Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pr...Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pressure,complicated structure and anisotropic,high flow-resistance and micro pore throats etc,.Generally they also have lots of natural micro fractures,probably leading to stress sensibility.Main damaging factors in such reservoirs are water-sensibility and water-blocking caused by invasive fluids during drilling and production operations.Once damaged,formation permeability can rarely recovered.Numerous studies have shown that damaging extent of water-blocking ranges from 70% to 90%.Main damaging mechanisms and influencing factors of water-blocking were systematically analyzed.Also some feasible precaution or treating approaches of water-blocking were put forward.In a laboratory setting,a new multi-functional drilling fluid composed mainly of amphion polymer,sulfonation polymer,high effectively preventive water-blocking surfactants,ideal packing temporary bridging agents(TBA) and film-forming agents,etc.,were developed.New low-damage drilling fluids has many advantages,such as good rheological properties,excellent effectiveness of water-blocking prevention,good temporary plugging effect,low filtration and ultra-low permeability(API filtration≤5 mL,HTHP filtration≤10 mL,mud cake frictional coefficient≤0.14,permeability recovery>81%),can efficiently prevent or minimize damage,preserve natural formation and enhance comprehensive development-investment effect in TUHA Jurassic dense sandstone reservoir formation with low-permeability,the only one developing integrated condense gas field.Some references can be provided to similar reservoir formations.展开更多
The morphology of active layer in bulk heterojunction(BHJ) organic solar cells is decisive to the device performance. Previous works have shown that the solvent engineering is an effective method to optimize the morph...The morphology of active layer in bulk heterojunction(BHJ) organic solar cells is decisive to the device performance. Previous works have shown that the solvent engineering is an effective method to optimize the morphology of active layer. However, screening the proper solvent is a tedious task, and we know very little about how to select a proper solvent for a particular system, especially for polymer/nonfullerene blend systems. Here, we combined the spectroscopic analysis in various solvent mixtures during film-forming process to reveal the relationship among the cosolvent characteristics, film-forming kinetics and film morphology. In this article, P3 HT/O-IDTBR blend was selected as model system due to being facile synthesized under a large-scale. Chlorobenzene(CB) was selected as main solvent, and the cosolvents were grouped into three categories according to its boiling point(bp) compared to CB.The cosolvents with lower bp, like chloroform(CF), can facilitate a faster film-forming process, reducing the domain size but sacrificing the crystallinity of both components. For the cosolvents with higher bp,like o-dichlorobenzene(DCB) and 1,2,4-trichlorobenzene(TCB), the self-organization process of P3 HT and O-IDTBR is separated and its duration was extended, constructing highly crystalline nanointerpenetrating network. However, the cosolvents with very high bp, such as chlornaphthalene(CN),would residue in film and keep P3 HT and O-IDTBR self-organizing for longer time, leading to larger phase separation. This work systematically investigated the effect of cosolvent on the film-forming kinetics, and proposed a guideline of how to select a proper cosolvent according to the crystallinity and domain size of active layer.展开更多
There is currently no consensus regarding the management of acute cutaneous reactions emerging from a concurrent treatment of radio-and chemotherapy, the goal of this case study series is to provide scientific evidenc...There is currently no consensus regarding the management of acute cutaneous reactions emerging from a concurrent treatment of radio-and chemotherapy, the goal of this case study series is to provide scientific evidence based on clinical practice regarding the efficacy of a film-forming wound dressing for patients receiving combined cancer therapy, in particular examples where the reactions are expected to be intense. In all the described cases, management of acute skin reactions allowed the cancer therapy to be finalized, instead of being interrupted due to an increase in the severity of the reactions. It has been shown in the current literature that the lack of compliance with treatment plans correlates with poorer clinical outcome. Evidence from the cases presented suggest that the studied dressing is safe and efficacious in the treatment and the prevention of acute cutaneous reactions arising from combined cancer therapy.展开更多
Electrolytes additives are ubiquitous and indispensable in all electrochemical devices. In this sense, the principle and the classification of film-forming additives for lithium ion secondary batteries are described. ...Electrolytes additives are ubiquitous and indispensable in all electrochemical devices. In this sense, the principle and the classification of film-forming additives for lithium ion secondary batteries are described. The film formation mechanism and research progress of the pyrazole derivatives, organic halogenide, esters and derivatives, boron compounds and inorganic compounds are introduced. Emphasis is focused on the principles and film-forming mechanisms of each additive. The development of film-forming additives is forecasted and prospected.展开更多
The skin is the most extensive and outermost organ in the body and can be greatly exploited both from the point of view of alternative routes of systemic drug delivery and treatment of dermatological diseases. Because...The skin is the most extensive and outermost organ in the body and can be greatly exploited both from the point of view of alternative routes of systemic drug delivery and treatment of dermatological diseases. Because of its main function as a barrier against harmful external agents, it also becomes a barrier to drug administration, but there are strategies to reduce this limitation of this promising route of administration. The development of polymer-based film-forming formulations is extensively studied for this purpose, since the formation of a film on the skin increases the contact time of the drug, for this being characterized as a controlled release reservoir system. There are a multitude of possible polymers to compose these formulations and their choice must be made according to the purpose of each application. This work, therefore, aims to study the state of the art of film forming systems for topical application of pharmaceutical formulations.展开更多
In order to improve the plugging and anti-collapse performance of water-based drilling fluid,a polymer film-forming plugging agent LWFD is synthesized by emulsion polymerization.The effect of the agent on rheology,API...In order to improve the plugging and anti-collapse performance of water-based drilling fluid,a polymer film-forming plugging agent LWFD is synthesized by emulsion polymerization.The effect of the agent on rheology,API filtration loss,lubricity and film plugging of polymer drilling fluid and cationic drilling fluid is evaluated in laboratory.The experimental results show that the agent has little effect on the rheology and filtration loss of polymer drilling fluid and cationic drilling fluid,and can improve the lubricity of drilling fluid.The synthesized polymer film-forming plugging agent LWFD has good plugging properties for sand discs with different permeabilities,and the agent can effectively improve the film-forming plugging and temperature resistance of drilling fluid when combined with the inorganic nano-plugging agent NMFD.The high performance polymer drilling fluid formed by introducing polymer film-forming plugging agent LWFD and inorganic nano-plugging agent NMFD into polymer drilling fluid has comparable performance as Halliburton’s SHALEDRIL high performance drilling fluid,which can meet the requirements of on-site drilling and has application value.展开更多
A method combining computationalfluid dynamics(CFD)and an analytical approach is proposed to develop a prediction model for the variable thickness of the spray-induced liquidfilm along the surface of a cylindrical workp...A method combining computationalfluid dynamics(CFD)and an analytical approach is proposed to develop a prediction model for the variable thickness of the spray-induced liquidfilm along the surface of a cylindrical workpiece.The numerical method relies on an Eulerian-Eulerian technique.Different cylinder diameters and positions and inclinations of the spray gun are considered and useful correlations for the thickness of the liquidfilm and its distribution are determined using various datafitting algorithms.Finally,the reliability of the pro-posed method is verified by means of experimental tests where the robot posture is changed.The provided cor-relation are intended to support the optimization of spray-based coating applications.展开更多
Pharmaceutical scientists throughout the world are trying to explore thin films as a novel drug delivery tool. Thin films have been identified as an alternative approach to conventional dosage forms. The thin films ar...Pharmaceutical scientists throughout the world are trying to explore thin films as a novel drug delivery tool. Thin films have been identified as an alternative approach to conventional dosage forms. The thin films are considered to be convenient to swallow, selfadministrable, and fast dissolving dosage form, all of which make it as a versatile platform for drug delivery. This delivery system has been used for both systemic and local action via several routes such as oral, buccal, sublingual, ocular, and transdermal routes. The design of efficient thin films requires a comprehensive knowledge of the pharmacological and pharmaceutical properties of drugs and polymers along with an appropriate selection of manufacturing processes. Therefore, the aim of this review is to provide an overview of the critical factors affecting the formulation of thin films, including the physico-chemical properties of polymers and drugs, anatomical and physiological constraints, as well as the characterization methods and quality specifications to circumvent the difficulties associated with formulation design. It also highlights the recent trends and perspectives to develop thin film products by various companies.展开更多
This paper discusses the systematic design and development of low-damage drilling fluid to protect the low-permeability gas reservoir of the Sulige block in the Ordos Basin, Inner Mongolia Autonomous Region, China. Ba...This paper discusses the systematic design and development of low-damage drilling fluid to protect the low-permeability gas reservoir of the Sulige block in the Ordos Basin, Inner Mongolia Autonomous Region, China. Based on investigation of the geological characteristics and the potential formation damage of the Permian formation of the reservoir, waterblocking due to invasion of drilling or completion fluids was identified one of the most severe causes of damage to gas well deliverability. By adopting the phase trap prevention method, ideal packing theory, and film-forming technology, a lowdamage drilling fluid, sodium formate brine containing efficient waterblocking preventing surfactants, optimized temporary bridging agents (TBAs), and film-forming agents has been developed. The performance of the new drilling fluid was evaluated by using a variety of techniques. The results show that the fluid has good rheological properties, good strong shale-swelling inhibition, good temporary plugging effect, ultra-low filtration, and good lubricity. It can efficiently minimize waterblocking and can be used to drill horizontal wells with minimal intervention of the reservoir in the Sulige Gas Field.展开更多
For poly(9,9-dioctylfluorene)(PFO),β phase (coplanar conformation with the intra-chain torsion angle of 165°) has a greater conjugation length and higher degree of order compared to those of α phase, which favo...For poly(9,9-dioctylfluorene)(PFO),β phase (coplanar conformation with the intra-chain torsion angle of 165°) has a greater conjugation length and higher degree of order compared to those of α phase, which favors charge carrier transport. However, the highest content of β phase obtained so far is 45%. We propose to increase the content of β phase by promoting the solution aggregation of PFO molecules and extending film-forming time. For this purpose, 1,8-diiodooctane (DIO) is added to PFO o-xylene solution, which enhances the interaction of PFO chains and improves the planarity of PFO backbone, resulting in the formation of ordered aggregation. The aggregates act as nucleation centers to promote the formation of β phase. The content of β phase increases with increasing DIO concentration and reaches a platform of 39% as DIO is more than 4 vol%. Furthermore, the film is kept in a sealed environment with oxylene atmosphere for 3 h, thus the PFO molecules have enough time to diffuse to the crystallization front and achieve disorder-order transition. As a result, the crystallinity of PFO is improved significantly and the content of β phase increases to 52%, reaching the highest value reported so far.展开更多
Accurately obtaining the original information of an in-situ rock via coring is a significant guiding step for exploring and developing deep oil and gas resources.It is difficult for traditional coring technology and e...Accurately obtaining the original information of an in-situ rock via coring is a significant guiding step for exploring and developing deep oil and gas resources.It is difficult for traditional coring technology and equipment to preserve the original information in deep rocks.This study develops a technology for insitu substance-preserved(ISP),moisture-preserved(IMP),and light-preserved(ILP)coring.This technology stores the original information in real time by forming a solid sealing film on the in-situ sample during coring.This study designed the ISP-IMP-ILP-Coring process and tool.In addition,an ISP-IMP-ILPCoring process simulation system was developed.The effects of temperature,pressure,and film thickness on the quality of the in-situ film were investigated by performing in-situ film-forming simulation experiments.A solid sealing film with a thickness of 2-3 mm can be formed;it completely covers the core sample and has uniform thickness.The film maintains good ISP-IMP-ILP properties and can protect the core sample in the in-situ environment steadily.This study verifies the feasibility of“film formation during coring”technology and provides strong support for the engineering application of ISP-IMP-ILPCoring technology.展开更多
The present work firstly aimed to obtain cellulose from sugarcane bagasse by using alkaline methods in pulping/delignifying and, at bleaching stages, using sodium chlorite, glacial acetic acid, and hydrogen peroxide, ...The present work firstly aimed to obtain cellulose from sugarcane bagasse by using alkaline methods in pulping/delignifying and, at bleaching stages, using sodium chlorite, glacial acetic acid, and hydrogen peroxide, associated to NaOH/KOH. The process was carried out at temperatures varying from 55°C to 110°C, under magnetic stirring in various steps lasting from 2 h to 12 h. The yields of the two cellulose extracted, SCB24-Na-I and SCB24-Na-II, were 37% and 41%, respectively, from samples of ca. 15 g of the bagasse. Secondly, it is to extract nanoparticles from the obtained celluloses via acid hydrolysis (with 77% H2SO4) to lately be tested as reinforcement in biodegradable packagings. Both celluloses and their respective nanoparticles were characterized by several techniques, among them ATR-FTIR, DSC-TGA, XRD, SEM, and TEM. Despite that the yields of cellulose nanoparticles have been low, the preliminary studies of their use in biodegradable films coated on biodegradable pots were promising.展开更多
Fluorosurfactants are the key ingredients in the formulations of aqueous film-forming foams(AFFFs)for extinguishing flammable liquids,thus developing high-efficient and low-toxic fluorosurfactants is desirable in AFFF...Fluorosurfactants are the key ingredients in the formulations of aqueous film-forming foams(AFFFs)for extinguishing flammable liquids,thus developing high-efficient and low-toxic fluorosurfactants is desirable in AFFFs application.Herein,a series of hyperbranched polymeric fluorosu rfactants(HPFs)were successfully synthesized through sequentially modifying hyperbranched polyethylenimine(PEI)with the hydrophilic poly(ethylene glycol)(PEG)chains and the hydrophobic C6/C4-based perfluoroalkyl chains,which were verified by FTIR,^(1)H-and^(19)F-NMR.The surface tensions of all the HPFs in water were measured,and the corresponding physicochemical parameters were interpreted.It was found that the surface activities of HPFs could be tuned through adjusting the ratio of PEG to perfluoroalkyl chains,the length of perfluoroalkyl chains,the molecular weight of PEI core,but not the PEG chain length.In the binary mixture of HPFs with the commercial small molecule fluorosurfactant Capstone^(TM)1157(C1157),a strong synergism led to the elevation of surface activity,which was attributed to the efficient encapsulation of C1157 guests by the compact hyperbranched HPFs as the hosts.The utilization of HPF/C1157 as fluorosurfactant ingredients in AFFF formulations could realize much higher fire-extinguishing efficiency towards flammable oils than the control AFFFs prepa red from the polymeric Capstone^(TM)1460 or the neat C1157.展开更多
Three different types of new electrolyte additives were adopted as flame retardant to improve the safety of nickel-cobalt-aluminum(LiNi_(0.8)Co_(0.15)Al_(0.05)O_2, abbreviation NCA) based lithium batteries. By adding ...Three different types of new electrolyte additives were adopted as flame retardant to improve the safety of nickel-cobalt-aluminum(LiNi_(0.8)Co_(0.15)Al_(0.05)O_2, abbreviation NCA) based lithium batteries. By adding 5 wt% of the additives, an obvious flame retardant effect can be observed for the electrolyte. Furthermore,it was found that the additives can help for forming a stable cathode electrolyte interface(CEI) film on the NCA cathode, which are important for enhancing the thermal stability of the electrolyte and make the electrolyte obviously reduce the flammability, as well as good effect on the cycling cycle performance of the battery. These results indicate that our flame retardant are favorable additives in conventional liquid electrolytes for rechargeable lithium-ion batteries with good safety and high performances.展开更多
基金Project(50574061) supported by the National Natural Science Foundation of China
文摘Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pressure,complicated structure and anisotropic,high flow-resistance and micro pore throats etc,.Generally they also have lots of natural micro fractures,probably leading to stress sensibility.Main damaging factors in such reservoirs are water-sensibility and water-blocking caused by invasive fluids during drilling and production operations.Once damaged,formation permeability can rarely recovered.Numerous studies have shown that damaging extent of water-blocking ranges from 70% to 90%.Main damaging mechanisms and influencing factors of water-blocking were systematically analyzed.Also some feasible precaution or treating approaches of water-blocking were put forward.In a laboratory setting,a new multi-functional drilling fluid composed mainly of amphion polymer,sulfonation polymer,high effectively preventive water-blocking surfactants,ideal packing temporary bridging agents(TBA) and film-forming agents,etc.,were developed.New low-damage drilling fluids has many advantages,such as good rheological properties,excellent effectiveness of water-blocking prevention,good temporary plugging effect,low filtration and ultra-low permeability(API filtration≤5 mL,HTHP filtration≤10 mL,mud cake frictional coefficient≤0.14,permeability recovery>81%),can efficiently prevent or minimize damage,preserve natural formation and enhance comprehensive development-investment effect in TUHA Jurassic dense sandstone reservoir formation with low-permeability,the only one developing integrated condense gas field.Some references can be provided to similar reservoir formations.
基金supported by the National Natural Science Foundation of China (51773203, 51903211)the Fundamental Research Funds for the Central Universities (D5000200273)。
文摘The morphology of active layer in bulk heterojunction(BHJ) organic solar cells is decisive to the device performance. Previous works have shown that the solvent engineering is an effective method to optimize the morphology of active layer. However, screening the proper solvent is a tedious task, and we know very little about how to select a proper solvent for a particular system, especially for polymer/nonfullerene blend systems. Here, we combined the spectroscopic analysis in various solvent mixtures during film-forming process to reveal the relationship among the cosolvent characteristics, film-forming kinetics and film morphology. In this article, P3 HT/O-IDTBR blend was selected as model system due to being facile synthesized under a large-scale. Chlorobenzene(CB) was selected as main solvent, and the cosolvents were grouped into three categories according to its boiling point(bp) compared to CB.The cosolvents with lower bp, like chloroform(CF), can facilitate a faster film-forming process, reducing the domain size but sacrificing the crystallinity of both components. For the cosolvents with higher bp,like o-dichlorobenzene(DCB) and 1,2,4-trichlorobenzene(TCB), the self-organization process of P3 HT and O-IDTBR is separated and its duration was extended, constructing highly crystalline nanointerpenetrating network. However, the cosolvents with very high bp, such as chlornaphthalene(CN),would residue in film and keep P3 HT and O-IDTBR self-organizing for longer time, leading to larger phase separation. This work systematically investigated the effect of cosolvent on the film-forming kinetics, and proposed a guideline of how to select a proper cosolvent according to the crystallinity and domain size of active layer.
文摘There is currently no consensus regarding the management of acute cutaneous reactions emerging from a concurrent treatment of radio-and chemotherapy, the goal of this case study series is to provide scientific evidence based on clinical practice regarding the efficacy of a film-forming wound dressing for patients receiving combined cancer therapy, in particular examples where the reactions are expected to be intense. In all the described cases, management of acute skin reactions allowed the cancer therapy to be finalized, instead of being interrupted due to an increase in the severity of the reactions. It has been shown in the current literature that the lack of compliance with treatment plans correlates with poorer clinical outcome. Evidence from the cases presented suggest that the studied dressing is safe and efficacious in the treatment and the prevention of acute cutaneous reactions arising from combined cancer therapy.
文摘Electrolytes additives are ubiquitous and indispensable in all electrochemical devices. In this sense, the principle and the classification of film-forming additives for lithium ion secondary batteries are described. The film formation mechanism and research progress of the pyrazole derivatives, organic halogenide, esters and derivatives, boron compounds and inorganic compounds are introduced. Emphasis is focused on the principles and film-forming mechanisms of each additive. The development of film-forming additives is forecasted and prospected.
文摘The skin is the most extensive and outermost organ in the body and can be greatly exploited both from the point of view of alternative routes of systemic drug delivery and treatment of dermatological diseases. Because of its main function as a barrier against harmful external agents, it also becomes a barrier to drug administration, but there are strategies to reduce this limitation of this promising route of administration. The development of polymer-based film-forming formulations is extensively studied for this purpose, since the formation of a film on the skin increases the contact time of the drug, for this being characterized as a controlled release reservoir system. There are a multitude of possible polymers to compose these formulations and their choice must be made according to the purpose of each application. This work, therefore, aims to study the state of the art of film forming systems for topical application of pharmaceutical formulations.
基金Project of National Natural Science Foundation of China“Research on Shale Wellbore Stability and Fracture Mechanism under Shale Gas Development Conditions”(51174036).
文摘In order to improve the plugging and anti-collapse performance of water-based drilling fluid,a polymer film-forming plugging agent LWFD is synthesized by emulsion polymerization.The effect of the agent on rheology,API filtration loss,lubricity and film plugging of polymer drilling fluid and cationic drilling fluid is evaluated in laboratory.The experimental results show that the agent has little effect on the rheology and filtration loss of polymer drilling fluid and cationic drilling fluid,and can improve the lubricity of drilling fluid.The synthesized polymer film-forming plugging agent LWFD has good plugging properties for sand discs with different permeabilities,and the agent can effectively improve the film-forming plugging and temperature resistance of drilling fluid when combined with the inorganic nano-plugging agent NMFD.The high performance polymer drilling fluid formed by introducing polymer film-forming plugging agent LWFD and inorganic nano-plugging agent NMFD into polymer drilling fluid has comparable performance as Halliburton’s SHALEDRIL high performance drilling fluid,which can meet the requirements of on-site drilling and has application value.
基金This work was supported in part by the National Natural Science Foundation of China(51405418)in part by the Major Program of Natural Science Foundation of Colleges and Universities in Jiangsu Province(18KJA460009)+2 种基金in part by the Jiangsu“Qing Lan Project”Talent Project(2021)Major Projects of Natural Science Research in Jiangsu Higher Education Institutions(Grant No.21KJA460009)General Program of Jiangsu University Natural Science Foundation(22KJD460009).
文摘A method combining computationalfluid dynamics(CFD)and an analytical approach is proposed to develop a prediction model for the variable thickness of the spray-induced liquidfilm along the surface of a cylindrical workpiece.The numerical method relies on an Eulerian-Eulerian technique.Different cylinder diameters and positions and inclinations of the spray gun are considered and useful correlations for the thickness of the liquidfilm and its distribution are determined using various datafitting algorithms.Finally,the reliability of the pro-posed method is verified by means of experimental tests where the robot posture is changed.The provided cor-relation are intended to support the optimization of spray-based coating applications.
文摘Pharmaceutical scientists throughout the world are trying to explore thin films as a novel drug delivery tool. Thin films have been identified as an alternative approach to conventional dosage forms. The thin films are considered to be convenient to swallow, selfadministrable, and fast dissolving dosage form, all of which make it as a versatile platform for drug delivery. This delivery system has been used for both systemic and local action via several routes such as oral, buccal, sublingual, ocular, and transdermal routes. The design of efficient thin films requires a comprehensive knowledge of the pharmacological and pharmaceutical properties of drugs and polymers along with an appropriate selection of manufacturing processes. Therefore, the aim of this review is to provide an overview of the critical factors affecting the formulation of thin films, including the physico-chemical properties of polymers and drugs, anatomical and physiological constraints, as well as the characterization methods and quality specifications to circumvent the difficulties associated with formulation design. It also highlights the recent trends and perspectives to develop thin film products by various companies.
基金the Committee of the National HighTechnology Research and Development Program of China(863 Program) for providing financial support for thisresearch project (Project No.2006AA06A109)the support provided by the Changjiang Scholarsand Innovative Research Team(No.IRT0411),Ministry ofEducation,China.
文摘This paper discusses the systematic design and development of low-damage drilling fluid to protect the low-permeability gas reservoir of the Sulige block in the Ordos Basin, Inner Mongolia Autonomous Region, China. Based on investigation of the geological characteristics and the potential formation damage of the Permian formation of the reservoir, waterblocking due to invasion of drilling or completion fluids was identified one of the most severe causes of damage to gas well deliverability. By adopting the phase trap prevention method, ideal packing theory, and film-forming technology, a lowdamage drilling fluid, sodium formate brine containing efficient waterblocking preventing surfactants, optimized temporary bridging agents (TBAs), and film-forming agents has been developed. The performance of the new drilling fluid was evaluated by using a variety of techniques. The results show that the fluid has good rheological properties, good strong shale-swelling inhibition, good temporary plugging effect, ultra-low filtration, and good lubricity. It can efficiently minimize waterblocking and can be used to drill horizontal wells with minimal intervention of the reservoir in the Sulige Gas Field.
基金financially supported by the National Natural Science Foundation of China (Nos. 51890871, 91833306, and 51573185)the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB12020300)
文摘For poly(9,9-dioctylfluorene)(PFO),β phase (coplanar conformation with the intra-chain torsion angle of 165°) has a greater conjugation length and higher degree of order compared to those of α phase, which favors charge carrier transport. However, the highest content of β phase obtained so far is 45%. We propose to increase the content of β phase by promoting the solution aggregation of PFO molecules and extending film-forming time. For this purpose, 1,8-diiodooctane (DIO) is added to PFO o-xylene solution, which enhances the interaction of PFO chains and improves the planarity of PFO backbone, resulting in the formation of ordered aggregation. The aggregates act as nucleation centers to promote the formation of β phase. The content of β phase increases with increasing DIO concentration and reaches a platform of 39% as DIO is more than 4 vol%. Furthermore, the film is kept in a sealed environment with oxylene atmosphere for 3 h, thus the PFO molecules have enough time to diffuse to the crystallization front and achieve disorder-order transition. As a result, the crystallinity of PFO is improved significantly and the content of β phase increases to 52%, reaching the highest value reported so far.
基金the National Natural Science Foundation of China(grant numbers 51827901,52004166)funded by the Program for Shenzhen Basic Research Program(General Program)(No.JCYJ20190808153416970)Guangdong Introducing Innovative and Enterpreneurial Teams(No.2019ZT08G315)
文摘Accurately obtaining the original information of an in-situ rock via coring is a significant guiding step for exploring and developing deep oil and gas resources.It is difficult for traditional coring technology and equipment to preserve the original information in deep rocks.This study develops a technology for insitu substance-preserved(ISP),moisture-preserved(IMP),and light-preserved(ILP)coring.This technology stores the original information in real time by forming a solid sealing film on the in-situ sample during coring.This study designed the ISP-IMP-ILP-Coring process and tool.In addition,an ISP-IMP-ILPCoring process simulation system was developed.The effects of temperature,pressure,and film thickness on the quality of the in-situ film were investigated by performing in-situ film-forming simulation experiments.A solid sealing film with a thickness of 2-3 mm can be formed;it completely covers the core sample and has uniform thickness.The film maintains good ISP-IMP-ILP properties and can protect the core sample in the in-situ environment steadily.This study verifies the feasibility of“film formation during coring”technology and provides strong support for the engineering application of ISP-IMP-ILPCoring technology.
基金the FINEP/FUNDEP for the awarded grantsthe FAPESP(process#2017/09469-2)for financial support
文摘The present work firstly aimed to obtain cellulose from sugarcane bagasse by using alkaline methods in pulping/delignifying and, at bleaching stages, using sodium chlorite, glacial acetic acid, and hydrogen peroxide, associated to NaOH/KOH. The process was carried out at temperatures varying from 55°C to 110°C, under magnetic stirring in various steps lasting from 2 h to 12 h. The yields of the two cellulose extracted, SCB24-Na-I and SCB24-Na-II, were 37% and 41%, respectively, from samples of ca. 15 g of the bagasse. Secondly, it is to extract nanoparticles from the obtained celluloses via acid hydrolysis (with 77% H2SO4) to lately be tested as reinforcement in biodegradable packagings. Both celluloses and their respective nanoparticles were characterized by several techniques, among them ATR-FTIR, DSC-TGA, XRD, SEM, and TEM. Despite that the yields of cellulose nanoparticles have been low, the preliminary studies of their use in biodegradable films coated on biodegradable pots were promising.
基金the Key Research and Development Project of the Ministry of Science and Technology of China(No.2022YFC3004900)。
文摘Fluorosurfactants are the key ingredients in the formulations of aqueous film-forming foams(AFFFs)for extinguishing flammable liquids,thus developing high-efficient and low-toxic fluorosurfactants is desirable in AFFFs application.Herein,a series of hyperbranched polymeric fluorosu rfactants(HPFs)were successfully synthesized through sequentially modifying hyperbranched polyethylenimine(PEI)with the hydrophilic poly(ethylene glycol)(PEG)chains and the hydrophobic C6/C4-based perfluoroalkyl chains,which were verified by FTIR,^(1)H-and^(19)F-NMR.The surface tensions of all the HPFs in water were measured,and the corresponding physicochemical parameters were interpreted.It was found that the surface activities of HPFs could be tuned through adjusting the ratio of PEG to perfluoroalkyl chains,the length of perfluoroalkyl chains,the molecular weight of PEI core,but not the PEG chain length.In the binary mixture of HPFs with the commercial small molecule fluorosurfactant Capstone^(TM)1157(C1157),a strong synergism led to the elevation of surface activity,which was attributed to the efficient encapsulation of C1157 guests by the compact hyperbranched HPFs as the hosts.The utilization of HPF/C1157 as fluorosurfactant ingredients in AFFF formulations could realize much higher fire-extinguishing efficiency towards flammable oils than the control AFFFs prepa red from the polymeric Capstone^(TM)1460 or the neat C1157.
基金financially supported by the National Natural Science Foundation of China(Nos.21503006 and 91534109)National Key Projects for Fundamental Research and Development of China(No.2017YFB0102200)+1 种基金Beijing Municipal Science and Technology Project(No.D171100005617001)Henan province science and technology cooperation project(No.172106000061)
文摘Three different types of new electrolyte additives were adopted as flame retardant to improve the safety of nickel-cobalt-aluminum(LiNi_(0.8)Co_(0.15)Al_(0.05)O_2, abbreviation NCA) based lithium batteries. By adding 5 wt% of the additives, an obvious flame retardant effect can be observed for the electrolyte. Furthermore,it was found that the additives can help for forming a stable cathode electrolyte interface(CEI) film on the NCA cathode, which are important for enhancing the thermal stability of the electrolyte and make the electrolyte obviously reduce the flammability, as well as good effect on the cycling cycle performance of the battery. These results indicate that our flame retardant are favorable additives in conventional liquid electrolytes for rechargeable lithium-ion batteries with good safety and high performances.