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• Two new 3D Zn(II)/Co(II) CPs of sebacic acid and bbimb ligands are discribed. • CPs 1 and 2 display as 5-fold interpenetrating dia topology. • Both CPs exhibit selective sensing toward tryptophan and norfloxacin via turn-on and red shift effects. Two three-dimensional (3D) coordination polymers (CPs), namely {[M(seb)(bbimb)]·3H 2 O} n (M = Zn for 1 ; Co for 2), were obtained via hydrothermal method using sebacic acid (H 2 seb) mixed with 1,4-bis(benzoimidazol-1-yl)butane (bbimb). The structures of 1 and 2 both display as 3D frameworks with a 5-fold interpenetrating dia topology. CPs 1 and 2 both exhibit excellent luminescent properties and good water stability. Fluorescence sensing experiments demonstrate that 1 and 2 both can selectively detect tryptophan (Trp) and norfloxacin (Nor) in aqueous solution through turn-on and red-shift effect with remarkable anti-interference ability and low detection limits. The limits of detection (LOD) toward Trp-and Nor are 0.07 μ M, 0.08 μ M for 1 and 0.41 μ M, 0.11 μ M for 2. In addition, theoretical calculations and different detection methods were utilized to thoroughly investigate the potential sensing mechanisms for Trp-and Nor. Importantly, 1 and 2 represent two rare examples for sensing both Trp-and Nor via turn-on and red-shift effects. The fluoresence test films of 1 and 2 were prepared which can detect Trp-and Nor quickly with naked eye. [Display omitted] Two new 3D Zn(II)/Co(II) CPs of sebacic acid and bbimb ligands are discribed. CPs 1 and 2 display as 5-fold interpenetrating dia topology. Both CPs were confirmed to be luminescent sensors for detection of tryptophan (Trp) and norfloxacin (Nor) in aqueous solution through turn-on and red shift effects. [ABSTRACT FROM AUTHOR]

• Two new 3D Cd(II)/Co(II) MOFs based on binuclear clusters are described. • MOFs 1 and 2 display as 6-connected mab and bsn networks. • Both MOFs exhibit selective sensing toward Fe3+, Cr 2 O 7 2− and nitrobenzene. Two novel three-dimensional (3D) Cd(II)/Co(II) metal-organic frameworks (MOFs), [Cd 2 (seb) 2 (bbmb)(H 2 O) 2 ] n (1) and {[C o 2 (seb) 2 (bbmb) 2 (H 2 O)]·0·5H 2 O} n (2), were synthesized under hydrothermal conditions based on sebacic acid (H 2 seb) and 4,4′-Bis(benzimidazol-1-ylmethyl) biphenyl (bbmb) ligands. Their crystal structures were structurally characterized by single-crystal X-ray diffraction. MOFs 1 and 2 both show a 3D framework based on binuclear Cd 2 or Co 2 clusters, respectively. In 1, the Cd 2 clusters are linked by seb2- into a 2D corrugated layer. These layers are further connected by bbmb to generate a 3D structure with 6-connected (44·610·8) mab topology. In 2, the Co 2 clusters form a 1D chain through the bbmb ligands, the chains are linked by seb2− into a 3D framework with 6-connected (48·54·63) bsn topology. Fluorescence sensing experiments show that 1 and 2 have good ability for detection of Fe3+, Cr 2 O 7 2− and nitrobenzene (NB) with low detection limits as 5.83 μ M, 1.36 μ M and 2.70 × 10−7M for 1 and 6.19 μ M, 1.40 μ M and 2.90 × 10−7M for 2, respectively. Furthermore, the sensing mechanism was also investigated in detail by various detection means and theoretical calculations. Two new 3D Cd(II)/Co(II) MOFs of 4,4′-Bis(benzimidazol-1-ylmethyl) biphenyl and sebacic acid are described. MOFs 1 and 2 display as rarely reported 6-connected mab and bsn topologies based on the binuclear units. Both MOFs were confirmed to be luminescent sensors for Fe3+, Cr 2 O 7 2− and nitrobenzene. [Display omitted] [ABSTRACT FROM AUTHOR]

• Two new 3D Cd(II)/Co(II) MOFs based on binuclear clusters are described. • MOFs 1 and 2 display as 6-connected mab and bsn networks. • Both MOFs exhibit selective sensing toward Fe3+, Cr 2 O 7 2− and nitrobenzene. Two novel three-dimensional (3D) Cd(II)/Co(II) metal-organic frameworks (MOFs), [Cd 2 (seb) 2 (bbmb)(H 2 O) 2 ] n (1) and {[C o 2 (seb) 2 (bbmb) 2 (H 2 O)]·0·5H 2 O} n (2), were synthesized under hydrothermal conditions based on sebacic acid (H 2 seb) and 4,4′-Bis(benzimidazol-1-ylmethyl) biphenyl (bbmb) ligands. Their crystal structures were structurally characterized by single-crystal X-ray diffraction. MOFs 1 and 2 both show a 3D framework based on binuclear Cd 2 or Co 2 clusters, respectively. In 1, the Cd 2 clusters are linked by seb2- into a 2D corrugated layer. These layers are further connected by bbmb to generate a 3D structure with 6-connected (44·610·8) mab topology. In 2, the Co 2 clusters form a 1D chain through the bbmb ligands, the chains are linked by seb2− into a 3D framework with 6-connected (48·54·63) bsn topology. Fluorescence sensing experiments show that 1 and 2 have good ability for detection of Fe3+, Cr 2 O 7 2− and nitrobenzene (NB) with low detection limits as 5.83 μ M, 1.36 μ M and 2.70 × 10−7M for 1 and 6.19 μ M, 1.40 μ M and 2.90 × 10−7M for 2, respectively. Furthermore, the sensing mechanism was also investigated in detail by various detection means and theoretical calculations. Two new 3D Cd(II)/Co(II) MOFs of 4,4′-Bis(benzimidazol-1-ylmethyl) biphenyl and sebacic acid are described. MOFs 1 and 2 display as rarely reported 6-connected mab and bsn topologies based on the binuclear units. Both MOFs were confirmed to be luminescent sensors for Fe3+, Cr 2 O 7 2− and nitrobenzene. [Display omitted] [ABSTRACT FROM AUTHOR]

Two Cd(II) MOFs based on the 1,4-bis[(2-methyl-1H-imidazol-1-yl)-methyl]benzene (1,4-mbix) and succinate (Suc2−) or azelate (Aze2−) ligands have been hydrothermally synthesized, namely, {[Cd2(Suc)2(1,4-mbix)2]·5H2O}n (1) and [Cd(Aze)(1,4-mbix)]n (2). Both MOFs were structurally characterized by single-crystal X-ray diffraction. In MOF 1, the Cd(II) centers are connected by Suc2− and 1,4-mbix to generate a two-dimensional (2D) sql layer with (H2O)5 water cluster. Each 2D layer is further interlocked with two adjacent layers to form a 2D + 2D → 3D parallel polycatenated structure. In MOF 2, when the Suc2− was placed by Aze2−, the Cd(II) centers are connected by Aze2− and 1,4-mbix into a 2D sql layer but without any water molecules. And two 2D sql layers interpenetrate with each other to generate a twofold 2D + 2D → 2D sheet. MOFs 1 and 2 display photoluminescence at 343 nm (λex = 288 nm) and 298 nm (λex = 271 nm), respectively. Luminescent quenching experiments show that 1 and 2 have good ability for detection of Fe3+ in deionized water with low detection limits as 0.58 μM for 1 and 0.54 μM for 2, respectively. Two MOFs also can serve as luminescent sensors for Fe3+ in real tap water and river water. The luminescent quenching of 1 and 2 toward Fe3+ can be attributed to the competition among the absorption of Fe3+ with the excitation and emission of two MOFs. [ABSTRACT FROM AUTHOR]

• Yaw dynamics model of the electric tractor-plow unit is developed. • Learning-based double layer control method of yaw stability for electric tractor is proposed. • Comparative HIL experiments of three control methods are conducted under normal and harsh operating conditions. • The maximum yaw rate and sideslip angle tracking error is controlled within 0.096 rad/s and 0.044 rad. • The tracking accuracy is higher than the traditional control methods. Ensures yaw stability of electric tractors. Complex field environments and variable soil conditions make tractor plowing operations susceptible to maneuvering instability, especially challenging in yaw stability. A learning-based double layer control (LDLC) method of yaw stability for rear wheel independent drive electric tractor (ET) plowing operation is proposed in this paper in order to solve this problem. Firstly, a sliding window self-learning traction resistance predictor is proposed based on Gaussian process regression (GPR) theory to predict the future traction resistance of plowing operation. Then, a discrete nonlinear model predictive control (NMPC) supervisor yaw stability controller is designed based on the dynamics model of the plowing unit and the tire-soil model to solve for the additional yaw torque required to maintain the yaw stability of the tractor. Finally, considering the additional yaw moment and driver demand torque, the subordinate controller composed of a particle swarm optimization algorithm optimally allocates the driving torque of the two driving wheels. Hardware-in-the-loop test results show that the maximum mean tracking errors of yaw rate and sideslip angle are 0.002 rad/s and 0.01 rad for the LDLC controlled ET during straight line and continuous steering under normal plowing operation, the maximum mean tracking errors of yaw rate and sideslip angle are 0.007 rad/s and 0.012 rad for straight line and continuous steering plowing operations under harsh plowing operation. The tracking accuracy is significantly higher than traditional cascade PID and equal distribution control methods. The proposed LDLC method effectively ensures the yaw stability of the ET during straight line and continuous steering under normal and harsh plowing operation conditions. [ABSTRACT FROM AUTHOR]

• Three alkaline earth-based MOFs were synthesized under hydrothermal conditions. • Compounds 1-3 reveal structural diversity owing to different metal ions and organic ligands. • The luminescent properties of compounds 1 - 3 were studied in detail. The alkaline earth-based metal-organic frameworks (MOFs) have attracted more and more attention for their beautiful structure and environmental friendliness. In this work, three alkaline earth-based MOFs, namely [Ba(HL 1)] n (1), [Ca(HL 1)(H 2 O) 2 ] n (2), and [Ba(HL 2)] n (3) (H 3 L 1 = 1-(3-carboxyphenylmethyl)-1H-pyrazol-3,5-dicarboxylic acid and H 3 L 2 = 1-(4-carboxyphenylmethyl)-1H-pyrazol-3,5-dicarboxylic acid), were synthesized under hydrothermal conditions. Compounds 1-3 reveal structural diversity owing to different metal ions and organic ligands. Thermal and solvent stability were characterized by thermogravimetric analyses (TG) and powder X-ray diffraction (PXRD), respectively. The solid-state luminescent properties were also investigated. The result shows a clear correlation between emission bands and excitation wavelengths of compounds 1-3. Three new alkaline earth-based metal-organic frameworks with luminescent properties were synthesized and characterized. [Display omitted] [ABSTRACT FROM AUTHOR]

Two new three-dimensional (3D) Ni(II) coordination polymers (CPs), namely, {[Ni(L1)2(H2O)2]·(1,5-NDS)}n (1) and [Ni(L2)2(1,5-NDS)]n (2) have been hydrothermally synthesized based on 1,5-naphthalenedisulfonate (1,5-NDS) and two bis(benzimidazole) ligands (L1 = 1,4-bis(1H-benzimidazol-1-yl)butane, L2 = 1,2-bis(benzimidazol-1-ylmethyl)benzene). CP 1 presents a 3D framework with 4-connected 66dia topology. While CP 2 shows a 3D network with 6-connected (412.63) pcu topology. CPs 1 and 2 both exhibit excellent luminescent properties and good water stability. And luminescent sensing experiments reveal that both CPs can detect uric acid (UA) in aqueous solution through the luminescent quenching effect, and they also can detect tryptophan (Trp) in aqueous solution with red-shift and turn-on luminescent effect. The detection limits toward UA and Trp are 1.30 and 0.92 μM for 1, and those are 1.20 and 1.30 μM for 2, respectively. Furthermore, the luminescence sensing mechanisms were studied via PXRD patterns, UV–Vis spectra, lifetimes and theoretical calculations. The luminescence test films of 1 and 2 were also prepared for visual detection of UA and Trp. [ABSTRACT FROM AUTHOR]