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Ni–W alloys have received considerable interest as a promising structural material for microelectromechanical systems (MEMS) due to their exceptional properties, including hardness, ductility, corrosion resistance, and thermal stability. However, the electrodeposition of Ni–W alloys in the MEMS fabrication process to achieve intact structures with a thickness of several tens of micrometers is challenging due to the occurrence of cracking caused by side reactions and internal stresses during the electrodeposition process. To address this issue, our focus was on pulsed reverse electrodeposition (PRE) as a potential solution. The utilization of the PRE technique allows for a high concentration of reactive species on the electrode surface, thereby mitigating side reactions such as hydrogen generation. In this study, we examined the effects of the PRE method on the morphological characteristics, average crystal grain size, Vickers hardness, and micro-mechanical properties of Ni–W alloys.

This study reports on the use of supercritical CO2 (scCO2) for the metallization of ultrahigh-molecular-weight polyethylene (UHMW-PE) filaments, which are used as functional components in weavable devices. UHMW-PE is well known for its chemical and impact resistance, making it suitable for use in bulletproof clothing and shields. However, its chemical resistance poses a challenge for metallization. By utilizing scCO2 as the solvent in the catalyzation process, a uniform and defect-free layer of Ni-P is successfully deposited on the UHMW-PE filaments. The deposition rate of Ni-P is enhanced at higher temperatures during the scCO2 catalyzation. Importantly, the durability of the Ni-P-metalized UHMW-PE filaments is improved when the scCO2 catalyzation is carried out at 120 °C, as evidenced by minimal changes in electrical resistivity after a rolling test.

Polyetherimide (PEI) with 3-dimensional (3D) structures is a promising material for applications in electronic devices because of its numerous attractive properties. In the applications of PEI, the low electrical conductivity is often a shortcoming. The electrical conductivity can be improved by a metallization process. Electroless plating is a common metallization process for polymeric materials; however, conventional electroless plating process scarcely provides the metallized PEI. In this work, we overcome this limitation by a supercritical carbon dioxide (scCO2)-assisted electroless NiP plating process. This scCO2-assisted electroless NiP plating allows metallization of PEI with 3D structures and realizes a low electrical resistance suitable for practical use in the electronic devices.

Gold-based micro-electro-mechanical-systems (Au-MEMS) capacitive accelerometers can simultaneously realize high sensitivity and miniaturization because of the high mass density of Au. In order to further improve the sensitivity of the Au-MEMS capacitive accelerometers, Young's modulus of the cantilever-like spring part connected to the movable component is a key parameter. Considering the size effect in the mechanical property of metallic materials on micro-scale, the design of the spring part is expected to reflect their Young's modulus; that is, effective Young's modulus (Eeff). In this study, we clarify effects of the structural designs of the Au-based micro-cantilevers on their Eeff by experiments and finite element analyses (FEA) simulations. The Eeff of the Au micro-cantilevers having Ti/Au multi-layered structures is evaluated by resonance frequency method, which demonstrates the key structural parameters affecting their Eeff. The FEA calculations show a consistent trend with that observed in the experimental results.

In this study, the strain rate dependence in yield strengths of electrodeposited gold micro-pillars is evaluated for the design of movable components in MEMS devices. The micro-pillars are fabricated from electrodeposited gold by focused ion beam system. The strain rate dependence is quantified by the strain rate sensitivity, and the strain rate sensitivity is calculated from the yield strength obtained from compression tests of the gold micro-pillars having different sizes at different strain rates. An increase in the yield strength following a reduction in the pillar size is observed, which is the sample size effect. Also, weakening of the yield strength is observed following a decrease in the strain rate, which is the strain rate dependence, and the strain rate sensitivity of the gold micro-pillars is found be at roughly 0.03.

A gold micro-electro-mechanical-systems (Au-MEMS) capacitive accelerometer having Ti/Au multi-layered structures is a promising device to detect very weak accelerations, such as muscle sounds, because of the high mass density of Au. However, Au is a soft metal, which raises concerns about the structural stability of the Au-MEMS capacitive accelerometers for practical use. In this work, we clarify the key geometric parameters to enhance their long-term structural stability by conducting a long-term vibration test for a total of 240 Ti/Au multi-layered micro-cantilevers with different geometric parameters, such as the length, width, and thickness of the micro-cantilevers, and the number of Ti/Au multi-layered structures. The long-term structural stability is evaluated from the change in the tip height of the micro-cantilevers before and after the vibration tests. These tests demonstrate that the micro-cantilevers with a shorter length, larger thickness, and more Ti/Au multi-layered structures are found to show better long-term structural stability.

Abstract Near infrared energy remains untapped toward the maneuvering of entire solar spectrum harvesting for fulfilling the nuts and bolts of solar hydrogen production. We report the use of Au@Cu7S4 yolk@shell nanocrystals as dual-plasmonic photocatalysts to achieve remarkable hydrogen production under visible and near infrared illumination. Ultrafast spectroscopic data reveal the prevalence of long-lived charge separation states for Au@Cu7S4 under both visible and near infrared excitation. Combined with the advantageous features of yolk@shell nanostructures, Au@Cu7S4 achieves a peak quantum yield of 9.4% at 500 nm and a record-breaking quantum yield of 7.3% at 2200 nm for hydrogen production in the absence of additional co-catalysts. The design of a sustainable visible- and near infrared-responsive photocatalytic system is expected to inspire further widespread applications in solar fuel generation. In this work, the feasibility of exploiting the localized surface plasmon resonance property of self-doped, nonstoichiometric semiconductor nanocrystals for the realization of wide-spectrum-driven photocatalysis is highlighted.

Necking and barreling deformation behaviors occurred simultaneously during the bending test of a single-crystal gold micro-cantilever (sample A) with the loading direction parallel to the [1-10] orientation and the neutral plane parallel to the [110] orientation. In contrast, for another single-crystal gold micro-cantilever, sample B, with the loading direction aligned parallel to the [0.37 −0.92 0.05] orientation and the neutral plane parallel to the [0.54 0.28 0.78] orientation, predominant slip band deformation was noted. Sample A exhibited activation of four slip systems, whereas sample B demonstrated activity in only a single-slip system. This difference suggests that the presence of multiple slip systems contributes to the concurrent occurrence of necking and barreling deformations. Furthermore, variations in the thickness of the micro-cantilevers resulted in observable strengthening, indicating that the effect of sample size is intricately linked to the geometry of the cross-section, which we have termed the “sample geometry effect”.

The COVID‐19 pandemic has underscored the paramount importance of maintaining clean and safe environments. Strengthening environmental purification measures is pivotal for better preparedness and resilience against future health crises. Photocatalytic fibers, due to their versatility and adaptability to various application scenarios, play a pivotal role in the field of environmental purification. In this perspective, light is shed on the pivotal advancements in employing photocatalytic fibers to tackle environmental issues encompassing dye degradation, antibiotics decomposition, heavy metal removal, indoor air purification, and microbial disinfection. These applications hold significant promise in promoting cleaner and healthier environments while aligning with sustainability objectives. However, the implementation of photocatalytic fibers in practical scenarios is not without its challenges. Issues, such as near infrared responsiveness, all‐day active capacity, reusability, and scalability, must be addressed to ensure their reliability and long‐term effectiveness. Potential solutions for surmounting these challenges are also delved, aiming to provide a comprehensive overview for researchers and stakeholders. Exploring new avenues and innovative approaches may pave the way for the widespread deployment of photocatalytic fibers in environmental purification, especially in the post‐pandemic era where the need for clean and safe environments is more evident than ever.

Au-based micro-electro-mechanical-system (Au-MEMS) capacitance accelerometers show high sensitivity by suppressing the mechanical noise because of the high mass density of gold (ρ = 19.3 g/cm3). On the other hand, their long-term reliability suffers from drift phenomena induced by the impurities incorporated in the key component during their fabrication process, such as the gold electroplating step. Herein, impurities in electroplated Au-based components for MEMS capacitive accelerometers are evaluated by thermal desorption spectrometry (TDS) measurements. The TDS measurement reveals that dominant desorption gases from the Au-based component are molecular hydrogen (H2) and water (H2O). These desorption gases are derived from impurities in the electroplated Au-based component, and the amount of these gases is significantly suppressed by a thermal treatment step. In conclusion, this study demonstrates that the electroplated Au-based component contains impurities originated from the fabrication process, and these impurities could be removed by a thermal treatment step.

Wastewater containing synthetic dyes has caused a significant risk to the environment and human health. Among the various methods to treat wastewater, photocatalysis recommends itself as a particularly efficient tool for the removal of dyes from industrial effluents. In this work, Au@Cu2O core@shell nanocrystals with controllable shell thicknesses from 38.1 ± 2.8 (Au@Cu2O-2), 48.1 ± 3.7 (Au@Cu2O-3) to 59.1 ± 4.1 nm (Au@Cu2O-4) have been prepared and immobilized on polyethylene terephthalate (PET) fabrics for applications in photocatalytic degradation of methylene orange (MO). The influence of the shell thickness of Au@Cu2O on the photocatalytic performance of the functionalized PET fabrics has been examined. Among all the samples tested, immobilization of Au@Cu2O-3 rendered PET fabrics the largest photocatalytic activity for MO degradation, achieving an apparent rate constant of MO degradation of 7.43 × 10−3 min−1. A plausible mechanism accounting for the degradation process of MO over the functionalized PET has been proposed based on the results of scavenger experiments. This work has provided a delicate yet practical functional textile paradigm by combining the photocatalytic capability of Au@Cu2O and the adaptable feature of PET fabrics. The findings from this study can deliver a viable idea for the design of versatile textiles with competent photocatalytic capacity for environmental purifications and energy conversion.

High strength Ni matrix TiO2 composites are prepared by co-electrodeposition with an electrolyte composed of Ni Watts bath, surfactants, CO2 in the supercritical fluid state and various sizes of TiO2 particles. The surfactants and supercritical CO2 (SC-CO2) are used to emulsify the aqueous Ni Watts bath to promote the incorporation of TiO2 particles into the Ni matrix. TiO2 particles with three different average sizes are used in the co-electrodeposition to evaluate the effect on properties of the Ni-TiO2 composites. The grain sizes of the Ni matrix in the composites are compared from the X-ray diffraction results and the Scherrer eq. A refined average grain size in the Ni matrix is observed when using TiO2 particles with a larger size. The TiO2 is evaluated by energy-dispersive X-ray spectroscopy (EDX), and the TiO2 distribution is quantified by the coefficient of variation (cov) of the local density of Ti from the EDX result. The TiO2 content attained 4.5 wt% with the lowest cov value (which suggests the most uniform distribution) in the composite when the smallest (21 nm) TiO2 particles are used. The TiO2 content achieves 22.3 wt% with the highest cov value (which suggests the least uniform distribution) when the largest (5 μm) TiO2 particles are used. Microhardness of the Ni-TiO2 composites is found to be highly depended on the cov value. Hence, the Ni-TiO2 composite prepared with the smallest TiO2 particles shows the highest microhardness at 1274 HV.

Nickel–cobalt alloys were prepared by alloy electrodeposition with a sulfamate bath, and the mechanical properties on the micro-scale were evaluated for the application as micro-components in miniaturized electronic devices. Nickel bromide and a commercially available surface brightener were used as the additives. The cobalt content increased from 21.5 to 60.1 at.% after addition of nickel bromide into the bath, and the grain size refined from 21.1 to 13.2 nm when the surface brightener was used. The mechanical properties on the micro-scale were evaluated by micro-compression test using micro-pillar type specimens fabricated by a focused ion beam system to take the sample size effect into consideration. The yield strength of the nickel–cobalt alloy having an average grain size at 13.9 nm and cobalt content of 66.6 at.% reached 2.37 GPa, revealing influences from the sample size, grain boundary strengthening, and solid solution strengthening effects.

Abstract Although electrostatic actuators have a simple structure and are lightweight, their range of application is limited because a high applied voltage of more than several kilovolts is required for practical use. Since the force acting between the electrodes of an electrostatic actuator is determined by the electric charge accumulated at the electrode/dielectric interface, the focus is on spontaneous polarization of ferroelectrics to increase the charge. As the ferroelectric material, a nematic liquid crystal material with a spontaneous polarization of 5 µC cm−2 is used. It is demonstrated that a force of 1.3 N is generated at an applied electric field of 0.5 MV m−1. This force is 1200 times higher than that for standard paraelectric materials with a dielectric constant of ten. Further, the generated force responds linearly to the applied voltage, whereas it is proportional to the square of the applied voltage for paraelectric materials. The actuator function of this ferroelectric is examined using a double‐helical coil electrode fabricated using a 3D printer. It can be successfully operated at a voltage of several tens of volts. Under an electric field of 0.25 MV m−1, a remarkable contraction of 6.3 mm occurs, corresponding to 19% of the original length.

This study reports the micro-mechanical property and sample size effect in Ni-TiO2 composites (NTO) fabricated by supercritical CO2 emulsified co-electroplating (SCNTO). NTO by conventional co-electroplating (CVNTO) is also prepared as a comparison. The micro-mechanical property is evaluated by micro-compression test of micro-pillars prepared from the NTO by focus ion beam system. Cross-sections of the micro-pillars are 5 μm × 5 μm, 7.5 μm × 7.5 μm and 10 μm × 10 μm, and the height is kept twice of one side of the cross-section. The yield strength of a SCNTO micro-pillar with the dimensions of 7.5 μm × 7.5 μm × 15 μm is 3.37 GPa, which is three times higher than that of the CVNTO. The sample size effect is not observed in the SCNTO micro-pillars, while a smaller-is-weaker effect is observed in the CVNTO micro-pillars. The ultrafine (

Platinum metallization of polyethylene terephthalate (PET) textile is realized by a supercritical carbon dioxide catalyzation process using palladium (II) hexafluoroacetylacetonate as the source of Pd catalyst, and ε-caprolactam as an additive. A commercially available Pt electroless plating solution is used to deposit Pt on the catalyzed PET textile. Surface morphology of the Pt metallized PET textile changes from granular particle to plate-like morphology when the Pt deposition time increases from 1 to 40 min. The Pt layer thickness reaches 270 nm, 580 nm, and 780 nm after 20 min, 60 min and 240 min, respectively, of the Pt deposition time. The Pt metallized PET textile prepared with 240 min of the Pt deposition time shows the lowest electrical resistance at 0.4 Ω, and the electrical resistance merely increases to 0.7 Ω and 1.0 Ω after one and two times, respectively, of a tape adhesion test.

Ti/Au multi-layered micro-cantilevers with complex three-dimensional structures used as micro-components in micro-electromechanical systems (MEMS) sensors were prepared by lithography and electrodeposition, and the effective Young’s modulus was evaluated by the resonance frequency method and finite element method simulation. Effects of the constraint condition at the fixed-end of the micro-cantilever and the temperature dependency of the effective Young’s modulus were studied. Three types of the constraint at the fixed-end were prepared, which were normal type (constraining only bottom surface of the fixed-end), block type (constraining both top and bottom surfaces), and bridge type (top surfaces covering with a bridge-like structure). The temperature dependency test was conducted in a temperature range from 150 to 300 °C in a vacuum chamber. An increase in the effective Young’s modulus was observed as the constraint condition became more rigid, and the effective Young’s modulus merely changed as the temperature varied from room temperature to 300 °C.

Polyethylene terephthalate (PET) is known to be highly inert, and this makes it difficult to be metallized. In addition, Pt electroless plating is rarely reported in the metallization of polymers. In this study, the metallization of biocompatible Pt metal is realized by supercritical CO2 (sc-CO2)-assisted electroless plating. The catalyst precursor used in the sc-CO2 catalyzation step is an organometallic compound, palladium (II) acetylacetonate (Pd(acac)2). The electrical resistance is evaluated, and a tape adhesion test is utilized to demonstrate intactness of the Pt layer on the PET film. The electrical resistance of the Pt/PET with 60 min of the Pt deposition time remains at a low level of 1.09 Ω after the adhesion test, revealing positive effects of the sc-CO2 catalyzation step. A tensile test is conducted to evaluate the mechanical strength of the Pt/PET. In-situ electrical resistances of the specimen are monitored during the tensile test. The fracture strength is determined from the stress value when the short circuit occurred. The fracture strength is 33.9 MPa for a specimen with 30 min of the Pt deposition time. As the Pt deposition time increases to 45 min and 60 min, the fracture strengths reach 52.3 MPa and 65.9 MPa, respectively. The promoted fracture strength and the decent electrical conductivity demonstrate the advantages toward biomedical devices.

Photoelectrochemical (PEC) water splitting supplies an environmentally friendly, sustainable approach to generating renewable hydrogen fuels. Oxides semiconductors, e.g. TiO2, BiVO4, and Fe2O3, have been widely developed as photoelectrodes to demonstrate the utility in PEC systems. Even though significant effort has been made to increase the PEC efficiency, these materials are still far from practical applications. The main issue of metal oxides is the wide bandgap energy that hinders effective photons harvesting from sunlight. In solar spectrum, over 40% of the energy is located in the near-infrared (NIR) region. Developing sophisticated PEC systems that can be driven by NIR illumination is therefore essential. This review gives a concise overview on PEC systems based on the use of NIR-driven photoelectrodes. Promising candidates as efficient yet practical NIR-responsive photoelectrodes are suggested and discussed. Future outlooks on the advancement of PEC water splitting are also proposed.

In this study, a non-enzymatic glucose composed of gold nanoparticle decorated polypyrrole (PPy) is reported. The PPy is prepared by electro-polymerization in 0.05 M phosphate-buffered saline (PBS) containing 0.1 M pyrrole monomer. The gold nanoparticles are decorated by directly dropping 0.1 mM KAuCl4 solution onto the PPy coated electrode. No enzymes are used in preparation of the catalytic electrode. The amount and size of the gold nanoparticles are both found to be dependent on amount of the KAuCl4 solution dropped onto the PPy electrode. The glucose sensing performance is evaluated by cyclic voltammetry in 0.05 M PBS containing 5 mM of glucose with pH at 7.4. The catalytic activity in the oxidation of glucose is confirmed when using the gold nanoparticle decorated PPy as the catalytic electrode, and the performance is found to be affected by the amount of KAuCl4 solution used in preparation of the electrode.

Colletotrichum scovillei causes anthracnose of chili pepper in many countries. Three strains of this pathogen, Coll-524, Coll-153, and Coll-365, show varied virulence on chili pepper. Among the three strains, Coll-365 showed significant defects in growth and virulence. To decipher the genetic variations among these strains and identify genes contributing to growth and virulence, comparative genomic analysis and gene transformation to show gene function were applied in this study. Compared to Coll-524, Coll-153, and Coll-365 had numerous gene losses including 32 candidate effector genes that are mainly exist in acutatum species complex. A cluster of 14 genes in a 34-kb genomic fragment was lost in Coll-365. Through gene transformation, three genes in the 34-kb fragment were identified to have functions in growth and/or virulence of C. scovillei. CsPLAA encoding a phospholipase A2-activating protein enhanced the growth of Coll-365. A combination of CsPLAA with one transcription factor CsBZTF and one C6 zinc finger domain-containing protein CsCZCP was found to enhance the pathogenicity of Coll-365. Introduction of CsGIP, which encodes a hypothetical protein, into Coll-365 caused a reduction in the germination rate of Coll-365. In conclusion, the highest virulent strain Coll-524 had more genes and encoded more pathogenicity related proteins and transposable elements than the other two strains, which may contribute to the high virulence of Coll-524. In addition, the absence of the 34-kb fragment plays a critical role in the defects of growth and virulence of strain Coll-365.

Abstract Background Along with the rapid development of glycomic tools, the study of lectin–carbohydrate interactions has expanded, opening the way for applications in the fields of analytic, diagnostic, and drug delivery. Chitin-binding lectins (CBLs) play roles in immune defense against chitin-containing pathogens. CBLs from species of the Solanaceae family, such as tomato, potato and jimsonweed, display different binding specificities to sugar chains containing poly-N-acetyllactosamine. Results In this report, CBLs from Solanum integrifolium were isolated by ion exchange chromatography. The fractions showed hemagglutination activity (HA). The recombinant CBL in the 293F cell culture supernatant was able to inhibit the growth of Rhizoctonia solani and Colletotrichum gloeosporioide. Furthermore, the carbohydrate-binding property of CBLs was confirmed with the inhibition of HA. Binding of CBL to Spodoptera frugiperda (sf21) insect cells can partly be inhibited by N-Acetylglucosamine (GlcNAc), which is related to decrease mitochondrial membrane potential of sf21 cells. Conclusions The results showed that CBL exhibited antifungal properties and inhibited insect cell growth, which is directly correlated to the lectin-carbohydrate interaction. Further identification and characterization of CBLs will help to broaden their scope of application in plant defense and in biomedical applications.

A frequency beam splitter (FBS) with the split ratio of 0.5, i.e., 50/50 FBS, can be used as the frequency-mode Hadamard gate for frequency-encoded photonic qubits. A FBS with the split ratio of 1 is exactly the coherent frequency converter (CFC) for frequency up or down conversion of photons. Previous works revealed that all kinds of 50/50 FBS and CFC operating at the single-photon level had overall efficiency or output-to-input ratio around 50% or less. In this work, our 50/50 FBS and CFC are made with the four-wave mixing (FWM) process based on the double-Λ electromagnetically induced transparency (EIT) scheme. We achieved an overall efficiency of 90 ± 4% in the 50/50 FBS and that of 84 ± 4% in the CFC using coherent-state single photons, both of which are the best up-to-date records. Furthermore, we utilize the scheme of Hong-Ou-Mandel interference (HOMI) to measure the fidelity or degree of coherence of the FBS. The fidelity indicated by the HOMI's g^{(2)} measurement of the 50/50 FBS is 0.99 ± 0.01. This high fidelity demonstrates the low noise of the frequency conversion in the EIT-based FWM process. Such low-loss high-fidelity FBS with the tunable split ratio can lead to useful operations or devices in long-distance quantum communication.

The aim of this study is to investigate a characteristic deformation behavior of a precipitation strengthening-type Cu-Ni-Si alloy (Cu-2.4Ni-0.51Si-9.3Zn-0.15Sn-0.13Mg) by microcompression specimens. Three micropillars with a square cross-section of 20 × 20 × 40 μm3 were fabricated by focused ion beam (FIB) micromachining apparatus and tested by a machine specially designed for microsized specimens. The three pillars were deformed complicatedly and showed different yield strengths depending on the crystal orientation. The micromechanical tests revealed work hardening by the precipitation clearly. Electron backscattered diffraction analysis of a deformed specimen showed a gradual rotation of grain axis at the grain boundaries after the compression test.

The Gram-negative bacterium Pseudomonas taiwanensis is a novel bacterium that uses shrimp shell waste as its sole sources of carbon and nitrogen. It is a versatile bacterium with potential for use in biological control, with activities including toxicity toward insects, fungi, and the rice pathogen Xanthomonas oryzae pv.oryzae (Xoo). In this study, the complete 5.08-Mb genome sequence of P. taiwanensis CMS was determined by a combination of NGS/Sanger sequencing and optical mapping. Comparison of optical maps of seven Pseudomonas species showed that P. taiwanensis is most closely related to P. putida KT 2400. We screened a total of 11,646 individual Tn5-transponson tagged strains to identify genes that are involved in the production and regulation of the iron-chelator pyoverdine in P. taiwanensis, which is a key anti-Xoo factor. Our results indicated that the two-component system (TCS) EnvZ/OmpR plays a positive regulatory role in the production of pyoverdine, whereas the sigma factor RpoS functions as a repressor. The knowledge of the molecular basis of the regulation of pyoverdine by P. taiwanensis provided herein will be useful for its development for use in biological control, including as an anti-Xoo agent.

Hierarchical structures of 20 nm grains embedded with twins are realized in electrodeposited Au−Cu alloys. The electrodeposition method allows refinement of the average grain size to 20 nm order, and the alloying stabilizes the nanoscale grain structure. Au−Cu alloys are face-centered cubic (FCC) metals with low stacking fault energy that favors formation of growth twins. Due to the hierarchical structure, the Hall−Petch relationship is still observed when the crystalline size (average twin space) is refined to sub 10 nm region. The yield strength reaches 1.50 GPa in an electrodeposited Au−Cu alloy composed of 16.6 ± 1.1 nm grains and the average twin spacing at 4.7 nm.

Due to its low cost, environmentally friendly process, and lack of secondary contamination, the photodegradation of dyes is regarded as a promising technology for industrial wastewater treatment. This technology demonstrates the light-enhanced generation of charge carriers and reactive radicals that non-selectively degrade various organic dyes into water, CO2, and other organic compounds via direct photodegradation or a sensitization-mediated degradation process. The overall efficiency of the photocatalysis system is closely dependent upon operational parameters that govern the adsorption and photodegradation of dye molecules, including the initial dye concentration, pH of the solution, temperature of the reaction medium, and light intensity. Additionally, the charge-carrier properties of the photocatalyst strongly affect the generation of reactive species in the heterogeneous photodegradation and thereby dictate the photodegradation efficiency. Herein, this comprehensive review discusses the pseudo kinetics and mechanisms of the photodegradation reactions. The operational factors affecting the photodegradation of either cationic or anionic dye molecules, as well as the charge-carrier properties of the photocatalyst, are also fully explored. By further analyzing past works to clarify key active species for photodegradation reactions and optimal conditions, this review provides helpful guidelines that can be applied to foster the development of efficient photodegradation systems.

Previously we developed genomic resources for orchids, including transcriptomic analyses using next-generation sequencing techniques and construction of a web-based orchid genomic database. Here, we report a modified molecular model of flower development in the Orchidaceae based on functional analysis of gene expression profiles in Phalaenopsis aphrodite (a moth orchid) that revealed novel roles for the transcription factors involved in floral organ pattern formation. Phalaenopsis orchid floral organ-specific genes were identified by microarray analysis. Several critical transcription factors including AP3, PI, AP1 and AGL6, displayed distinct spatial distribution patterns. Phylogenetic analysis of orchid MADS box genes was conducted to infer the evolutionary relationship among floral organ-specific genes. The results suggest that gene duplication MADS box genes in orchid may have resulted in their gaining novel functions during evolution. Based on these analyses, a modified model of orchid flowering was proposed. Comparison of the expression profiles of flowers of a peloric mutant and wild-type Phalaenopsis orchid further identified genes associated with lip morphology and peloric effects. Large scale investigation of gene expression profiles revealed that homeotic genes from the ABCDE model of flower development classes A and B in the Phalaenopsis orchid have novel functions due to evolutionary diversification, and display differential expression patterns.