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Increasing the operating lifetime of green phosphorescent OLEDs by inserting a thin layer of TCTA to reduce charge accumulation at the interface is reported.

The luminance degradation ratio and the corresponding relative change of the exciton lifetimes for different hosts in the resulting yellow PhOLEDs.

In order to study the matching relationship between polymer(HPAM) molecular weight and reservoir permeability, in this paper, the injection performance of polymers with different molecular weights in rock cores with different permeability is studied. Using nuclear magnetic resonance technology combined with conventional core displacement equipment, the change law of the displacement process was analyzed from three aspects of nuclear magnetic resonance T2 spectrum, core layering, and imaging. Finally, the fluidity of the polymer solution in the core was analyzed by injection pressure control features. The experimental results show that the polymer solution with a molecular weight of 25 million has the best retention effect in the core flooding experiment and can stay in the dominant channel of the core for a long time to control the water flooding mobility. In rocks with a permeability of 500, 1000, and 2000 mD, subsequent water flooding can expand the swept volume by about 25% compared with polymer flooding. This method can effectively establish the adaptability matching relationship between the polymer molecular weight and the reservoir permeability.

To study the degradation of tetracycline by Bi2S3-based binary composite and ternary composite photocatalysts, Cu2O/Bi2S3 and NH2-UiO-66/BiOBr/Bi2S3 was successfully fabricated by the solvothermal ...

To study the degradation of bisphenol A (BPA) of the different Bi2WO6-based composite photocatalyst under visible-light irradiation, a novel Z-scheme Cu2S/reduced graphene oxide/Bi2WO6 (Cu2S/RGO/Bi...

In recent years, visualization technology based on magnetic resonance imaging has been widely used in core flooding experiments and mechanism research. In this research, the visualization of produced oil is realized by subtracting from image signals collected in different displacement stages. The distribution images of the produced oil can be used to clearly analyze the oil displacement characteristics of cores with different permeabilities and chemical agents with different functions. The distribution image of the produced oil shows advantageous and hard-to-reach areas of water flooding in cores with different permeabilities. The SMG dispersion by blocking the dominant water pathway produced remaining oil areas that were difficult to be swept water flooding and then enlarged the swept volume. The produced oil is concentrated at both ends and dispersed in the middle of the core. The polymer flooding by improving the viscosity of water flooding sharply increased the injection pressure and then swept all areas. The distribution image of the produced oil has the characteristics of filamentous continuous advancement.

This paper investigates the change in size and morphology of the silica network with the change of water content by sol-gel method. Methyl triethoxysilane (MTES) and tetraethyl orthosilicate (TEOS) were used as co-precursors. The results reveal that the morphology controllable silica network are prepared by changing water content, the size of silica network is in the range in 17–176 nm. There are two ways for the silica nanoparticles to grow in the sol media, condensing with the newly hydrolyzed precursor named monomer-addition model or condensing with the existing silica structure called controlled-aggregation model. As the molar ratio of water/siloxane increases from 1 to 12, the growth process change from the aggregation of oligomers to the condensation between oligomer and hydrolyzed precursor, and the final morphology of silica nanoparticles changes from a network structure to a monodisperse particle structure. When the water content reaches a very high value with the molar ratio of water/siloxane ≥12, the growth process of silica nanoparticles is dominated by the monomer-addition mechanism. The addition of MTES as co-precursor favors the formation of the network structure.

We present a new type of ultra-low refractive index antireflective (AR) coating based on spherical-chain silica particle with super-hydrophobic surface. This AR coating is fabricated using methyltriethoxysilane (MTES) and ethylsilicate (TEOS) as co-precursors to direct silica particles to form a spherical-chain structure. Then hexamethyldisilazane (HMDS) was further used to modify the surface of spherical-chain silica particle, which greatly decreases the refractive index of the silica thin film from 1.139 to 1.098. The formation mechanism of the ultralow refractive index thin film is proposed. The spherical-chain silica particle surface modification with HMDS significantly improves the hydrophobicity of the coated film; the water contact angle of the film increases from 42° to 168°. Ultimately, using this hydrophobic ultralow-index coating as a top-layer, a high-performance double-layer antireflective coating was fabricated with self-cleaning, environmental resistance and a high average transmittance of 99.64% in the wavelength range of 400–800 nm. This multi-functional broadband antireflective coating has potential value in the field of solar cells.

It is strongly desired to design and synthesize amphiphilic nanoreactors with tunable compatibility, which are stable at the biphasic interface in both acidic and alkaline environments. Herein, a novel amphiphilic R

Antireflective (AR) coatings can suppress the undesired interfacial Fresnel reflections, and they are widely used in optical devices and energy-related instruments. Conventional single-layer AR coatings, which only work at a single wavelength, encounter serious limitations in some practical applications because of their inherent properties. In this paper, λ/4–λ/4 double-layer antireflective (AR) coatings with constant high transmittance in a pre-determined wavelength range was prepared by the sol–gel method via acid-catalyzed and base-catalyzed SiO2 thin films. A double-layer antireflective coating with an almost constant transmittance value of 99.8% in the range of 550–700 nm was obtained, and the transmittance of this coating was higher than 99% in a wider range of 450–850 nm with a fluctuation of less than 1%. The coatings had good environmental stability and maintained constant high transmittance after two weeks of exposure in 50% humidity. The broadband AR coatings may have important applications in fields such as electroluminescent display.

Experiment and molecular dynamics simulation were carried out to study the tunable stability of oil-containing SDS-stabilized Nitrogen-in-water foam. The experimental results show that the foam stability could be tuned by the concentrations of SDS and modified SiO2 nanoparticles. In the foam systems with a low SDS concentration (0.2 wt.%), the foams show poor stability and the foam stability was almost not affected by the addition of modified SiO2 nanoparticles. The foam stability was greatly improved at moderate SDS concentration (0.5 wt.%), it enhanced first and then weakened with the increase of modified SiO2 concentration, and the half-life time achieved a maximum value of 1292 s at 0.05 wt.% modified SiO2. However, at high SDS concentration (0.8 wt.%), the foam stability was pretty good except for when the modified SiO2 concentration is too high (>0.2 wt.%). The microscopic mechanism was obtained by investigating the structural and dynamic properties of the foam film. The simulation work showed consistent results of foam stability with the experimental results. Moreover, it also revealed that the concentration and configuration of SDS will affect its interaction with SiO2 and oil molecule, which is critical to foam stability.

In the process of realizing double-wavelength broadband antireflection (AR) coatings, it is very important to control the refractive index in a wide range, but at present, many methods of adjusting the refractive index are too complex or expensive. Here, a simple and inexpensive sol–gel route is proposed to prepare the superhydrophilic silica (SiO2) thin films having ultra-low refractive indices by the SiO2 particles surface corrosion with hydrofluoric acid (HF) in sol; this treatment effectively reduces the refractive index of the coating from 1.22 to 1.11. The formation mechanism of the coatings with ultra-low refractive index was discussed in detail. The corrosion of HF on the particles surface significantly improves the hydrophilicity of the coating, and reduces the water contact angle of the coating from 27° to 2°. The bottom layer is prepared by mixing the acid–base complex silica sol. When the refractive indices of the bottom and top layers were set as 1.29 and 1.13, the double-layer double-wavelength AR coating with excellent optical properties has the transmittance of 99.95% and 100.00% at 532 and 1064 nm, respectively.

Cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) extracted from renewable resources possess many attractive characteristics, making them ideal Pickering emulsion stabilizers. However, unmodified pristine CNCs with high surface charge density are not effective in stabilizing oil–water emulsions, thereby limiting their application as interfacial stabilizers. Grafting hydrophobic polymers onto CNCs enhanced their wettability by the oil phase, which reduced the interfacial tension. Thus, hydrophobic modification was performed by grafting cinnamoyl chloride or butyryl chloride to the surface of CNFs. The modified CNFs were further hydrolyzed for 1 or 2 h to produce nanocellulose of varying sizes and hydrophobicity, and they were effective Pickering emulsifiers. The effect of nanocellulose concentration, polarity of solvents, hydrophobicity, size and electrolyte on the characteristics of the Pickering emulsions were examined and elucidated.

Organic reactors in a green solvent (water) is the goal of sustainable development. Green nanoreactors with excellent amphiphilicity and catalytic activity are strongly desired. Herein, a novel amphiphilic nanoreactor Pd@amZSM-5 with ultrasmall size has been successfully synthesized via a simple one-step oil bath method, subjected to the modification-etching-modification strategy and in situ reduction of Pd2+. Ultrasmall Pd@amZSM-5 nanoreactors (60 nm) with hierarchical structures showed outstanding amphiphilicity for forming Pickering emulsions with fine uniform droplets (50 μm). Fine droplets formed short diffusion distances, which can significantly improve the catalytic activity in biphasic reactions. Moroever, the ultrasmall Pd@amZSM-5 nanoreactors demonstrated excellent catalytic activity for the selective oxidation of alcohols in water using air as the oxidant. Alkali was not present in the reaction system. The hydrophilic aminopropyl groups on the surface of the Pd@amZSM-5 nanoreactors not only changed the affinity of the zeolite surface and provided targeting points for Pd nanoparticles but also provided an alkaline environment for the selective oxidation of alcohols. The ultrasmall Pd@amZSM-5 nanoreactors presented excellent universality for aromatic alcohols (with >90% conversion and >90% selectivity) and allylic alcohols (with 100% conversion and 100% selectivity).

The preparation and classification of nanocellulose are briefly introduced, and the modification of nanocellulose and the application of modified nanocellulose in oilfield chemistry are reviewed. The principles and methods of surface modification, including surface adsorption, oxidation, acetylation, silanization, etherification, and polymer grafting, are summarized. Meanwhile, this paper focuses on the application of nanocellulose research progress in drilling fluid, enhanced oil recovery, and oilfield sewage treatment. In addition, the application issues and natural advantages of nanocellulose are analyzed, and suggestions and ideas on how to expand its application are put forward. Finally, the development and potential application of nanocellulose in oilfield chemistry are proposed.

Aim: Intensity-modulated radiotherapy (IMRT) is a widely accepted therapy for nasopharyngeal carcinoma (NPC), but it inevitably brings out radiation-related complications and seriously affects the quality of life (QoL). Endoscopic nasopharyngectomy (ENPG) has been successfully conducted in locally recurred NPC, but few studies evaluated its application in early NPC. This study aims to assess the feasibility and safety of ENPG combined with low-dose radiotherapy (LDRT) in T1-2 NPC. Patients and Methods: We recruited 37 newly diagnosed localized T1-2 NPC patients who voluntarily accepted ENPG +LDRT from June 2013 to September 2016. Meanwhile, the data of 132 T1-2 NPC patients treated with IMRT were collected and used as control group. The survival outcomes, QoL score and late RT-related sequelaes were compared between the 2 groups. Results: After a median follow-up of 54 months, only 1 patient in ENPG+LDRT group died along with hepatic metastases. The 5-year overall survival, distant metastasis-free survival, local relapse-free survival and regional relapse-free survival in ENPG+LDRT group were 97.3%, 97.3%, 100% and 100%, which were not statistically different from the control group (97.7%, 90.2%, 95. 5%, 97.0%, respectively, all P > 0.05). In comparison with IMRT group, ENPG+LDRT exhibited better QoL and less rate of late RT-related sequlaes including hearing loss (53.8% vs 27.0%, P = 0.005), xerostomia (46.2% vs 24.3%, P = 0.023) and dysphagia (25.8% vs 8.1%, P = 0.024). Conclusions: ENPG+LDRT provided satisfactory survival outcomes, and improved the QoL and reduced the incidence of sequelae for T1-2 NPC patients.

The 8-oxo-deoxyguanosine is the most abundant specie of the DNA oxidative damage. Despite the deleterious effects such as gene mutation it may cause, the 8-oxodG was also reported to have beneficial effect such as repairing the nearby cyclobutane pyrimidine dimer (CPD) after photoexcitation. Due to its strong biological relevance, the photoinduced excited state dynamics behavior of 8-oxo-deoxyguanosine is of particular interest. In this work, a theoretical investigation by combination of complete active space self-consistent field (CASSCF) ab initio calculations and on-the-fly nonadiabatic dynamics simulations are implemented to provide intrinsic deactivation mechanism of its free base 8-oxoguanine after being excited to the S

This paper summarizes the latest achievements and technological progress in oil and gas production engineering of China National Petroleum Corporation (CNPC) and discusses the main four challenges faced: developing low quality resource at low oil price; keeping stable production of mature oilfields when well oil production drops year by year; low systematic efficiency, high cost, prominent environmental protection issue and short of technological strategy for high water cut ratio and high oil recovery ratio oilfields; and lacking of high level horizontal well drilling and completion technology to develop unconventional and deep reservoirs. Three technological development directions to address these challenges are put forward: developing fracture controlling stimulation and well factory to produce low quality resource economically, developing re-fracturing technology for old wells in mature oilfields, promoting the fourth generation separate layer water injection technology to stabilize the production of mature oilfields; innovating new technologies of water flooding with nano-material, injecting and producing through one well. Key words: China oil and gas production, oil and gas production engineering, technological achievement, technological challenge, future direction, advanced technology

Cell therapy has emerged as a promising new treatment in medicine, which is expected to be able to cure diseases by repairing, replacing, and regenerating tissues, as well as through immune modulation. However, challenges remain in ensuring consistent quality, clinical efficacy, and safety profiles because of the diversity of cell types and clinical indications for cell therapy products (CTPs), as well as different and complex manufacturing process. Therefore, scientific consensus and regulatory measurements are urgently warranted to promote the translation of the latest scientific advances and innovative manufacturing technologies into clinical application. This article aims to propose perspectives on the manufacturing, quality study, and quality control of CTPs and provide considerations and opinions in the regulation of CTPs.

Engineering the shape of nanoparticles has emerged as an effective approach for optimizing their physical/chemical properties. In particular, two-dimensional (2D) nanostructures with their high surface area/volume ratio have opened up exciting opportunities for developing advanced anisotropic materials and facilitating chemical processes that demand high levels of surface interactions. Although the great potential of low-dimensional 2D nanoswimmers has been suggested by theoretical works, very little experimental study has been undertaken thus far. Here we fabricated a low-dimensional magnetic nanomotor based on discotic barium ferrite nanoplates. We demonstrated that the “fuel-to-motion” behavior and the enhanced diffusion of nanoswimmers are not limited to just 0D nanospheres or 1D nanorods but are also applicable to 2D nanoplates. In addition, the 2D nanoswimmers showed excellent catalytic performance in removing molecular and particle stains on cloth likely due to their catalytic activity as well as a...