Organic Electro-Optic Materials with High Electro-Optic Coefficients and Strong Stability.

The preparation of high-performance electro-optical materials is one of the key factors determining the application of optoelectronic communication technology such as 5G communication, radar detection, terahertz, and electro-optic modulators. Organic electro-optic materials have the advantage of a high electro-optic coefficient (~1000 pm/V) and could allow the utilization of photonic devices for the chip-scale integration of electronics and photonics, as compared to inorganic electro-optic materials. However, the application of organic nonlinear optical materials to commercial electro-optic modulators and other fields is also facing technical bottlenecks.

Fast-BEV: A Fast and Strong Bird's-Eye View Perception Baseline.

Recently, perception task based on Bird's-Eye View (BEV) representation has drawn more and more attention, and BEV representation is promising as the foundation for next-generation Autonomous Vehicle (AV) perception. However, most existing BEV solutions either require considerable resources to execute on-vehicle inference or suffer from modest performance. This paper proposes a simple yet effective framework, termed Fast-BEV, which is capable of performing faster BEV perception on the on-vehicle chips.

Fine-tuning of organic optical double-donor NLO chromophores with DA-supported functional groups.

New strategic chromophores with updated fine-tuning of previously reported BLD1 and BLD3 chromophores were designed. BLD1 and BLD3 have silicon functional groups on the donor unit, and the bridge has a good chance of self-assembling, so in the present study we fine-tuned the isolating groups to the bulky cyclic alkene to improve their dipole moment and organic electro-optic (OEO) properties as well. To demonstrate the impact of cyclic alkenes on the electron-donating groups in sensible NLO chromophore designs, a thorough analysis and comparison of the chromophore synthesis, UV-Vis calculations, solvatochromic behavior of the chromophore, DFT quantum mechanical calculations, thermal stabilities, and much lower dipole moments was conducted.

Highly Efficient and Stable Binary Cross-Linkable/ Self-Assembled Organic Nonlinear Optical Molecular Glasses.

The development of electro-optical materials with high chromophore loading levels that possess ultrahigh electro-optic coefficients and high long term alignment stability is a challenging topic. Anthracene-maleimide Diels-Alder (DA) reaction and π-π interaction of Anthracene-pentafluorobenzene and benzene-pentafluorobenzene are developed for making highly efficient binary cross-linkable/self-assembled dendritic chromophores FZL1-FZL4. A covalently or non-covalently cross-linked network is formed by DA reaction or π-π interaction after electric field poling orientation, which greatly improves the long-term alignment stability of the materials.

Electro-optic crosslinkable chromophores with ultrahigh electro-optic coefficients and long-term stability.

The development of organic electro-optic materials with ultrahigh electro-optic coefficients and high long-term alignment stability is the most challenging topic in this field. Next-generation crosslinkable nonlinear optical chromophore molecular glasses were developed to address this problem. A highly stable EO system including crosslinkable binary chromophores QLD1 and QLD2 or crosslinkable single chromophore QLD3 and multichromophore QLD4 with large hyperpolarizability was synthesized using tetrahydroquinoline as the donor.

Design of novel temperature-resistant and salt-tolerant acrylamide-based copolymers by aqueous dispersion polymerization.

Development of polymer-based flooding technology to improve oil recovery efficiency, water dispersion copolymerization of acrylamide, cationic monomer methacryloxyethyltrimethyl ammonium chloride (METAC), and anionic monomer acrylic acid (AA) were carried out in aqueous ammonium sulfate solution with polyvinyl pyrrolidone (PVP) as the stabilizer. The copolymers were characterized by H-NMR, FT-IR, TG, and SEM to confirm that they were prepared successfully and exhibited excellent salt-resistant property. Moreover, the effect of the aqueous solution of ammonium sulfate (AS) concentration, stabilizer concentration, and initiator concentration on the viscosity and size were systematically investigated.

ModuleNet: Knowledge-Inherited Neural Architecture Search.

Although neural the architecture search (NAS) can bring improvement to deep models, it always neglects precious knowledge of existing models. The computation and time costing property in NAS also means that we should not start from scratch to search, but make every attempt to reuse the existing knowledge. In this article, we discuss what kind of knowledge in a model can and should be used for a new architecture design.

Research on the mechanisms of polyacrylamide nanospheres with different size distributions in enhanced oil recovery.

Crosslinked polyacrylamide microspheres are widely used as in-depth flooding agents in petroleum development due to their unique properties of thickening, salt-resistance, high-temperature resistance, low cost, To solve the problem of their injections in heterogeneous reservoirs, polyacrylamide nanospheres were synthesized. However, mechanisms of polymer nanospheres in enhanced oil recovery were not investigated comprehensively. In this study, we synthesized polymer nanospheres with different size distributions and studied their mechanisms in enhancing the oil recovery.

A novel near-infrared-emitting aza-boron-dipyrromethene-based remarkable fluorescent probe for Hg in living cells.

A new near-infrared (NIR)-emitting aza-boron-dipyrromethene dye with two electron-donating amino groups at 1- and 7-positions has been prepared via several steps of reactions. This probe showed a NIR absorption at 748 nm with an obvious shoulder peak at 634 nm in CHCN/HO. Interestingly, a NIR fluorescence emission at 843 nm was observed with a large Stokes shift of 95 nm.

A near-infrared BODIPY-based fluorescent probe for ratiometric and discriminative detection of Hg and Cu ions in living cells.

A near-infrared distyryl boron dipyrromethene-based sensor bearing one bis(1,2,3-triazole)amino receptor has been synthesized. This probe selectively and quickly binds to Hg and Cu ions in CHCN/HO (5:1 v/v) and exhibits remarkably blue-shifted absorption and fluorescence bands due to the inhibition of the intramolecular charge transfer process. The fluorescence changes of this probe upon binding to Hg or Cu ion are totally different, undergoing a ratiometric fluorescence enhancement (for Hg) or a fluorescence quenching (for Cu) mechanism.

Diastereoselective synthesis of cyclopropanes bearing trifluoromethyl-substituted all-carbon quaternary centers from 2-trifluoromethyl-1,3-enynes beyond fluorine elimination.

Herein, a one-pot, two-step procedure for the diastereoselective synthesis of cyclopropanes bearing trifluoromethyl-substituted all-carbon quaternary centers has been described. Trifluoromethyl-activated 1,3-enynes undergo cyclopropanation reactions with sulfur ylides under mild reaction conditions without fluoride elimination, which affords the cis-isomer mainly. Interestingly, a sequential TBAF-mediated deprotection of the triisopropylsilyl group results in a diastereoenriched epimerization which gives rise to the trans-cyclopropanes as the sole isomers.

Nonlinear optical chromophores based on Dewar's rules: enhancement of electro-optic activity by introducing heteroatoms into the donor or bridge.

In this work, we investigated the enhancement of the electro-optic response by introducing electron-rich heteroatoms as additional donors into the donor or bridge of a conventional second-order nonlinear optical chromophore. A series of chromophores C2-C4 based on the same tricyanofuran acceptor (TCF) but with different heteroatoms in the alkylamino phenyl donor (C2 or C3) or thiophene bridge (C4) have been synthesized and systematically investigated. Density functional theory calculations suggested that chromophores C2-C4 had a smaller energy gap and larger first-order hyperpolarizability (β) than traditional chromophore C1 due to the additional heteroatoms.

The synthesis of new double-donor chromophores with excellent electro-optic activity by introducing modified bridges.

A series of chromophores y1–y3 based on the same bis(N,N-diethyl)aniline donor and the tricyanofuran acceptor (TCF) linked together via the modified thiophene π-conjugation with different isolated groups have been synthesized and systematically investigated in this paper. Density functional theory (DFT) was used to calculate the HOMO–LUMO energy gaps and first-order hyperpolarizability (β) of these chromophores. Besides, to determine the redox properties of these chromophores, cyclic voltammetry (CV) experiments were performed.

Synthesis and characterization of a novel second-order nonlinear optical chromophore based on a new julolidine donor.

A new chromophore HK containing the cis,cis-1,7-diethoxy-3-isopropyljulolidine group as a novel electron-donor, thiophene as a π-conjugated bridge and a tricyanofuran (TCF) acceptor has been synthesized and systematically investigated in this paper. Its corresponding chromophore FTC using 4-(diethyl amino)benzyl as the electron donor group was also prepared for comparison. This is the first time that the cis,cis-1,7-diethoxy-3-isopropyljulolidine group was introduced into NLO materials.