso-microporous structure. By employing ethanol solution (EA) replacement method and freeze-drying process, the resultant aerogel exhibited ultralow density (0.035-0.052 g/cm3), practical mechanical strengths (0.7-2.1 MPa), and low thermal conductivity of 0.0332-0.165 W/mK (25-1000 °C). The hydrophobicity of aerogel was achieved by simple chemical vapor deposition of methyltrimethoxysilane (MTMS). The Pal-based aerogel showed good performance in both fire resistance with high limiting oxygen index up to 90%, and heat resistance with tolerance of flame up to 1000 °C for 10 min. This renewable Pal-based aerogel with a 3D framework is a promising material to be applied in fields of construction and aerospace for thermal insulation and high fire resistance.