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Microstructure evolution of friction stir processed 2507 duplex stainless steel was investigated at rotational speed of 400 rpm and traverse speed of 100 mm/min. The microstructural evolution in processed zone was studied by optical microscopy and electron backscattered diffraction. Regions in the stir zone and the thermo-mechanically affected zone experienced different microstructure evolution due to different thermo-mechanical processes. The results showed that static recrystallization, dynamic recrystallization, and dynamic recovery occurred in the processed zone. And the ferrite was occurred the recrystallization prior to the austenite.

Carbon quantum dots (CQDs) can be used to modify TiO

The durability of poly(vinyl chloride) (PVC) under long term exposure to heat and ultraviolet ray can be enhanced by adding an additive to improve its thermal stability. In this work, three types of cis-1,2-cyclohexanedicarboxylic acid di-mannitol ester (CAME)-based zinc metal alkoxides with different zinc contents (i.e., CAME-Zn-1, CAME-Zn-2, and CAME-Zn-3 containing 2:1, 1:1, and 1:2 CAME:Zn(O2CCH3)2 molar ratio, respectively) were characterized for the first time as PVC thermal stabilizer additives. Fourier-transform Infrared spectroscopy (FT-IR), elemental analyses results, and thermogravimetric analysis (TGA) results confirmed the formation of Zn-O bonds in CAME-Zn; that the Zn, C, H, and O contents on the as-prepared CAME-Zn are close to the targeted contents; and that CAME-Zn-2 has the highest decomposition temperature. Congo red tests, conductivity tests, and thermal aging tests subsequently revealed that relative to pure PVC, the thermal stability for the stabilized PVC was enhanced by adding thermal stabilizer in the order of ZnSt2/CaSt2 (1:1), CAME-Zn-3, CAME-Zn-1, and CAME-Zn-2. The best thermal stabilizer, i.e., CAME-Zn-2 can resist the color change from white to grey upon heated at 180 °C for up to 60 min. Torque rheological tests showed that CAME-Zn-2 contributes plasticizing effect to PVC. CAME-Zn-2 thus effectively contributes bi-functional roles, i.e., as thermal stabilizer and plasticizer to PVC.

In sharp contrast to the general downward trend around the globe, in China the domestic content in exports has been steadily increasing. The determinants that drive this outstanding result are hotly debated. However, there still lacks a clear causal inference on the determinants of the rising domestic content in China’s exports. This study uses the expansion of higher education that has taken place in China since 1999 as a "quasi-natural experiment" to directly examine its causal effects on the increasing domestic content in Chinese exports. We use the difference-in-difference specification and find that the availability of high-quality human capital has enabled the domestic production of high-quality industrial inputs that substitute for imported intermediates. According to our estimation, the human-capital supply shock can explain roughly one-half of the increase in the domestic content in China's processing exports. This means that domestic reform can be an important driving force for China to capture more domestic value added in its exports, which also serves as an important policy lesson that other developing economies can learn. Through this new perspective, we offer a first look at how behind-the-border policies affect the competitiveness of industries in a globalized world.

In this study, carbon quantum dots (CQDs) were synthesized by a low-cost and scalable approach and the oxygen functional groups were fine-tuned by chemical post-treatment. It was found that the CQDs could be applied as visible-light-responsive photocatalysts for activation of peroxymonosulfate (PMS) and remediation of aqueous organic dyes. Phenylhydrazine modified CQDs (CQDs-PH) presented high efficiency for degradation of methylene blue due to selective removal of carboxylic groups and inhibited recombination of photogenerated electron-hole pairs. The effects of catalyst dosage, species and concentrations of dyes, and initial pH values on the photodegradation efficiency were systematically investigated and the alkaline condition facilitates the separation of photoinduced charge carriers and promotes the dye decoloration. The reactive oxygen species produced in the photocatalysis were identified by radical quenching tests and the mechanism was elucidated. Superoxide radicals were generated from PMS activation via electron transfer from CQDs and played the primary role in organic oxidation. In addition, photogenerated holes on the valence band of CQDs also participated in the dye decomposition.

In this work, a highly sensitive sandwich-type electrochemical immunosensor was fabricated by using the gold nanorods (Au NRs) as the substrate material and the mesoporous Au@Pd@Pt core-shell nanospheres (m-Au@Pd@Pt) as the label of the detection antibodies (Ab2, Ab2 label) for detecting Hepatitis B surface antigen (HBs Ag). The Au NRs with excellent conductivity and biocompatibility can accelerate the electron transfer on the electrode interface and enhance the load capacity of capture antibodies (Ab1). The m-Au@Pd@Pt with mesoporous structure can not only provide high specific surface area and abundant catalytically active sites, but also offer great pore accessibility of guest species from outside. The detection signal of the immunosensor was effectively improved by the novel Ab2 label. With the good cooperation between Au NRs and Ab2 label, a linear relationship between current signal and the logarithm of the HBs Ag concentration was obtained in the wide range of 20 fg/mL to 200 ng/mL and the detection limit of HBs Ag was 6.7 fg/mL (signal-to-noise ratio of 3). Besides, the designed immunosensor shows good reproducibility, long-term stability and high specificity. Crucially, the sensitive and selective response to HBs Ag in real human serum samples confirms that the designed immunosensor will be promising in the clinical diagnosis of biomarkers.

The transition behavior of coarse AlN during cold rolling in the low-temperature grain-oriented silicon steel normalized sheet was investigated using field emission scanning electron microscopy (SEM) and field emission transmission electron microscopy (TEM). The SEM observation results showed that the size of AlN decreased with the increase of the cold rolling reduction rate, and the average sizes of AlN in the normalized specimen and the cold-rolled specimens with the cold rolling reduction rates of 14%, 23%, 30%, 40%, and 89% were approximately 1734, 771, 742, 582, 490, and 96 nm, respectively. The morphology of AlN nearly transformed from rectangle to irregular polygon when the cold rolling reduction rate exceeded 23%. Meanwhile, the mechanism of the refinement of AlN during cold rolling was characterized by TEM. The high-resolution transmission electron microscopy (HRTEM) analysis results confirmed that the refinement of coarse AlN during cold rolling was caused by the shear effect of dislocation slip because lots of slip traces, which were produced by dislocation slip along some slip systems of AlN, such as (01 1 ‾ 0)[2 1 ‾ 1 ‾ 0], (0 1 ‾ 11)[2 1 ‾ 1 ‾ 0], and (0001)[2 1 ‾ 1 ‾ 0] slip systems, were observed in AlN. Moreover, it was also found that after a coarse AlN was sheared to become two parts, the orientations of them would be slightly different when the slip plane of AlN was not completely parallel to that of the matrix before shearing. Therefore, based on these results, it was confirmed for the first time that the coarse AlN precipitated in low-temperature grain-oriented silicon steel normalized sheet was shearable and could be refined after cold rolling. The possible mechanisms were summarized as follows: the orientation relationship between AlN and matrix might be randomly changed during cold rolling owing to the considerable stress concentration around AlN, making it possible that the slip plane of AlN matched with that of the matrix, at this time, the dislocations slipping in the matrix could glide into and shear AlN with the slip system of matrix changing into the slip system of AlN.

A novel pentaerythritol stearate ester-based zinc alkoxide (PSE-Zn) was synthesized through a two-step method. Zinc ethoxide was first prepared from zinc acetate and ethanol, and then with ethanol as the solvent, the obtained zinc ethoxide ester was heated together with pentaerythritol stearate to produce PSE-Zn. PSE-Zn could be used as a promising poly(vinyl chloride) (PVC) thermal stabilizer. Conductivity tests, thermal aging tests, and UV-visible spectroscopy were used to study the thermal stabilization performance of the thermal stabilizers of PSE-Zn on PVC. The results showed that, with a lower melting point and a good compatibility with PVC, PSE-Zn presented a significant improvement in maintaining the initial color of PVC. However, the color of PVC stabilized with pure PSE-Zn began to degrade when the sample was heated at 180°C for 60 min indicating the unsatisfactory long-term thermal stability presented by PSE-Zn on PVC. So, some commercial thermal stabilizers, for example, calcium stearate (CaSt2), zinc stearate (ZnSt2), or CaSt2/ZnSt2 were employed along with PSE-Zn to further improve the stabilizing performance. The results showed that there was a synergistic effect that was between 2 phr PSE-Zn and 2 phr CaSt2 and made the stabilized PVC possess the best thermal stability. Because of the presence of free hydroxyl in PSE-Zn, which could chelate ZnCl2, PSE-Zn can then restrain “zinc-burning” phenomenon when PSE-Zn and ZnSt2 were used together. It was also found that PVC stabilized with 3 phr PSE-Zn and 1 phr CaSt2/ZnSt2 had the best color stability. The mechanism of thermal stability of PSE-Zn was also discussed. As a metal alkoxide, PSE-Zn is readily to neutralize HCl. In addition, PSE-Zn is able to replace the allyl chloride to terminate the dehydrochlorination of PVC. Moreover, because of the stearate radicals, PSE-Zn had a very low melting point, a better compatibility with PVC, and a lubrication action. With these excellent properties, PSE-Zn would be able to make PVC achieve an excellent initial color and a long-term stability. J. VINYL ADDIT. TECHNOL., 2017. © 2017 Society of Plastics Engineers

An egg shell-yolk NiO/C porous composite has been prepared as lithium-ion battery anode material by two-pot hydrothermal method. Thermogravimetry(TG), X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), Raman spectroscopy, and nitrogen isothermal adsorption-desorption have been used to study the microstructure of the material. LANHE cell tester and electrochemical workstations are used to investigate electrochemical performance. Results show that amorphous carbons exist in porous NiO/C, which possesses an internal loose spherical structure. The discharge capacity for the 100th cycle is maintained at 625.3mAh/g, and the capacity retention ratio is 94.1% relative to the 2nd discharge capacity. The composite has a unique egg shell-yolk porous structure, which buffers the volume change and prevents the aggregation of active NiO material during cycling to enhance material performance. When the current density is increased to 800 mA/g, the capacity stabilizes at 400.1mAh/g, reflecting an outstanding rate performance.

A green and facile protocol of thermal treatment of graphene oxide (GO) with urea was adopted to synthesize nitrogen-doped graphene (NG-Urea-air) at a low temperature (350 °C) in the static air. The resulting sample exhibited outstanding catalytic performance to activate peroxymonosulfate (PMS) toward organic degradation. The NG-Urea-air induced 49.7- and 11.5-fold enhancement over GO and pristine reduced graphene oxide (rGO-air). Moreover, the influences of nitrogen precursors including organic chemicals (urea, cyanamide, and melamine) and inorganic salts (ammonium nitrate and ammonium chloride) were investigated, and urea was demonstrated to be the best precursor for synthesizing N-doped graphene with a relative high doping level (18.7 at.%). The classical radical quenching and advanced in situ electron paramagnetic resonance (EPR) technology revealed that the outstanding oxidative effectiveness of PMS/NG-Urea-air system was originated from the nonradical oxidation pathway, in which PMS was activated by the positively charged carbon domains next to nitrogen atoms and the phenol was oxidized simultaneously on the carbon network via rapid charge transfer. Meanwhile, singlet oxygen and radicals may also partially contribute to the complete phenol degradation. This study facilitates a fundamental investigation of heteroatom doping progress during thermal treatment and sheds light on the insights into carbocatalysis in environmental remediation.

A novel shape controlled Cu2O/reduced graphene oxide/In2O3 (Cu2O/RGO/In2O3) hybrid with abundant oxygen vacancies was prepared by a facile, surfactant-free method. The hybrid photocatalyst exhibits an increased photocatalytic activity in water oxidation and degradation of environmental pollutants (methylene blue and Cr6+ solutions) compared with pure In2O3 and Cu2O materials. The presence of oxygen vacancies in Cu2O/RGO/In2O3 and the formation of heterojunction between In2O3 and Cu2O induce extra diffusive electronic states above the valence band (VB) edge and reduce the band gap of the hybrid consequently. Besides, the increased activity of Cu2O/RGO/In2O3 hybrid is also attributed to the alignment of band edge, a process that is assisted by different Fermi levels between In2O3 and Cu2O, as well as the charge transfer and distribution onto the graphene sheets, which causes the downshift of VB of In2O3 and the significant increase in its oxidation potential. Additionally, a built-in electric field is gener...

CoO/Co 3 O 4 /graphene nanocomposites were successfully synthesized through an easy, accessible method followed by annealing treatment. Graphene was used as the appropriate carrier to load CoO/Co 3 O 4 nanoparticles because of its high surface area. The CoO/Co 3 O 4 /graphene nanocomposites were then tested as anode material for lithium-ion batteries (LIBs). Results showed that the nanocomposites led to high capacity, delivering initial discharge–charge capacities of 1093.4 and 825.3 mAh·g −1 , with an initial coulombic efficiency of 75.5%. The nanocomposite electrode showed excellent rate capability and impressive cyclability, as well as a high reversible capacity of 695.4 mAh·g −1 after 70 cycles at a discharge–charge current density of 0.5 C (1 C = 890 mA g −1 ). The excellent electrochemical performance was ascribed to the CoO nanoparticles and graphene. By contrast, pristine Co 3 O 4 can maintain only 339.7 mAh·g −1 after 70 cycles, indicating very poor cycling performance because of the huge volume change during cycling. These results revealed that the nanocomposites were excellent anode material for LIBs.

NiO–SnO2/GNs ternary composites were synthesized by hydrothermal approach and subsequent calcination in nitrogen atmosphere. Structural characteristics of the composites were investigated by a series of physical measurements, such as X-ray diffraction measurement, scanning electron microscopy, and transmission electron microscopy. Results showed that NiO-SnO2 particles were distributed on graphene and had formed a well-ordered, sheet-like structure. The content of NiO was relatively small and distributed along the carbon substrate, which can improve the decomposition process of irreversible Li2O. Electrochemical performance measurements demonstrated that the discharge capacity of NiO–SnO2/GNs, unlike NiO-SnO2 materials, increased from 1022.2 mAh/g to 1212.9 mAh/g and maintained at 649.3 mAh/g after 50 cycles. The contribution of capacity during discharge progress can be explained by three parts: the reaction between SnO2 and Li, the reaction between NiO and Li, and the alloying process between Sn and Li. In addition to the catalytic characteristic from nickel-based oxides, the unique structure of graphene can buffer the volume change and prevent the aggregation of the active materials upon cycling to enhance the material performance. Furthermore, the high conductivity of graphene decreased the material internal resistance.

A new di-mannitol adipate ester-based zinc metal alkoxide (DMAE-Zn) was synthesized as a bi-functional poly(vinyl chloride) (PVC) thermal stabilizer for the first time. The materials were characterized with Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). Characterization results confirmed the formation of Zn&ndash, O bonds in DMAE-Zn, and confirmed that DMAE-Zn had a high decomposition temperature and a low melting point. The thermal stability of DMAE-Zn on PVC also was tested by a conductivity test, a thermal aging test, and a UV-visible spectroscopy (UV-VIS) test. PVC stabilized by DMAE-Zn had a good initial color and excellent long-term stability. UV-VIS also showed that the conjugated structure in PVC stabilized by DMAE-Zn was almost all of the triene, suggesting that the addition of DMAE-Zn would suppress the formation of conjugated structures above tetraene. The dynamic processing performance of PVC samples tested by torque rheometer indicated that, having a good compatibility with PVC chains in the amorphous regions, DMAE-Zn contributed a good plasticizing effect to PVC. DMAE-Zn thus effectively demonstrates bi-functional roles, e.g., thermal stabilizers and plasticizers to PVC. Furthermore, FT-IR, a HCl absorption capacity test, and a complex ZnCl2 test were also used to verify the thermal stability mechanism of DMAE-Zn for PVC.

Thermal stabilizers, lubricant, and plasticizers are three crucial additives for processing poly(vinyl chloride) (PVC). In this study, a new mannitol stearate ester-based aluminum alkoxide (MSE-Al) was designed and synthesized as a novel additive for PVC. The thermal stability and processing performance of PVC stabilized by MSE-Al were evaluated by the Congo red test, conductivity measurement, thermal aging test, ultravioletevisible (UV&ndash, Vis) spectroscopy test, and torque rheometer test. Results showed that the addition of MSE-Al could not only markedly improve the long-term thermal stability of PVC, but also greatly accelerate the plasticizing and decrease the balance torque, which demonstrated that MSE-Al possessed a lubricating property. Thus, MSE-Al was demonstrated to be able to provide tri-functional additive roles, e.g., thermal stabilizer, plasticizer, and lubricant. The test results for the thermal stability of PVC indicated that the initial whiteness of PVC stabilized by MSE-Al was not good enough, thus the synergistic effect of MSE-Al with zinc stearates (ZnSt2) on the thermal stability of PVC was also investigated. The results showed that there is an appreciable synergistic effect between MSE-Al and ZnSt2. The thermal stabilization mechanism and synergism effect of MSE-Al with ZnSt2 are then discussed.

A new di-mannitol adipate ester-based zinc metal alkoxide (DMAE-Zn) was synthesized as a bi-functional PVC thermal stabilizer for the first time. The materials were characterized with Fourier-transform Infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). Characterization results confirmed the formation of Zn-O bonds in DMAE-Zn; and that DMAE-Zn had a high decomposition temperature and a low melting point. The thermal stability of DMAE-Zn on PVC also was tested by conductivity test, thermal aging test, and UV-visible spectroscopy (UV-VIS) test. PVC stabilized by DMAE-Zn had a good initial color and excellent long-term stability. UV-VIS also showed that the conjugated structure in PVC stabilized by DMAE-Zn was almost all of the triene, suggesting that the addition of DMAE-Zn would suppress the formation of conjugated structures above tetraene. Dynamic processing performance of PVC samples tested by torque rheometer indicated that, having a good compatibility with PVC chains in the amorphous regions, DMAE-Zn contributed good plasticizing effect to PVC. DMAE-Zn thus effectively demonstrates bi-functional roles, e.g., thermal stabilizers and plasticizers to PVC. Furthermore, FT-IR, HCl absorption capacity test, and complex ZnCl2 test were also used to verify the thermal stability mechanism of DMAE-Zn for PVC.

There is a wide demand for PVC products with microbiocidal property. For this purpose, additional antimicrobial agents have to be added. In this work, we synthesized pentaerythritol p-hydroxybenzoate ester-based zinc metal alkoxides (PHE-Zn) additive as highly efficient antibacterial agent, thermal stabilizer, plasticizer and lubricant for PVC. PHE-Zn was characterized by Fourier-transform infrared spectrometer (FT-IR), X-ray photoelectron spectroscopy (XPS), and elemental analysis. The results confirm the formation of R-O-Zn bonds and the molecular structure of PHE-Zn. The property enhancement of PVC by PHE-Zn were investigated by conductivity, oven aging, and torque rheological tests. PHE-Zn not only contributes to excellent initial whiteness and significant long-term thermal stability (without color change up to 90 min), but also improves plasticization and lubrication of PVC. In addition, using E. coli (E. coli) and Staphylococcus aureus (S. aureus) as typical microorganisms, the antibacterial properties of PHE-Zn stabilized PVC were tested. PVC with 4 phr PHE-Zn displayed high killing rates against E. coli and S. aureus (97.92% and 91.84%, respectively). Further experiments showed that PHE-Zn was a contact-active antibacterial agent. Moreover, the mechanisms for the enhanced thermal stability and biocidal property of PHE-Zn on PVC was explored.

Metal-free semiconductors offer a new opportunity for environmental photocatalysis toward a potential breakthrough in high photo efficiency with complete prevention of metal leaching. In this study, graphitic carbon nitride (GCN) modified by oxygen functional groups was synthesized by a hydrothermal treatment of pristine GCN at different temperatures with H2O2. Insights into the emerging characteristics of the modified GCN in photocatalysis were obtained by determining the optical properties, band structure, electrochemical activity and pollutant degradation efficiency. It was found that the introduction of GCN with oxygen functional groups can enhance light absorption and accelerate electron transfer so as to improve the photocatalytic reaction efficiency. The photoinduced reactive radicals and the associated photodegradation were investigated by in situ electron paramagnetic resonance (EPR). The reactive radicals, O2(-) and OH, were responsible for organic degradation.

In this work, a non-volatile solid organotin thermal stabilizer, pentaerythritol stearate ester-based tin (II) metal alkoxides (PSE-Sn) was synthesized with a very simple process and its impact on the thermal stability and processing performance of PVC was evaluated by conductivity measurement, thermal aging, thermogravimetric analysis, and torque rheometer test. The results showed that the addition of PSE-Sn not only could significantly enhance the thermal stability of PVC, accelerate plasticization, but also improve lubrication performance during PVC processing. Thus, PSE-Sn played the role of tri-functional additives: thermal stabilizer, plasticizer, and lubricant. The joint effects of PSE-Sn with ZnSt2 and CaSt2 on the thermal stability of PVC were also evaluated. Results indicate that there is a good synergistic effect between PSE-Sn and ZnSt2 on the initial color and long-term thermal stability of PVC. However, such synergistic effect was not observed between PSE-Sn and CaSt2. In addition, the working mechanism of PVC stabilization by PSE-Sn was also explored. Furthermore, the thermal stability and processing performance of PSE-Sn and methyl tin mercaptide (MTM) on PVC were comparatively tested. PVC stabilized by MTM possessed the longest color stability. The addition of PSE-Sn could also improve the initial color stability and long-term thermal stability of PVC significantly. The results of tensile test showed that both PSE-Sn and MTM could reduce the average tensile strength of PVC but increase the average elongation at break of PVC.

Lanthanum-pentaerythritol (La-PE) alkoxide, a polyol-based metal alkoxide, had been synthesized and used as a thermal stabilizer for polyvinylchloride (PVC). Thermogravimetric (TG), differential thermal analysis (DTG), mass spectrum (MS), and Fourier transform infrared (FTIR) spectroscopy were used to confirm the synthesis reaction. The thermal stability of rigid PVC stabilized with La-PE was tested by means of the Congo Red test, conductivity test, thermal aging test, thermal gravimetric analysis (TGA), and UV-visible (UV-vis) spectroscopy. The results showed that addition of La-PE could significantly prolong static stability time of PVC and increase the apparent activation energy for degradation reaction. The oven aging test showed that La-PE could improve the initial color of PVC. Moreover, addition of La-PE could significantly reduce the concentrations of the conjugated double bonds of PVC and reduce weight loss. The possible thermal stability mechanism had also been discussed. Besides having good ability to neutralize hydrochloric acid (HCl), La-PE could substitute or inactivate the labile chlorine atoms in the PVC chains. J. VINYL ADDIT. TECHNOL., 2015. © 2015 Society of Plastics Engineers

The mechanism of strengthening the leaching of vanadium from petroleum coke by surfactant was investigated. When the surfactant was used, the leaching efficiency was improved, the leaching amount of vanadium increased from 390 to 540 ppm at 303 K. The surface physical chemical properties of the leaching solution, such as the conductivity, the surface tension, contact angle, and zeta potential were studied before and after the surfactant is added. The zeta potential increased from –20 to 40 mV, when the surfactant was used from 0 to 700 mg/L, and the surface tension and contact angle decreased significantly first, then remained constant; the interface energy increased. All the change of physical chemical properties enhanced wetting capability and combination adhesion. And this improved the leaching efficiency.

Lanthanum-pentaerythritol alkoxide (La-PE) was obtained by the traditional preparation method which was a reaction between La 2 O 3 and pentaerythritol. The synergistic effects of La-PE with zinc stearates (ZnSt 2 ) and with stearoyl benzoyl methane (β-diketone) on the thermal stability of poly(vinyl chloride) (PVC) were evaluated by the conductivity test, thermal aging test, and Ultraviolet–visible (UV-VIS) spectroscopy test. The results showed an improvement on the color stability and the long-term thermal stability of PVC, indicating that there was an obvious synergistic effect between La-PE and ZnSt 2 . In order to explore the mechanism, the capacity of La-PE to react with HCl was tested. The results showed that La-PE had lower capacity to neutralize HCl (80.30 mg HCl/1 g) than ZnSt 2 (92.71 mg HCl/1 g). Furthermore, the thermal stability test of PVC stabilized with La-PE/ZnCl 2 showed that the thermal stability of PVC with La-PE/ZnCl 2 was similar to that of PVC with La-PE/ZnSt 2 but better than PVC with pure La-PE. Thus, a possible synergistic mechanism of La-PE and ZnSt 2 could be described where zinc species could catalyze the reaction of La-PE and the labile chlorine atoms in PVC chains. Moreover, the hydroxyl group on La-PE could chelate ZnCl 2 to inhibit the “zinc burning” phenomenon. However, there was no synergistic effect observed between La-PE and β-diketone. Discoloration in PVC samples that stabilized with La-PE and β-diketone was noticed as early as in the milling process by the open twin-roller at 180 °C, even though it took 110 min for the reaction to change the color to completely black. The results of UV-VIS spectroscopy showed that a strong peak appeared at 360 nm representing the enol form of β-diketone when the dosage of β-diketone exceeded 1 phr. This indicated that the enol form of β-diketone did the work in the thermal stabilizing process and the dosage of β-diketone needed in the PVC stabilizers was very low.

A novel shape controlled Cu

Pentaerythritol-aluminum (PE-Al) was synthesized by a solid-phase reaction in this study. The formation and characteristics of PE-Al were confirmed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). SEM images showed that the shapes of PE-Al particles were spherical and the average size was around 23 nm. The thermal properties of rigid poly(vinyl chloride) (PVC) with PE-Al were tested by Congo red test, thermal aging test, conductivity test, thermogravimetric analysis (TGA), and UV–visible spectroscopy test. The results showed that combination of PE-Al, in comparison with commercial thermal stabilizers, presented an obvious improvement in stabilization efficiency of PVC. Moreover, addition of PE-Al could significantly prolong static stability time of PVC, reduce weight loss, and improve the initial color of PVC films. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3704–3709, 2013

Pentaerythritol-zinc (called Penzinc), which is a novel thermal stabilizer for PVC, was synthesized, and its performance was characterized during the thermal processing of PVC. The stabilization effects of this new stabilizer combined with calcium stearate (CaSt2) and stearoyl benzoyl methane (β-diketone) were investigated using conductivity tests, thermal aging tests, and torque rheometry tests. The results revealed that the addition of Penzinc can improve the color and thermal stability of PVC in both static and dynamic tests. There are no obvious synergistic effects between Penzinc and CaSt2. However, the synergistic action between Penzinc and β-diketone is excellent. The thermal stability mechanisms of Penzinc and β-diketone are also discussed with the help of quantum chemical calculations. Pentaerythritol-zinc (Penzinc) has been synthesized and its thermal stability, especially its synergism with β-diketone and calcium stearate, was characterized. Experimental results show that PVC stabilized with complex of Penzinc and β-diketone has an excellent initial color and long-term thermal stability. Moreover, the thermal stability mechanism of Penzinc and β-diketone are also discussed with the help of quantum chemical calculations. Results indicate that both α-H atom of β-diketone and zinc atom of Penzinc, having low electron density, can easily react with labile chloride atom of PVC, which has high electron density.

The diesel engine power demand of the start condition can be separated into two parts including resistance overcoming and acceleration realization for the reason that there is no power output during the starting process. The present paper mainly focuses on the fuel injection quantity control based on the engine power demand especially the acceleration demand for the resistance force is fixed for a specific engine, and the starting acceleration velocity is set as a target curve so that the acceleration process can also be fixed. The feasibility of the start control strategy proposed in this paper was verified by a comparison of the traditional starting control with a constant fuel quantity, and starting performance of the target acceleration based control shows predominance to the constant quantity control. And then the comparison between various starting acceleration processes, which was realized by the settings of acceleration curve slope factor, was conducted and results showed that the acceleration processes with higher slope factors perform better.