Measurement of water by oven evaporation using a novel oven design. 2. Water in motor oils and motor oil additives

The measurement of water in lubricating oils is important because water accelerates the corrosion of metal parts and bearings in motors. Some of the additives added to lubricating oils to improve their performance react with the Karl Fischer reagent (KFR) causing a positive bias in the water measurement. A new oven evaporation technique for measuring water in oils has been developed that is automated, requires less sample handling, is easily calibrated, and is capable of measuring relatively small mass fractions of water (50 mg/kg sample). A series of motor oils was analyzed with the standard KFR, a reagent that detects interfering substances that reduce iodine, and the aldehyde–ketone reagent that does not detect substances that react with methanol and form water. The oil samples were heated to 107°C and then reheated to 160°C. At both temperatures, material was measured by both KFRs, but only zinc dithiophosphate released sulfur compounds that would react with the reagent that detects interfering substances. Mass fractions of between 20 and 70% of the volatile material released at either temperature were measured with the standard KFR but not with the aldehyde–ketone reagent. These results demonstrate that there are a number of sources of positive bias in the measurement of water in motor oils and that the standard KFR cannot be used to measure water in motor oils and motor oil additives. These results also indicate that some of the material reacts with methanol to form water. Finally, these results suggest that some of the material that is volatile at 160°C and not at 107°C may be water that is physically occluded or may be substances that react with diethyleneglycol monomethylether to produce water.     

五彩湾煤灰的烧结特性及不同添加剂的影响规律

采用热机械分析仪、高温热台显微镜、XRD及FactSage软件相结合的方法,研究了五彩湾煤灰的烧结特性及不同添加剂的影响规律。结果表明,沙子(SiO_2含量约为80%)和煤矸石(SiO_2含量为54%,Al_2O_3含量为42%)能改变煤灰的烧结特性(烧结温度和烧结速率),但不同添加剂改变的程度不同。添加10%的沙子能使烧结温度提高70℃,而0-15%煤矸石不能使烧结温度升高。此外,烧结速率随添加剂增多而减小,烧结区间随添加剂增多而延长。进一步研究表明,添加剂能够改变煤灰初始液相温度、组成、含量、煤灰中硫酸盐的分解温度及初始液相温度从而改变煤灰的烧结特性。     

添加剂对基于PBDTC_(10)DBT∶PC_(61)BM光伏器件性能的影响

制备ITO/PEDOT∶PSS/PBDTC10BDT∶PC61BM/LiF/Al聚合物薄膜,研究了添加剂OT,DBrO对光敏层PBDTC10DBT∶PC61BM的影响,结果表明,加入微量的添加剂对光活化层的光吸收以及形貌起到积极的作用,添加剂的加入使得光活化层的分子排列更加有序,使各组分能够更好的吸收太阳光,同时光活化层的粗糙度减小,各组分之间的分布更加均匀,OT,DBrO的最佳添加量分别为2.5%和3%。当OT添加量为2.5%时,器件有最高光电转换效率1.93%。研究结果将为微相调节方法提高光伏器件性能提供理论依据和技术支持。     

Strategies for controlling the active layer morphologies in OPVs

This review focuses on the recent developments in our understanding of active layer morphologies for organic photovoltaic cells and approaches to obtain active layer morphologies for high power conversion efficiencies. The evolution of active layer morphologies, as studied by high resolution electron microscopy, X-ray and neutron scattering, and dynamic secondary ion mass spectrometry, is covered, along with strategies including the use of small molecule additives, polymer nanowires and polymer nanoparticles to realize active layer morphologies. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012     

Effect of the Metal Phenylphosphonates on the Nonisothermal Crystallization and Performance of Isotactic Polypropylene

The use of metal phenylphosphonates as efficient nucleating agents (NAs) for isotactic polypropylene (iPP) is reported and a possible structural correlation to the nucleation efficiency is studied. First, three kinds of metal phenylphosphonates are synthesized via reflux method: Ca(C₆H₅PO₃)?2H₂O (CaPPA), Ca(C₆H₅PO₃H)₂ (CaPPA2), and Al(HO₃PC₆H₅)(O₃PC₆H₅)?H₂O (AlPPA2). Then, the nonisothermal crystallization behaviors, mechanical, and optical properties of iPP composites are investigated. Compared to CaPPA2 and AlPPA2, CaPPA exhibits more effective heterogeneous nucleation effect during iPP crystallization. Furthermore, the nucleation efficiency of CaPPA is similar to industrial standard NAs NA‐21 and NA‐11. With the addition of 0.1 wt % CaPPA, the crystallization temperature is enhanced and the parameter F(T) of Mo method is decreased appreciably. Moreover, the flexural modulus, impact strength, and haze values of iPP composites are improved remarkably by introducing CaPPA. The CH/π interaction between polymer and aromatic cleft of CaPPA is considered to facilitate the attachment of iPP chains and subsequent nucleation and crystallization, which is verified by the viscoelastic properties of pure iPP and composites. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 161–173     

Functional micropatterned surfaces prepared by simultaneous UV‐lithography and surface segregation of fluorinated copolymers

A new procedure focused on the design and preparation of structured and functional polymer surfaces by combination of two approaches acting simultaneously is developed. The elaboration of micrometer size patterned surfaces by UV‐light lithography is reported where, in addition, the surface chemical composition can be controlled by surface segregation of a fluorinated copolymer incorporated in the photopolymerizable mixture. As evidenced by contact angle and XPS measurements, the surface composition can be modified depending on such factors as with the environmental conditions or the concentration of copolymer in the blend. Moreover, the functionality of the copolymer is enhanced by the surface pattern created. As a consequence, the wettability of the films can be modified depending on the pattern and composition of the blend. By using this methodology, functional adaptive sensitive surfaces with a well‐defined topography will be obtained in one single step and without the use of tedious and time‐consuming multistep procedures. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Enhanced electrochemical properties of a novel polyvinyl formal membrane supporting gel polymer electrolyte by Al2O3 modification

Polyvinyl formal (PVFM)‐based dense polymer membranes with nano‐Al₂O₃ doping are prepared via phase inversion method. The membranes and also their performances as gel polymer electrolytes (GPEs) for lithium ion battery are studied by field emission scanning electron microscope, X‐ray diffraction, differential scanning calorimetry, mechanical strength test, electrolyte uptake test, electrochemical impedance spectroscopy, cyclic voltammetry, and charge–discharge test. The polymer membrane with 3 wt % nano‐Al₂O₃ doping shows the improved mechanical strength of 12.16 MPa and electrolyte uptake of 431.25% compared with 10.47 MPa and 310.59% of the undoped sample, respectively. The membrane absorbs and swells liquid electrolyte to form stable GPE with ionic conductivity of 4.92 × 10^?4 S cm^?1 at room temperature, which is higher than 1.77 × 10^?4 S cm^?1 of GPE from the undoped membrane. Moreover, the Al₂O₃‐modified membrane supporting GPE exhibits wide electrochemical stability window of 1.2–4.8 V (vs. Li/Li⁺) and good compatibility with LiFePO₄ electrode, which implies Al₂O₃‐modified PVFM‐based GPE to be a promising candidate for lithium ion batteries. © 2014 Wiley Periodicals, Inc. J. Polym. Sci. Part B: Polym. Phys. 2014 , 52, 572–577     

Chiral Morphology of Calcium Carbonate Mineralized in Agarose Gel

Calcareous crystallites with chiral morphology are difficult to obtain in vitro . Using the d ‐form of aspartic acid as crystal modifier, calcium carbonate with chiral morphology has been obtained in agarose gel. We show that the formation of the chiral morphology of crystallites does not necessarily involve complicated cellular processes.     

Novel Sensors for Batch and Flow Injection Analysis of Histamine Based on Crown Ethers

Six types of histamine potentiometric sensors are developed. They are based on using dibenzo‐30‐crown‐10 (DB30C10) with potassium tetrakis(p‐chlorophenyl)borate lipophilic additive (Type I), dibenzo‐30‐crown‐10 without additive (Type II), dibenzo‐24‐crown‐8 (DB24C8) with the same additive (Type III), dibenzo‐24‐crown‐8 without additive (Type IV), dibenzo‐18‐crown‐6 with the additive (Type V) and dibenzo‐18‐crown‐6 without additive (Type VI) as neutral carriers for histamine. Sensors based on dibenzo‐30‐crown‐10 with (PTp‐C1PB) lipophilic additive (Type I) and dibenzo‐30‐crown‐10 without additive (Type II) show good response. The other sensors Types III–VI show poor response in terms of calibration range and slope.     

Microwave assisted solid additive effects in simple dry chlorination reactions with n-chlorosuccinimide

Solid additives participate in the dry microwave assisted chlorination reaction of N-chlorosuccinimide with the xylenes affecting both yields and chemoselectivities. Total yields can be increased up to nine times for simple alkylaromatics and chemoselectivities can be altered according to the desired ring or α-side chlorination product by choosing the appropriate additive. We believe that in these reactions the solid additives play a very important role by increasing yields and affecting chemoselectivities, as well as behaving as microwave energy absorbers that consequently aid the transfer of heat to the active reagents.