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In this paper we report the synthesis and crystal structures of emissive organic molecule (1a) based on pyrido[3,4-g]isoquinoline framework as well as its isomers 1b and 1c. The emission quantum yields decrease after transformation of pyridine moieties in 1a into the cyclic-amides in 1b and 1c. The fluorescent spectral results reveal that 1a, 1b, and 1c exhibit no AIE behavior. This is tentatively attributed to intramolecular weak C⋯H interactions, which may impede the intramolecular rotations based on the crystal structures of 1a and 1c. Interestingly, 1a, 1b, and 1c are emissive in the solid state, and among them 1a possesses the highest emission quantum yield (0.22). Moreover, the fluorescence of 1a in solution and solid state can be reversibly tuned by reactions with trifluoroacetic acid and triethylamine. Microarea PL studies reveal that microrods of 1a and these after exposure to HCl gas show typical waveguide behavior.

A novel approach to manipulating multiple optical signals at subwavelength scale is proposed in dendritic organic/metal nanowire heterostructures. The heterostructures are prepared by embedding Ag nanowires in fac-tris(2-phenylpyridine) iridium microwires during the self-assembly in liquid phase. Optical signals inputted from the organic waveguide can be selectively transferred to the predetermined subwavelength output ports based on the angular dependence of the photon-plasmon coupling.

The definition of concrete-filled steel tube and structural characteristics are introduced briefly. On the high bearing capacity of concrete-filled steel tube structure，economy and ease of construction are analyzed and summed up. This paper expounds the general situation of the development of concrete-filled steel tube and research progress.

Perovskite single-crystalline microplate arrays are directly achieved in large scale by inkjet printing, which present high performance lasing property with quality factors up to 863 and RGB (red-green-blue) emission. This facile, nonlithographic method makes its promising applications on multi-integrated coherent light sources and other high-performance integrated optoelectronic applications.

Nanophotonics have recently captured broad attention because of their great potential in information processing and communication, which may allow rates and bandwidth beyond what is feasible in the realm of electronics. Organic materials could be well suitable for such applications due to their ability to generate, transmit, modulate and detect light in their lightweight and flexible nanoarchitectures. Their distinct nanophotonic properties strongly depend on their extrinsic morphologies and intrinsic molecular excited-state processes. In this feature article, we mainly focus on a comprehensive understanding of the relationship between molecular excited-state processes and the advanced photonic functionalities of organic micro/nano-crystals in recent organic nanophotonic research, and then expect to provide enlightenment for the design and development of tiny photonic devices with broadband tunable properties by tailoring the excited-state processes of organic microcrystals.

A wavelength-tunable microlaser is realized based on the controlled intramolecular charge transfer (ICT) process in dye-encapsulated metal-organic framework (MOF) material. The confinement effect of the MOFs is beneficial for low-threshold lasing. By effectively controlling the polarity of the MOF pores, the population distribution between the locally excited and ICT states is continuously modulated, thus achieving broadband tunable MOF-based microlasers.

Wavelength-tunable micro/nanoscale lasers are particularly attractive as indispensible building blocks for various ultracompact photonic devices. Polymorphic organic materials display distinct emission colors in different crystal forms, providing the potential possibility in tailoring the lasing wavelength. Here we report wavelength-controlled microlasers based on the polymorphism-dependent intramolecular charge-transfer (ICT) process in organic microcrystals. With different solution-phase self-assembly methods, three kinds of microstructures were prepared from the same organic ICT compound, where the different crystal structures offer completely distinct molecular environments, having a significant influence on the excited-state ICT process and therefore the emission wavelength. As a result, we realized three different color lasing actions in these three kinds of organic ICT microcystals under two-photon pumping. The results demonstrated here provide useful insights for the rational design of miniaturized lasers with desired performances.

Superwettability of substrates has had a profound influence on the production of novel and advanced colloidal assemblies in recent decades owing to its effect on the spreading area, evaporation rate, and the resultant assembly structure. In this paper, we investigated in detail the influence of the superwettability of a transfer/template substrate on the colloidal assembly from a hybrid top-down/bottom-up strategy. By taking advantage of a superhydrophilic flat transfer substrate and a superhydrophobic groove-structured silicon template, the patterned colloidal microsphere assembly was formed including linear and mesh-, cyclic-, and multistopband assembly arrays of microspheres, and the optic-waveguide of a circular colloidal structure was demonstrated. We believed this liquid top-down/bottom-up strategy would open an efficient avenue for assembling/integrating microspheres building blocks into device applications in a low-cost manner.

The synthesis and optical investigations of di(p-methoxylphenyl)dibenzofulvene (1) and its analogues 2, 3, 4, 5, 6, and 7 with different lengths of alkoxyl chains are presented. All of these molecules exhibit emission in the solid state. The following interesting properties are reported for compound 1: 1) the solid-state fluorescence of 1 is dependent on the polymorphism forms; the two crystalline forms 1a and 1b are strongly blue- and yellow-green-emissive, whereas the amorphous solid is weakly fluorescent with orange emission; 2) on the basis of crystal-structural analysis, the intermolecular interactions will restrict the internal rotations, leading to fluorescence enhancement for the two crystalline forms 1a and 1b; however, the difference in emission color between 1a and 1b is ascribed to the molecular conformational alteration; 3) the solid-state fluorescence of 1 can be tuned by heating and cooling as well as grinding. Importantly, microrods of 1a and 1b exhibit outstanding optical waveguide behaviors. Moreover, amplified spontaneous emission for 1b and multimode-lasing behavior for 1a are presented. Besides the studies of compound 1, the crystal structures and solid-state fluorescence behaviors of 2, 3, 4, 5, 6, and 7 are also described.

Processes that control the distribution and natural attenuation (NA) of petroleum hydrocarbons dissolved from the released diesel fuel in a bench-scale model aquifer were evaluated. The experimental results obtained in two-dimensional aqueous-phase petroleum hydrocarbon concentrations indicated that the total petroleum hydrocarbon (TPH) in the aquifer migrated in longitudinal and lateral directions. The TPH plume of 2 mg L−1 spread to the entire area of the aquifer, and the maximum concentration at the center of the plume was 44.15 mg L−1 after 90 days of release. After diesel fuel release, the NA of TPH was evaluated and quantified. Experimental data indicated that the NA of TPH was immediately implemented to prevent migration of the plume into the downgradient of the aquifer, but controlling the TPH plumes using NA mechanisms requires a long time.

In the presence of trifluoroacetic acid and methanesulfonic acid (MSA), a series of monohydric and polyhydric phenols readily undergo a domino Pechmann–dehydration reaction with various 4-hydroxy-6-oxocyclohexane-1,3-dicarboxylates to give 7,8-dihydro-6H-dibenzo[b,d]pyran-6-ones. Subsequent dehydrogenation of the 7,8-dihydro-6H-dibenzo[b,d]pyran-6-ones was performed expediently with DBU/BrCCl3 to give various 6H-dibenzo[b,d]pyran-6-one derivatives. This strategy has the advantages of inexpensive and easily available raw materials, metal-free procedure, mild reaction conditions, good compatibility with various functional groups, and satisfactory yields.

Anaerobic fermentative technology is an important route to solving environmental pollution and resources problems. Combined hydrogen and methane production in a two-stage process is a concept which has been developed in recent years Anaerobic biological treatment organic wastewater can produce large amounts of hydrogen and methane，which can be used as energy carrier. At present，the research focusing on the adjustment of fermentation hydrogen-methane production has been conducted. Furthermore, the simultaneous hydrogen-methane production was tested and optimized. However, it lacked combined hydrogen-methane production in an anaerobic reactor in literature so far. Based on preview experiment, the paper studied the simultaneous hydrogen-methane fermentation in an anaerobic baffled reactor (ABR) system. ABR has the advantage of biomass phase separation and integration of acidogenic and methanogenic processes to simultaneously conduct hydrogen-methane production during wastewater treatment. Through deep biohydrogen production, it can enhance the activity of hydrogen-producing acetogens (HPA) and the efficiencies of the combined hydrogen-methane fermentation system. It showed to enhance the activity of HPA was the key to the combined hydrogen-methane production.

A novel amphiphilic porphyrin derivative DOCP-Zn has been synthesized and utilized to construct tunable nanostructures from 0D to 1D by controlling the axial coordination of zinc porphyrin with 4,4′-bipyridine. SEM images indicated that patterns between 0D nanospheres and 1D nanorods or nanoslices can be reversibly converted by the construction or destroy of the axial coordination interaction. This facile approach provided a new method for controlling the nanostructure morphologies and dimension by patterns conversion. The photoluminescence microscopy images indicated the 1D nanorods material has the potential application as nanoscale photonic elements.

Organic/organic single-crystal coaxial p-n heterojunction nanowire arrays consisting of p-type copper phthalocyanine (CuPc) and n-type 5,10,15,20-tetra(4-pyridyl)-porphyrin (H(2)TPyP) are fabricated through a one-step physical vapor transport (PVT) process. Each single junction wire revealed high photodependent rectifying and sensitive photoresponsive characteristics in devices of light-controlled diodes and photoswitches. The typical photovoltaic device based on a single p-n junction exhibited a high open-circuit voltage (Voc) of 0.64 V.

Organic photonic heterostructures are constructed through a template-free self-assembly method. The host-guest intermolecular interactions play an essential role in the formation of various block orange-blue-orange and blue/green microtubes. The spatial distribution of excitons is engineered to investigate the excitonic behaviors in light propagation along the axial heterostructures. These results offer a new route to the integration of organic photonic building blocks for optical processing applications.

The transparent bulk polymer nanocomposites blended with rare earth nanoparticles are prepared through the radical polymerization of trimethylolpropane trimethylacrylate (TMPTMA). These materials produce continuously tunable second harmonic (SH) radiation under illumination of a wide spectral range of fundamental waves (750-850 nm). The SHG efficiency can be controlled well by altering the Tb(3+) doping content in the nanoparticles.

Due to their potential performances in photonic integrations, one-dimensional single-crystalline nanostructures constructed from organic luminescent molecules have generated wide research interests during the past few years. Here, we highlight the two main kinds of applications in the future of miniaturized photonic circuits: optical waveguides and optically pumped lasers. This article concludes with a summary and our personal view about the direction of future development in organic opto-functional waveguides and lasers as photonic devices.

To investigate the influence of illumination on the fermentative hydrogen production system, the hydrogen production efficiencies of two kinds of anaerobic activated sludge (floc and granule) from an anaerobic baffled reactor were detected under visible light, dark and light-dark, respectively. The 10 mL floc sludge or granular sludge was respectively inoculated to 100 mL diluted molasses (chemical oxygen demand of 8000 mg·L−1) in a 250 mL serum bottle, and cultured for 24 h at 37°C under different illumination conditions. The results showed that the floc was more sensitive to illumination than the granule. A hydrogen yield of 19.8 mL was obtained in the dark with a specific hydrogen production rate of 3.52 mol·kg−1MLVSS·d−1 (floc), which was the highest among the three illumination conditions. Under dark condition, the hydrogen yield of floc sludge reached the highest with the specific hydrogen production rate of 3.52 mol·kg−1MLVSS·d−1, and under light-dark, light, the specific hydrogen production rate was 3.11 and 2.21 mol·kg−1MLVSS·d−1, respectively. The results demonstrated that the illumination may affect the dehydrogenase activity of sludge as well as the activity of hydrogen-producing acetogens and then impact hydrogen production capacity.

In this paper, the contents, meaning and importance of conceptual design in the high-rise building structure design are explored from the following respects: structural system, facade layout and multi-channel seismic line. It not only provides a strong protection of concept for calculation of high-rise building structures, but also accumulates some experience for the research on conceptual design of high-rise structures.

One-dimensional (1D) nanomaterials synthesized from opto-functional low-molecular-weight organic compounds have drawn great interests for their unique optical properties and potential applications in high speed miniaturized photonic integrations. Compared with their inorganic counterparts, organic nanostructures offer advantages such as their high reactivity, ease of chemical doping and convenience in processing at low temperature. In this article, we begin with a general overview of recent progress in this research area. After that, the construction strategies for achieving 1D nanostructures from small organic functional molecules are introduced. Then we focus on the unique optical properties induced by molecular aggregation in the nanostructures, such as optical waveguide, stimulated emission and electroluminescence. This article concludes with a summary and our perspective about future development in 1D organic molecular nanomaterials and organic integrated photonic devices.

Due to nonlinearity, preload-dependent spring force and parameters uncertainty in air spring, it is difficult to control this suspension system. To achieve a desired performance, a fuzzy sliding mode controller (FSMC) has been designed to improve the passenger comfort and manipulability of vehicle, in which the fuzzy adaptive system is used to deal with the nonlinearity and uncertainty of the air suspension. A normal linear suspension model with an optimal state feedback control is designed as the reference model. The simulation results show that this control scheme is more effective and robust in the vibration isolation of the vehicle body than is the conventional sliding mode controller (CSMC).

The bearing stiffness model is established based on the Hertz contact theory and the hydrodynamic lubrication theory of rolling bearing in this paper, the dynamic characteristics of the angular contact ball bearing and the relationship between the bearing preload, the speed and the stiffness of the angular contact ball bearing is analyzed, as well as the influence of the oil film stiffness on the bearing total stiffness. The results from taking 71924ACD/P4A bearing as an example shows that the preload and the speed have important effect on the stiffness of bearing. By the contrast of two kinds of situations, a conclusion can be drawn that when considering the oil film stiffness,the total stiffness reduces 0-40% than not considering the oil film stiffness.

The structure of an organic dye 1,5-diaminoanthraquinone (DAAQ) nanowire was studied by both electron diffraction and X-ray powder diffraction. The unit cell of the crystal was determined from a series of tilted selected area electron diffraction patterns (monoclinic: a =3.78 A, b =9.73 A, c =15.01 A and β =82.4°). By using precession electron diffraction, the following extinction conditions were determined, 0 k 0: k =2 n and 00 l : l= 2 n , which give the space group as P 2 1 / C (no. 14). The powder charge flipping algorithm was applied to resolve the phase problem and the structural model of the DAAQ crystal was built.

This paper has proposed a new structure of lateral diagonal tensile piezoelectric driving feeder which based on the study of foreign advanced technology of piezoelectric feeding devices. It has analysed the driving source and material movement properties of the new structure, and carried out the experimental research and analysis that based on the theoretical analysis. According to these, we get the relationships between driving voltage and feeding speed, frequency and feeding speed and the relationships among voltage, frequency and driving current. Measuring the driving power and compared with the electromagnetic vibration feeder, we obtained that the piezoelectric driving feeder’s energy-saving effect is remarkable. The whole machine has the superior performance.

The natural attenuation process was studied by vadose zone simulating indoor to quantify the adsorption, biodegradation and volatilization of diesel oil. Through adsorption experiment, adsorption equilibrium time of diesel sewage by fine sand was 24 h, and maximum theoretical adsorbance to Total Petroleum Hydrocarbon (TPH) was calculated to 234 mg/kg. Through the contrasts of three columns, the first-order attenuation kinetics equations of biodegradation and volatilization in the diesel polluted sand layer of vadose zone and the half-life time were established. According to the experiments, absorption, biodegradation and volatilization all played important roles, they were very major roles in natural attenuation.

Study on migration and transformation rules of diesel fuels pollution by using two-dimensional plexiglass tank to simulate underground aquifers. Through regular monitoring of the sampling ports in total petroleum hydrocarbon content of the water to determine the diesel fuels in the medium sand aquifer in the migration process, and compute out parameters of diesel fuels pollution in the medium sand aquifer in the mathematical model of migration. This prediction of diesel fuels pollution in the migration of sand media. The results showed: the highest values of different sampling ports used by the time its location is closely related to distance to sources, the concentration rose to the highest value used in a short time. The sampling ports far away from the pollution spilling place rose to the highest value of concentration used in a long time. After diesel fuels leaked 40 d later, the simulation of pollutants reached the bottom slot, and diesel fuels can be calculated transfered with a speed of 1cm•d-1, and then after 20 d more, TPH can be moved to simulate the water tank side pollution of the aquifer region.

Comparative experiment of 3 medium sand columns was executed to research the influence of water content on natural attenuation of diesel fuels contaminated vadose zone. The results showed that: The lower the water content, the stronger capacity of retarding diesel fuels was. After a diesel fuels spill, the average concentration of TPH were 57.7 g•kg-1, 47.55 g•kg-1 and 31.95 g•kg-1 in medium sand with different water content (0.66 %, 8.00 % and 15.22 %). Besides, the TPH found 90 days after the natural attenuation degradated by 38 % and 44.62 % 4 of the initial contaminant load of the medium sand with water content 0.66 % and 8.00 %. Additionally, the higher the water content, the larger the microbial activity of sand was. Biodegradation was the important mechanism for natural attenuation of diesel fuels.

Fenton and Fenton-like reactions are regarded as high efficient methods in advanced treatment of nitrobenzene wastewater but both restrained in degradation of nitrobenzene in groundwater because of the low pH condition( less than 4 ) requirement and other problems such as secondary pollution by the irons in contaminated sites. This paper reports a new Fenton-like technology combined irons extraction from aquifer materials which were found in a nitrobenzene contaminated site in China with hydrogen peroxide catalytic oxidation. The simulate experiments were conducted to investigate the oxidation of nitrobenzene in groundwater by this method under the condition of neutral pH and 8~10°C. The comparison of different extraction agent and production rule of hydroxyl radical were both studied in this research. The results indicated that extraction had hysteresis property because the highest extracting efficiency occurred after 36h. Extraction agent DCB has the highest efficiency, for Fe3+ was 62.92% and Fe2+ was 30.17%. The highest removal efficiency could reach 80.2% while the mole ratio of nitrobenzene to H2O2 was 1:200. Three stages could found in hydroxyl radical generation process, in the first stage hydroxyl radical generated rapidly in 0~30min, then decreased slowly between 30min and 120min, at last the generation tended to be steady after 120h. The results could possess a good potential for application in the treatment of nitrobenzene contaminated groundwater and provide theoretical basis on in-situ chemical remediation technology of nitrobenzene contaminated sites.

Natural attenuation of BTEX and characteristics of the water in the study are researched in this paper. The study not only obtain the attenuation rules of BTEX over time, but also the rules of the redox materials of the contaminated groundwater over time. From the study, we reach conclusion that the redox conditions is changed with the increasing pollution of BTEX and the oxidation condition changes into reducing condition. With the changing of the redox condition, there take place a variety of redox reactions. The materials of oxidation, such as O2, NO3-, Fe3+and SO42-, are transformed into reduction materials, such as NO2-, Fe2+, S2- and so on. In this process, the components of BTEX are degradated by micro-organisms which using the oxidation materials as electron acceptors.

This paper deals with the influencing factors on removal of diesel oil from by soil vapor extraction (SVE) method. A series of one-dimensional column experiments were conducted to study the influencing factors for SVE method, the factors included extracted vapor flow rate,water content and the concentration of the contaminant. The results indicated that: (1) the increase of vapor flow rate led to higher contaminant removal efficiency,but the increment of removal was not significant at higher flow rate levels;(2) the moisture content is 12% coarse sand elimination rate is bigger than 1% coarse sand;(3) the soil index of oil is higher, the extraction time to be longer, it is not suitable processes with SVE that the diesel oil density is excessively low.

Exciton–polaritons arising from strong coupling between excitons and photons are composite bosons which are half light and half matter. Due to their relatively light effective mass (seven orders of magnitude less than the mass of a hydrogen atom), they could potentially condense at temperatures much higher than those required for atom Bose–Einstein condensations (tens of nanokelvins). This makes them not only a perfect model for fundamental studies of dynamical Bose–Einstein condensates, but also a suitable system for the design of novel optical components. Various polaritonic devices such as polariton parametric amplifiers, optically pumped polariton lasers and polariton light-emitting diodes have been achieved. With the recently reported electrically pumped polariton lasers added to the list, the polaritons seem to have made their way out of the laboratory and have a bright, white future ahead.

In this paper, a design method of software simulated SCIs has been proposed to resolve the problem that the built-in SCIs of the MCU could not meet the need of data communications in the research and development of the yacht monitoring system. Two simulated SCIs have been established through building hardware circuits and writing software programs by using the parallel I/O ports and the enhanced capture timer of the MCU. Meanwhile, the error control programs have been designed, and the reliability of the simulated SCIs has been analysed through on-site tests, in order to improve the stability of data transmissions.

Doped nanoparticles were prepared from pyrene and phenanthrene using a facile reprecipitation method. The doped nanoparticles presented unique delayed fluorescent emissions of pyrene under the unprotected condition. The ratio of the intensity of delayed fluorescence (IDF) to that of phosphorescence (IP) is about 4:1, which almost keeps unchanged with the decrease of pyrene content at room temperature. The intensity of the delayed fluorescence emissions is dependent on the relative content of pyrene, as well as the aggregation degree of nanoparticles. The delayed emissions are contributed to efficient triplet-triplet energy transfer from phenanthrene (donor) to pyrene (acceptor). Steady fluorescence measurement have proved that the singlet-singlet energy transfer process was also existent dominated by the radiation energy transfer mechanism.

Based on the mechanism of vibrating stress relief and standard of JB/T5926-2005, vibrating stress relief method is used to eliminate residual stress of crane beam flange with butt weld. The welding residual stress of measured points is obtained by using blind-hole method. Experimental results show that the peak value of residual stress is reduced significantly, and the stress decline rate of residual stress is greater than the minimum requirement value of JB/T5926-2005. The effect of VSR method is remarkable.

During numerical simulation of welding process, the temperature field simulation is fundamental for simulating other issues of welding process, and establishing the heat source model is the most basic work for temperature filed simulation. Based on the analysis and induction of arc welding heat source model used in T-joint welding simulation, points out the existing problems and future development direction of heat source model for T-joint, provides a reference for further research and practical application.

In order to grasp the vibration characteristics of a novel High-Speed 4-HPS-HPH PMT(parallel machine tool), A vibration behaviors analysis method using virtual prototype simulation was put forward. By the united application of CAD, CAE and visual technologies, the rigid-flexible vibration model of 4-HPS-HPH PMT was constructed. Then the dynamic response of the tool tip, including vibration displacement, vibration velocity, vibration acceleration, and maximum dynamic stresses of driving limbs were realized. The simulation results show that the rigid-flexible vibration model proposed can indicate the vibration behaviors of parallel machine tool. This research provides necessary guidance for dynamic performance analysis, optimization design and control of this 4-HPS-HPH PMT.

A novel 5-Degree of Freedom PCMM (parallel coordinate measuring machine) was proposed, and its motion control system was designed. Compared with the other structural PCMMs, the structure feature of proposed PCMM was described. Then its motion control system was designed with the modularized and open architecture. The controlled scheme of hardware, which based on PC, PMAC motion control card and the precision measuring probe, was developed. The software of the motion control system was written by Visual Basic6.0 language. Finally, the process of motion control for 4-UPS-UPU PCMM was proposed. The new method above for design of motion control system is simple and effective, and may be applied to other parallel machine.

In order to obtain dynamic behaviors of a spatial rigid-flexible coupling system of PMT(parallel machine tool) without the construction of mathematical model, a new method for dynamic behaviors simulation, which integrates CAD, CAE and visual technologies, was presented. The solid model of PMT was built in SolidWorks and transmitted to ADAMS, the modal neutral file of flexible body including driving limbs and spherical joints were generated in ANSYS, and introduced into ADAMS, then the rigid-flexible coupling model of PMT was build. Based on the rigid-flexible coupling model, the dynamic behaviors, which includes displacements error output response, dynamic stress of driving limbs and natural frequency, were realized. The simulation results show that the rigid-flexible coupling model established can indicate the dynamic behaviors of PMT. The flexibility of driving limbs and spherical joints are demonstrated to have significant impact on dynamics characteristics of PMT. This research can provide the important theoretical base of the optimization design of dynamic parameters for PMT.

A mathematical model for getting the closed-form solution of main parameters of cylinder exhaust port is present, based on a few known parameters of variable-stroke engine (VSE). Considering lack of parameters in the initial stage of design, empirical formula is applied to solve the initial specific time-area value of exhaust port, and the initial port timing angle is solved by using logarithmic alignment method, thereby height and width of the exhaust port can be solved, then the precise specific time-area value and port timing angle are solved by using the coefficient calculation method and logarithmic alignment method respectively, so that the relative errors between initial and precise values of specific time-area value and port timing angle are defined as the relative errors of the mathematical model. Application examples show that the relative errors of the model is less than 3%.

In the last 10 years, nanomaterials based on small organic molecules have attracted increasing attention. Such materials have unique optical and electronic properties, which could lead to new applications in nanoscale devices. Zero-dimensional (0D) organic nanoparticles with amorphous structures have been widely studied; however, the systematic investigation of crystalline one-dimensional (1D) organic nanostructures has only emerged in recent years. Researchers have used inorganic 1D nanomaterials, such as wires, tubes, and belts, as building blocks in optoelectronic nanodevices. We expect that their organic counterparts will also play an important role in this field. Because organic nanomaterials are composed of molecular units with weaker intermolecular interactions, they allow for higher structural tunability, reactivity, and processability. In addition, organic materials usually possess higher luminescence efficiency and can be grown on almost any solid substrate. In this Account, we describe recent progress in our group toward the construction of organic 1D nanomaterials and studies of their unique optical and electronic properties. First, we introduce the techniques for synthesizing 1D organic nanostructures. Because this strategy is both facile and reliable, liquid phase synthesis is most commonly used. More importantly, this method allows researchers to produce composite materials, including core/sheath and uniformly doped structures, which allow to investigate the interactions between different components in the nanomaterials, including fluorescent resonance energy transfer and photoinduced electron transfer. Physical vapor deposition allows for the synthesis of organic 1D nanomaterials with high crystallinity. Nanomaterials produced with this method offer improved charge transport properties and better optoelectronic performance in areas including multicolor emission, tunable emission, optical waveguide, and lasing. Although inorganic nanomaterials have developed rapidly, our findings highlight the importance of organic compounds as components of novel 1D nanomaterials.

This article presents a comprehensive review of recent progress of research dedicated to low-dimensional nanomaterials constructed from functional low-molecular-weight organic compounds, whose optoelectronic properties are fundamentally different from those of their inorganic counterparts. After introducing the development of inorganic and organic macromolecular nanomaterials, we begin with a general review of the construction strategies for achieving both zero-dimensional (OD) and one-dimensional (ID) nanostructures from small organic functional molecules. We then provide an overview of the unique optoelectronic properties induced by molecular aggregation in the nanostructures. Special emphasis is put on the luminescent properties that are different from those of the corresponding bulk materials, such as aggregation-induced enhanced emission, fluorescence narrowing, multi-color emission, and tunable and switchable emissions from doped nanostructures. We conclude with a summary and our personal view of the direction of future development of organic opto-functional nanomaterials and devices.

During cooling of the ( R)-N-Fmoc-Octylglycine (Fmoc-OG)/cyclohexane solution, gelation is observed exclusively when ultrasound is used as an external stimulus, while deposit is obtained without sonication. The xerogel consists of entangled fibrous network made by interconnected nanofibers, while the deposit comprises large numbers of unbranched nanowires. It is found that the Fmoc-OG molecules form bilayer structures in both the deposit and the gel. However, the ratio ( R) between the Fmoc-OG molecules in a stable intramolecular H-bonding conformation and those in a metastable intermolecular H-bonding conformation can be tuned by the ultrasound, R (deposit)R (gel). The increased population of the intermolecular H-bonding Fmoc-OG molecules induced by the ultrasonication facilitates to the interconnection of nanofibers for the formation of the fibrous network, and therefore gelation. The alteration in the morphologies and properties of the obtained nanomaterials induced by the ultrasound wave demonstrates a potential method for smart controlling of the functions of nanomaterials from the molecular level.