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The development of highly stable and efficient oxide-based red phosphors is urgently required for next-generation lighting devices. Herein, we report the micro/crystal structures and luminescent properties of single-phase Eu2(WO4)3 and Eu3+-doped WO3-Eu2(WO4)3 composite phosphors prepared by a one-step conventional solid-state reaction method in air atmosphere. As increasing Eu contents in the mixtures of WO3 and Eu2O3, the intensities of the X-ray diffraction peaks of Eu2(WO4)3 increased while that of WO3 decreased. The photoluminescence intensity of the synthesized phosphors increased with increase in the Eu content when calcined at 900 °C, while it degraded at a higher temperature. Red-emitting single-phase Eu2(WO4)3 powders were successfully obtained when the WO3 and Eu2O3 powders were calcined in the ratio of 3:1. The intensity of the red emission spectra of the Eu2(WO4)3 phosphor was higher than those of the 6, 12, and 24 at.% Eu-added WO3 composites at excitation wavelengths of 394 and 465 nm. On the other hand, the intensity of emission from the single-phase phosphor was lower than that of the Eu-doped WO3-Eu2(WO4)3 composites under excitation of UV light at 254 nm. Thus, we propose two prospective phosphors for application as red phosphors at various wavelengths.

We developed highly efficient quantum dot light-emitting devices (QD-LEDs) by improving the charge balance with triple hole injection and transport layers consisted of MoO3/poly[N,N′-bis(4-butylphe...

Thermally cross-linkable host materials, DV-TPACZ, DV-TPADBCZ, and TV-TPBI, were designed and synthesized for solution-processed organic light-emitting diodes (OLEDs). The synthesized styrene-functionalized host materials were thermally cross-linked by curing at 150-200 °C without using a polymerization initiator. Excellent solvent resistance was observed for all cured host films. They exhibited low highest occupied molecular orbital energy levels of 5.4-5.7 eV, which indicated a low hole injection barrier from the hole transport layer to the emissive layer. A solution-processed red phosphorescent OLED with 5 wt% (MPHMQ)₂Ir (tmd) dopant in the thermally cross-linkable DV-TPACZ host exhibited a current efficiency of 5.3 cd/A, power efficiency of 3.2 lm/W, and external quantum efficiency of 3.6%.

Microreactors are emerging as an efficient, sustainable synthetic tool compared to conventional batch reactors. Here, we present a new numbering-up metal microreactor by integrating a flow distributor and a copper catalytic module for high productivity of a commercial synthetic drug. A flow distributor and an embedded baffle disc were manufactured by CNC machining and 3D printing of stainless steel (S/S), respectively, whereas a catalytic reaction module was composed of 25 copper coiled capillaries configured in parallel. Eventually, the numbering-up microreactor system assembled with functional modules showed uniform flow distribution and high mixing efficiency regardless of clogging, and achieved high-throughput synthesis of the drug "rufinamide", an anticonvulsant medicine, via a Cu(i)-catalyzed azide-alkyne cycloaddition reaction under optimized conditions.

Correction for ‘A cross-linkable hole transport material having improved mobility through a semi-interpenetrating polymer network approach for solution-processed green PHOLEDs’ by So-Ra Park et al., J. Mater. Chem. C, 2018, 6, 7750–7758, DOI: 10.1039/C8TC01435C.

We report an influence of abnormal mixing effect of host systems having undesirable energy level and transport level in the emission layer (EML). Rather, we focused on their device performance and stability (e.g. driving lifetime) when it was prepared by solution-process. The resultant green phosphorescent organic light emitting diodes (s-OLEDs) showed reasonable device performance and interesting photo-physical properties, which revealed that we can achieve good performance if an appropriate compromise between the factors which govern a charge transport and an energy transfer processes can be realized albeit the EML has undesirable host systems with both bad energy level matching (e.g., HOMO, LUMO levels) and charge transport properties. In this study, a high performance of the s-OLEDs by controlling photo-physical pathways such as exciton quenching process (e.g. triplet-triplet annihilation). Besides, such kind of change in photo-physical pathway may be optimized by controlling the charge balance (i.e. carrier transport behaviour) where we intentionally selected N- and P-type host materials (denote NH and PH, respectively) with abnormal HOMO and LUMO energy levels.

Background : This study evaluated functional outcomes using newly established clinical pathways after hip fracture surgery in older adults and analyzed the major determinants of successful functional outcomes in rehabilitation programs using standardized clinical pathways. Methods : This was a retrospective cohort study performed in a tertiary rehabilitation facility. A total of 220 patients who had received unilateral hip fracture surgery were followed up from immediately after surgery to 6 months postoperatively. Clinical pathways for rehabilitation included early, individualized rehabilitation, education for activities of daily living, review of general medical conditions, and arrangement of discharge settings. One rehabilitation specialist consecutively checked ambulatory function using 3-level grading, and patients were classified into good recovery and poor recovery groups based on ambulatory function at 6 months postoperatively. Logistic regression analysis was performed using 7 representative variables (age, sex, bone mineral density, Mini-Mental Status Examination [MMSE], Berg Balance Scale [BBS], premorbid ambulatory function, and length of hospital stay). Results : A total of 86.8% of patients could walk with or without assistance at 6 months after surgery and 75.5% of patients involved in the rehabilitation program were classified into the good recovery group in this study. The good recovery group showed higher MMSE and BBS scores compared with the poor recovery group. The factors in the model most strongly correlated with recovery were MMSE and BBS. Conclusion : This study showed that a well-designed rehabilitation program could improve ambulatory function in older patients after hip fracture surgery and that cognitive impairment and poor balance control may inhibit the recovery of ambulatory function.

A novel cross-linkable hole transport material (HTM) was used to form a robust layer structure upon continuous wet processes such as spin coating or ink-jet printing. The significantly reduced hole mobility of the cross-linked HTM (x-HTM) was dramatically improved by a semi-interpenetrating polymer network (semi-IPN) approach for ideal charge balance. In other words, we obtained a synergistic effect from the blending of a linear hole transport polymer [TFB, poly(9,9-dioctylfluorene-co-N-(4-butylphenyl)diphenylamine)] with a new x-HTM that realizes pretty low solubility in common organic solvents as well as significantly enhanced hole transport characteristics. As a result, it gave highly efficient solution-processed green phosphorescent organic light-emitting diodes (PHOLEDs) showing a pretty high current efficiency and external quantum efficiency of approximately 51.6 cd A−1 and 14.6% at the blending ratio of 20% (TFB). Particularly, the device lifetime was remarkably improved by a factor of 6.5 compared to the reference device which used an intrinsic x-HTM. To understand the reason for such outstanding improvement, we performed impedance spectroscopy (IS).

Eu3+-activated WO3-Eu2(WO4)3 luminescent composite thin films are grown on low-cost slide glass substrates by radio frequency sputtering and then annealing in an air atmosphere furnace. The films obtained by sputtering 12 at.% of Eu-added WO3 target afforded a two-phase composite structure comprising Eu-doped WO3 and Eu2(WO4)3 after annealing. The composite thin films annealed at 600 °C exhibited strong red emission after growing at room temperature compared to those annealed at 500 °C under the excitation of 254, 394, and 465 nm corresponding to ultraviolet, near-ultraviolet, and blue light, respectively. The thin films grown at low temperatures without annealing did not emit under ultraviolet light. The crystalline structure, surface morphology, and optical properties, such as transmittance and photoluminescence, of the films grown at 500 °C were almost similar to those of the thin films grown at room temperature when they were annealed at the same temperature. Pure WO3 thin films without Eu doping showed similar crystallization behavior under the same annealing conditions as Eu-added composite films; however, they did not exhibit photoluminescence properties. Our report on the integration of thin-film red phosphors on glass substrates is promising for the development of low-cost and large-area optical devices activated at various excitation wavelengths.

The fabrication of composites consisting of ferromagnetic and ferroelectric complex oxides is important for the development of versatile multifunctional electronic devices. Herein, 0–3 type ceramic (BiFeO3)1-x-(Y3Fe5O12)x (0 ≤ x ≤ 0.3) composites, comprising Y3Fe5O12 particles randomly dispersed in a BiFeO3 matrix, were synthesized via a solid-state reaction. Two phases, BiFeO3 and Y3Fe5O12, were observed without the formation of any secondary phases. With increasing Y3Fe5O12 content in the composites, the leakage current dramatically decreased while the magnetic moment increased. A sputter deposition technique was introduced to grow BiFeO3-Y3Fe5O12 composite thin films on (0 0 1)-oriented SrTiO3 substrates. The BiFeO3-Y3Fe5O12 thin films grown at 650 °C exhibited isotropic magnetic behavior with low magnetization, whereas the magnetic hysteresis loops of the annealed films revealed two distinct slopes. The portion of the steeper slope near the zero field originated from the soft magnetic Y3Fe5O12 and increased with higher annealing temperature. This new fabrication of BiFeO3-Y3Fe5O12 composite thin films is promising to the design of new electronic devices with multifunctional properties.

A series of new bipolar host materials with carbazole and different number of dipyridyl amine groups were synthesized for blue phosphorescent organic light-emitting diodes (PHOLEDs). Especially, we applied dipyridyl amine to control the polarity as well as electron transporting property of the carbazole based host materials for comparison with the properties of 1,3-di(9 H -carbazol-9-yl)benzene (mCP). As a result, all the carbazole based host materials with dipyridyl amine moieties showed very high triplet energies (>2.9 eV) as well as wide band gap (>3.5 eV). Thus, the blue phosphorescent devices employing those materials with bis(4,6-difluorophenyl pyridinato- N,C2 )picolinato-iridium (III) (FIrpic) as a dopant and we obtained moderately high external quantum efficiency (EQE) up to 21.6% with N -(3,5-di( 9H -carbazol-9-yl)phenyl)- N -(pyridin-2-yl)pyridin-2-amine ( DCPPy ).

In this study, an estimation method of graphite dust production in the pebble-bed type reflector region of the Korean Helium Cooled Ceramic Reflector (HCCR) Test Blanket Module (TBM) of the International Thermonuclear Experimental Reactor (ITER) project using Finite Element Method (FEM) was proposed and the total amount of dust production was calculated. A unit-cell model of uniformly arranged pebbles was defined with thermal and mechanical loadings. A commercial FEM program, Abaqus V6.10, was used to model and solve the stress field under multiple contact constraints between pebbles in the unit-cell. Resultant normal contact forces and slip distances on the contact points were applied into the Archard adhesive wear model to calculate the amount of graphite dust. The Finite Element (FE) analysis was repeated at 27 unit-cell locations chosen to form an interpolated dust density function for the entire region of the reflector. The dust production calculation was extended to the life time of the HCCR and the total graphite dust production was estimated to 0.279 g at the end of the life time with the maximum graphite dust density of 0.149 μg/mm3. The dust explosion could be a safety issue with the calculated dust density level and it requires that an appropriate maintenance to remove sufficient amount of graphite dust regularly to prevent the possibility of dust explosion.

These days, technological advances are being made through technological conversion. Following this trend, companies need to adapt and secure their own sustainable technological strategies. Technology transfer is one such strategy. This method is especially effective in coping with recent technological developments. In addition, universities and research institutes are able to secure new research opportunities through technology transfer. The aim of our study is to provide a technology transfer prediction model for the sustainable growth of companies. In the proposed method, we first collected patent data from a Korean patent information service provider. Next, we used latent Dirichlet allocation, which is a topic modeling method used to identify the technical field of the collected patents. Quantitative indicators on the patent data were also extracted. Finally, we used the variables that we obtained to create a technology transfer prediction model using the AdaBoost algorithm. The model was found to have sufficient classification performance. It is expected that the proposed model will enable universities and research institutes to secure new technology development opportunities more efficiently. In addition, companies using this model can maintain sustainable growth in line, coping with the changing pace of society.

This study aims at analyzing the convergence of Internet-of-Things and wearables technologies using cooperative patent classification(CPC). CPC, introduced to an increasing number of technological fields of Korean patents, is expected to be widely used in Patent Informatics because the classification codes in CPC are more specific than those of IPC, which reflect the characteristics of technologies in detail with accuracy. CPC has seldom been used up to date and most of the previous researches on technological convergence used IPC. As a pre-analysis step for analyzing the trend of technological convergence of IoT and wearables, CPC and IPC codes assigned to each patent were compared. By applying association rule mining to the analysis of CPC codes, we identified the technological fields where convergence frequently takes place and examined the trend of technological convergence over time.

Although carboplatin is one of the standard chemotherapeutic agents for non-small cell lung cancer (NSCLC), it has limited therapeutic efficacy due to activation of a survival signaling pathway and the induction of multidrug resistance. Curcumin, a natural compound isolated from the plant Curcuma longa, is known to sensitize tumors to different chemotherapeutic agents. The aim of this study is to evaluate whether curcumin can chemosensitize lung cancer cells to carboplatin and to analyze the signaling pathway underlying this synergism. We investigated the synergistic effect of both agents on cell proliferation, apoptosis, invasion, migration, and expression of related signaling proteins using the human NSCLC cell line, A549. A549 cell was treated with different concentrations of curcumin and carboplatin alone and in combination. Combined treatment with curcumin and carboplatin inhibited tumor cell growth, migration, and invasion compared with either drug alone. Matrix metalloproteinase (MMP)-2 and MMP-9 were more efficiently downregulated by co-treatment than by each treatment alone. mRNA and protein expression of caspase-3 and caspase-9 and proapoptotic genes was increased in cells treated with a combination of curcumin and carboplatin, whereas expression of the antiapoptotic Bcl-2 gene was suppressed. Co-treatment of both agents substantially suppressed NF-κB activation and increased expression of p53. Phosphorylation of Akt, a protein upstream of NF-κB, was reduced, resulting in inhibition of the degradation of inhibitor of κB(IκBα), whereas the activity of extracellular signal-regulated kinase (ERK1/2) was enhanced. Our study demonstrated that the synergistic antitumor activity of curcumin combined with carboplatin is mediated by multiple mechanisms involving suppression of NF-κB via inhibition of the Akt/IKKα pathway and enhanced ERK1/2 activity. Based on this mechanism, curcumin has potential as a chemosensitizer for carboplatin in the treatment of patients with NSCLC.