bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystal Structure and Magnetic Properties of a Vanadium (IV) Pyrophosphate: Rb2V3P4O17
Authors: Lii Kwang‐Hwa , Wang Yau‐Pey , Chneg Chih‐Yi , Wang Sue‐Lein , Ku Huan‐Chiu 
Published: June 2015

AbstractThe crystal structure of Rb2V3P4O17 has been determined from single‐crystal X‐ray diffraction data. Rb2V3P4O17 crystallizes in the orthorhombic space group Pnma (No. 62) with a = 17.502(7), b = 7.292(2), c = 11.399(6) Å3, V = 1455(1) Å3, Z=4, R=0.0295, RW = 0.0320 for 1129 unique reflections with I > 2.5 σ(I). The structure contains intersecting tunnels where the Rb+ cations are located. The framework can be described as consisting of V2O10 units formed from one VO5 square pyramid and one VO6 octahedron sharing a corner, and infinite chains of corner‐shared VO6 octahedra, which are linked in three dimensions by pyrophosphate groups. The structural formula is Rb2(VO)3(P2O7)2. A single‐phase product can be obtained by heating appropriate amounts of Rb4V2O7, VO2, V, and P2O5 in an evacuated fused silica tube at 950°C. Powder magnetic susceptibility data confirm the presence of V4+ (d1) ions without magnetic ordering down to 3 K.
Videomicroscopic Observation of Nonequilibrium Growth Patterns of Crystals
Authors: Tsai Chung‐Hsien , Hsu Tze‐Jeng , Mou Chung‐Yuan 
Published: June 2015

AbstractWe have developed a video‐microscopic computer imaging system for observing meso‐scale nonequilibrium physicochemical structures. Chargcd‐coupled device (CCD) in optical detection, and computer‐enhancement of digitized image, have greatly improved the resolution, sensitivity, and dynamical range of this technique. We apply this system to the observation of various complex crystallization patterns from Suberic acid melts and Camphene condensation. These patterns are of the scale one to 100 micrometers. They are resulted from nonlinear dynamical instabilities of a growing crystal fronts. The following patterns are observed: dendrites, destabilization of flat surface, cellular solidification, tip‐splitting, and dense branches. A computer simulation based on diffusion‐limited aggregates (DLA) model is performed to show this instability. The DLA model with surface tension effect is able to result in fractal‐like, dendrite, and needle‐like growth pattern.
An Efficient Synthesis of (±)‐α‐Spirovetivene and Related Compounds
Authors: Zee Sheng‐Hsu , Chou Shan‐Yen 
Published: June 2015

AbstractA process for the synthesis of (±)‐α‐spirovetivene starting from I‐oxo–2‐carbethoxy‐6, 10‐dimethyl spiro[4.5]dec‐6‐ene(I)1 is described. The oxo group of I was reduced by the process of Coates2, and the resulting spiro ester (III) and spiro alcohol (IV) were transformed to (±)‐α‐spirovetivene by the process of Uijttewaal3 and by conventional methods.
Ab Initio and MNDO Calculations Comparison with the VSEPR Model
Authors: Shalabi Ahmed 
Published: June 2015

AbstractAb initio and MNDO calculations of VSEPR model were carried out on CH2, CH2+, CH2−, SiH2, SiH2+ and SiH2−. Comparisons between the second row carbon and its third row silicon analogue as unshared electron pair contributors are considered. The repulsion effects as well as the volume requirement of the unshared electron pair on several structural and energetic properties arc investigated.
Solvent Extraction of Vanadium with α‐Benzoin Oxime
Authors: Li Chin‐Hou , Chen Shou‐Nan , Gi Hung‐Jang 
Published: June 2015

AbstractThe solvent extraction of vanadium by a chloroform solution of α‐benzoin oxime was investigated. The most favorable condition for the extraction has been found in the pH rang of 1.8 to 3.0 in sulfate or chloride buffer solutions, but with better extraction efficiency when sulfate was used. A solution of 2×10−2 M α‐benzoin oxime in chloroform was used, and 1×10−4 to 2×10−2 M vanadium(V) was extracted favorably in about 89% yield by a single extraction, and in about 97% yield by a double extraction. The effects of shaking time, concentration of α‐benzoin oxime, and diverse ions have also been investigated. Vanadium(V) can be readily extracted without interference in the presence of copper(II), aluminum(III), iron(III), silver(I), zirconium(IV), and chromium(III).
A Free Radical Hyperfine Coupling Constants Calculation Using the S‐P Indo‐Mo Method
Authors: Chen Cheng , Ding Guang Rung 
Published: June 2015

AbstractWe apply our newly developed s‐p separation model INDO‐MO theory to the open shell problem of organic free radicals and radical ions. The linear correlation analysis between spin densities and the related hyperfine coupling constants is preformed. To show the generality of this method for various elements, we select different sets of free radicals which contain 1H, 13C, 14N, 17O and 19F for our MO calculation. We chose the appropriate values of βα2P and βπ2P (the separated bond parameters calculated by the method described in our previous publication) and we also calibrated new geometrical parameters (bond distances and bond angles). With these new sets of parameters, many types of calculations were performed for comparison. We also compare our results with the corresponding results of the INDO‐MO method of Pople et al. In all cases involving 1H, 13C, 14N, 17O and 19F our MO method gives better results. This evidence also proves that our “s‐p separation model INDO‐MO method” is a reasonable and useful MO method.
Laser Spectroscopy on the MgH A2Π ‐ X2Σ+ Band System
Authors: Hsiao Tein‐Chai , Luo Yeung‐Long , Lin King‐Chuen , Luh Wei‐Tzou 
Published: June 2015

AbstractThe A2Π ‐ X2Σ+ electronic transition of MgH has been studied by the laser excitation spectroscopy. Some new transitions have been observed for the first time. Rotational parameters of the X and A state have been derived and compared with other experimental values.
Kinetics of Hydrolysis of Some Bifunctional Schiff Bases
Authors: Mahmoud M.R. , El‐Nady A.M. , Adam F.A. , El‐Taher M.A. 
Published: June 2015

AbstractKinetics of hydrolysis of some bifunctional Schiff bases, bis(x‐benzylidenes)‐o‐phenylenediamine, have been investigated in aqueous media containing 0.1 mole fraction of ethanol under base and acid conditions. Under base conditions the rate determining step is the hydroxide ion attack on the protonated substrate while under weak acid conditions the attack of water rather than hydroxide ion on the protonated substrate becomes the predominant reaction pathway. The bifunctional Schiff base molecular structure‐base or acid hydrolysis reactivity relationship has been examined and discussed. Effect of medium (water content and nature of organic solvents) has been investigated and it is deduced that specific solute‐solvent interactions, namely the proton‐solvent, play a vital role on such hydrolysis reaction.
Preparation of a Heavy Metal‐Removed Seawater
Authors: Pai Su‐Cheng , Huang Shang‐Da , Hung Chin‐Chang 
Published: June 2015

AbstractA purification procedure is described for preparing a heavy metal‐removed blank seawater without altering its major compositions and pH. Coastal seawater is treated sequentially by passing through a charcoal column, shaking with a dense slurry of ferric hydroxide at pH 8, and passing the surpernatant through a Chelex‐100 chelating ion‐exchange column. Experimental data show that this process efficiently removes Cd, Co, Cu, Cr(III), Fe, Mn, Ni, Pb, V and Zn from natural seawater at the spiking concentrations of 10 and 100 ppb levels.
Enhanced Kinetic Isotope Effect of the Phosphate‐Catalyzed Proton Exchange in N,N'‐Dimethylurea
Authors: Wang Wei‐Hsien , Cheng Ching‐Chih , Lee Ming‐Chao 
Published: June 2015

AbstractThe concerted mechanism of phosphate‐catalyzed proton exchange in N,N'‐dimethylurea has been studied. Kinetic data were measured using the technigue of NMR line‐shape analysis. A significant kinetic isotope effect was observed for the concerted proton transfer in N,N'‐dimethylurea and is attributed to the tunnelling effect.
Studies on Vilsmeier‐Haack Reaction: Application to 3‐Methyl‐1‐Phenyl‐4‐Acetyl(Iminoacetyl)‐2‐Pyrazolin‐5‐One
Authors: Awad Ibrahim M.A. , Hassan Khairy M. 
Published: June 2015

Abstract3‐Methyl‐l‐phenyl‐4‐acetyl(iminoacetyl)‐2‐pyrazolinones (1a,b) underwent diformylation reaction with Vilsmeier reagent to give the aminoacrolein derivatives (2a,b). The behaviour of (2a,b) towards piperidinc, morpholine, piperazine, hydroxylamine, hydrazine and phenylhydrazine has been investigated and screened in vitro for their antibacterial activities.
Reactions of 6‐Amino‐5‐Cyano‐3‐Methyl‐1,4‐Diphenyl‐1H 4H‐Pyrano[2,3‐C]Pyrazole and its Methanimidate
Authors: Younes Mansour I. , Atta Aly H. , Metwally S.A.M. 
Published: June 2015

AbstractReaction of 6‐amino‐5‐cyano‐3‐methyl‐1,4‐diphenyl‐ 1H,4H‐pyrano[2,3‐c]pyrazole 1 with triethyl orthoformate in acetic anhydride gave its methanimidate 2, which reacts with primary aliphatic and aromatic amines to give 4,6‐dihydro‐3‐methyl‐1,4‐diphenyl‐6‐ (alkyl)pyrazolo[4′,3′:5,6]pyrano[2,3‐d]pyrimidine‐5(lH)‐ imine 3 and the starting compound 1, respectively. Treatment of 1 with o‐aminophenol gave 5‐(2‐benzoxalyl)‐ 1,4‐dihydro‐3‐methyl‐1,4‐diphenylpyrano[2,3‐c]pyrazol‐ 6‐amine 9.
Comparison between Theoretical and Experimental Deformation Density of 1,3,5,7‐Tetra‐t‐Butyl‐S‐Indacene
Authors: Wang Yu , Wang Chih‐Chieh 
Published: June 2015

Abstract1,3,5,7‐Tetra‐t‐butyl‐s‐indacene is a twelve‐membered fused‐ring compound; the stabilization of the compound by bulky t‐butyl groups is discussed. The distribution of bonding electron density is depicted in terms of deformation density using the experimental X‐X method, a multipole expansion model and a calculation according to the extended Hückel molecular orbital method (EHMO). The molecules crystallize according to the space group P21/n with cell parameters a = 9.700(3), b = 11.746(3), c = 10.858(2)Å, β = 107.67(2)°, Z=2 at 100K. The molecule has a center of inversion( ) and belongs to the symmetry point group Ci. The packing of two unique t‐butyl groups in the asymmetric unit appears significantly different. However, the map of deformation density in the plane of the ring shows pseudo D2h symmetry. The accumulation of density at the midpoint of the bonds is observed as expected. The theoretical deformation densities agree with the experimental ones. Analyses of the molecular‐orbital wavefunctions provide a good illustration of the aromatic π‐electron system. A theoretical study of a series of substituents (‐H, ‐ CH3, ‐t‐butyl ) on s‐indacene illustrates the stabilization effect of the t‐butyl group on the 12‐π‐electron ring system.
Primary Structure of the Pike Eel (Muranesox Cinereus) Growth Hormone
Authors: Liu Chen‐Sheng , Wang Yi‐Chi , Chen Jin‐Mei , Chang Chen‐Hsien , Chen Shun‐Wen , Huang Fore‐Lien , Lo Tung‐Bin 
Published: June 2015

AbstractBy means of alkaline extraction, gel filtration and two kinds of high‐performance liquid chromatography, a growth hormone from pike eel pituitary was purified and its primary structure determined. There are two forms of growth hormone, one of which has three more amino acids at the N‐terminal. The same situation arises in the Japanese eel. With invariant four half‐cystines, it is composed of 190 amino acids; similar to the growth hormone of the Japanese eel, it differs only in six amino‐acid residues.
Application of Pulsed Field Gradients in High‐Resolution NMR Spectroscopy
Authors: Doddrell David M. 
Published: June 2015

AbstractIn this paper the applicability of pulsed field gradients in high‐resolution NMR spectroscopy are considered. Applications include solvent suppression, spectral editing of one‐ and two‐dimensional (2D) NMR spectra and the induction of quadrature detection in the w1, direction of many 2D experiments. The applications are analysed using simple product operator algebra. Particular attention is directed to discussing the experimental requirements of this technology in order that high‐resolution NMR conditions are maintained throughout the experiment.
Silicon‐29 NMR Study of Alkali‐Exchanged NaY Zeolites
Authors: Chern Jer‐Young , Chao Kuei‐Jung 
Published: June 2015

AbstractHigh‐resolution solid‐state 29Si NMR has been applied to the study of partially exchanged Li, K, and Cs NaY zeolites. The order of the 29Si chemical shifts of dehydrated samples is Li, Na‐Y < Na‐Y < K, Na‐Y. The correlation between the 29Si chemical shift and the Li or K loading on Li, Na‐Y or K, Na‐Y was rationalized in terms of the interaction between the framework and the cations inside the small cages. Because of the restrictive migration of large Cs+ ions from the supercages to the small cages, the 29Si chemical shift of Cs, Na‐Y was found to be similar to that of Na‐Y.
Improved Synthesis of 9‐ and 10‐Methylbenz[a] Anthracenes
Authors: Lai Ching‐Cheng , Own Zang‐Yuan , Unruh Leonard E. , Chou Ming W. 
Published: June 2015

AbstractThe synthesis of 9‐ and 10‐methylbenz[a]anthracenes by improved methods are described. These new procedures are simple and convenient, and provide the title compounds in good yields and high purity.
Regiochemistry of Nucleophilic Addition to Cyclohexadienyl‐Iron Complexes Having Sterically Demanding Substituents
Authors: Ong Chi Wi , Liou Wen Tzong 
Published: June 2015

AbstractThe reactions of sterically hindered tricarbonyl(cyclohexadienylium)‐iron with nucleophilic reagents have been studied. The influence of the 4‐alkoxyl substituents versus the bulkiness of the 1‐alkyl substituents on the regioselectivity of nucleophilic addition was investigated. With sodium borohydride as nucleophile, substantial addition at the C‐1 dienylium terminus was observed to take place via the more crowded endo face to give the more stable exo product. We here report the importance of steric hindrance to the approach of nucleophiles versus product stability during nucleophilic addition to the dienylium complexes.
Carbon‐13 NMR Studies of 3‐Aryl‐4‐(5‐aryl‐Δ 2‐1,2,4‐oxadiazolin‐3‐yl)sydnones and 3‐Aryl‐4‐(5‐aryl‐1,2,4‐oxadiazol‐3‐yl)sydnones
Authors: Ma Sun , Huang Chin‐Lin , Yeh Mou‐Yung 
Published: June 2015

AbstractThe 13C NMR spectra of twelve 3‐aryl‐4‐(5‐aryl‐Δ2‐l,2,4‐oxadiazolin‐3‐yl)sydnones and twelve 3‐aryl‐4‐(5‐aryl‐l,2,4‐oxadiazol‐3‐yl)sydnones have been measured and assigned by means of proton‐noise decoupling and DEPT‐experiments. The coupling constants were determined by means of gated decoupling, and NOE effects were observed by comparison of proton‐decoupled and inverse‐gated decoupled spectra. Differences shown by the oxadiazoline and the oxadiazole rings and the substitution effects are discussed.
Synthesis and Photochemistry of syn‐ and anti‐9,10‐Epoxy‐1, 4‐dihydro‐1,4‐ethanonaphthalene‐2,3‐diones
Authors: Liao Chun‐Chen , Hseu Tzong‐Hsiung , Lin Ho‐Shen , Tang Chia‐Pin , Ueng Yih‐Gang , Wang Jinn‐Lung , Wann Gwo‐Huei , Wu Kuan‐Syh 
Published: June 2015

AbstractThe title epoxydiketones were prepared stereoselectively, direct epoxidation of 3a‐c with MCPBA produced syn isomers la‐c whereas epoxidation of 4a‐d followed by saponification of the spirolactone rings gave anti isomers 2a‐c. The stereochemistry of 1a and 2a was established by X‐ray diffraction, whereas that of the remaining epoxydiketones was determined from the correlation of visible, 1H, and 13C NMR spectral data; the differences between spectra of the corresponding syn and anti isomers are explained in terms of through‐space interaction and steric effects. Photolysis of syn isomers 1a‐c afforded the corresponding naphthalenes 8a‐c in almost quantitative yields; in contrast, irradiation of anti isomers 2a‐c gave complicated mixtures. The quantum yield of disappearance of 1a was 52 times that of 2a. Reaction mechanisms are proposed to account for the product formation. The differences in the photochemical behavior of the title syn and anti isomers are rationalized in terms of stereoelectronic effects of the epoxy rings in the syn isomers.
On the Discovery of Direct Ortho‐Magnesiation
Authors: Eaton Philip E. , Xiong Yusheng , Lee Chih‐Hung 
Published: June 2015

AbstractMetalation of 2,4‐dicyanocubanecarboxamide (4) with lithium tetramethylpiperidide (LiTMP) followed by quenching with CO2 is non‐regioselective and results in carboxylation at the 3 (→ 5) and 6 (→ 6 ) positions. However, when the reaction was repeated with LiTMP pre‐treated with more than 0.5 equivalent of MgBr2, only 6 was produced. This was shown to occur by direct, regiospecific ortho‐magnesiation by the bases BrMgTMP and MgTMP2. This initial observation of ortho‐magnesiation has opened the way to wide application of this new methodology, a valuable and useful complement to ortho‐lithiation.
Kinetics of the Decomposition of Ferrocenium Ion and Its Derivatives
Authors: Huang Wen Hong , Jwo Jing‐Jer 
Published: June 2015

AbstractThe first‐order kinetics of the decomposition of ferrocenium ion (Fc+) and its substitution derivatives have been studied in aqueous sulfuric acid and in the presence of excess Ce(IV) ion. The observed first‐order rate constant (kobs) is expressed as kobs = kd for the acyl‐substituted ferrocenium ions and kobs = kd+ kox[Ce(IV)]o for the unsubstituted and alkyl‐substituted ferrocenium ions. Electron‐donating alkyl substituents stabilize the ferrocenium ion whereas electron‐withdrawing acyl substituents make it less stable. The order of relative stability toward decomposition is 1,1′‐dimethyl Fc+ ≥ butyl Fc+ > 1,1‐dimethylpropyl Fc+ > Fc+ > > formyl Fc+ > acetyl Fc+ > > benzoyl Fc+. A mechanism to interpret the kinetics is also given.
Free‐Radical Reaction of 2‐Vinylcyclopropane‐1,1‐dicarboxylate with Alkynes
Authors: Chuang Che‐Ping , Ngoi Tak Ho Johnny 
Published: June 2015

AbstractA free‐radical reaction of dimethyl 2‐vinylcyclopropane‐1,1‐dicarboxylate with electron rich alkynes giving cyclopentene systems is described. This reaction can be achieved with p‐toluenesulfonyl chloride and phenyldisulfide as radical precursors.
Structural Studies of Transition Metal Compounds
Authors: Saito Yoshihiko 
Published: June 2015

AbstractA historical overview will be given on the structural studies on transition metal compounds and their interaction with other fields of coordination chemistry. About three decades have passed away since the structure and absolute configuration of tris(ethylenediamine)cobalt(III) complex ion were determined. At present accumulation of the structural data for isomers has enabled us to understand structural principles of chelate complexes in considerable detail. The energy minimization calculations can predict the detailed geometries of the complexes. Differences in thermodynamic properties between different conformers are well reproduced.Aspherical distribution of 3d electrons in transition metal complexes was detected for the first time in crystals of [Co(NH3)6][Co(CN)6] in 1973. Such an accurate electron density study provides important information on the d electrons placed in a ligand field. The high‐spin and low‐spin states can be distinguished unequivocally. In spite of a very small valence/total electron ratio, the asphericity of 4d and 5d electrons in a ligand field can be detected.The crystal structures of a series of dimeric copper(II) carboxylate adducts of the general formula [Cu(RCOO)2L]2 have been determined or redetermined as accurately as possible. The temperature dependent magnetic susceptibility of these crystals indicated that the isolated pairs of Cu(II) ions interact strongly through exchange forces. Molecular orbital calculations revealed that the electron population in the carbon atom of the bridging OCO group plays an important role in determining the strength of the spin superexchange interaction.In the crystals of some cobaloxime complexes, racemization of chiral groups bonded to Co proceeds on X‐ray exposure without degradation of crystallinity. Several intermediate stages could be determined by X‐ray analysis. Various reaction pathways were recognized and the reaction rate could be correlated with the atomic arrangement in the crystal.
Does He2 Exist?
Authors: Ogilvie J. F. , Wang Frank Ye Howe 
Published: June 2015

AbstractFor the electronic ground state X 1Σ+g, the potential‐energy function of He2 reported by Aziz et al. has been transformed into the form V(z), containing only eight parameters, which is more suitable for the investigation of the existence of states of discrete energy. We found no evidence that a bound vibration‐rotational state of the stable diatomic molecule 3He2 or 4He2, even if rotating, can exist in the electronic ground state.
Effects of Ring Size on Spectral Properties of Copper(II)‐Diaminodiamide Complexes in Aqueous Solution
Authors: Len Ching‐Hohn , Chung Chung‐Sun 
Published: June 2015

AbstractThe electronic absorption spectra of aqueous solutions containing copper(II) ion and N, N′‐bis(carbamoylmethyl)trimethylenediamine(L‐1, 3, 1) at 25.0 ± 0.1°C and 0.10 mol L−1 NaClO4, were measured as a function of pH. The absorption maxima and the molar absorptivities of [Cu(L‐l, 3, l)]2+, [Cu(H.1L‐1, 3, 1)]+, and [Cu(H‐2L‐l, 3, l)] were calculated from these spectra. A comparison of the spectral parameters of these complexes with those of the copper(lI)‐diaminodiamide complexes containing 6, 5, 6‐and 6, 6, 6‐membered ring systems indicates that the chelate ring size has significant effects on these spectral parameters.
Effect of Positions of Methyl Substituents in the Complexation Kinetics of Macrocyclic Tetraamines with Copper(II) in Strongly Basic Aqueous Media
Authors: Hu Mon‐Ai , Chung Chung‐Sun 
Published: June 2015

AbstractThe complexation kinetics of the reaction of copper(II) with isomeric tetraamine macrocyclic ligands, C‐rac‐5, 7, 7, 12, 12, 14‐hexamethyl‐l, 4, 8, 11‐tetraazacyclotetradecane (tet c), C‐meso‐5, 7, 7, 12, 12, 14‐hexamethyl‐l, 4, 8, 11‐tetraazacyclotetradecane (tet d), and C‐meso‐5, 5, 7, 12, 12, 14‐hexamethyl‐1, 4, 8, 11‐tetraazacyclotetradecane (tet a) in strongly basic aqueous media have been examined at 25.0 ± 0.1°C by means of the stopped‐flow technique. The variation in the values of the resulting rate constants indicates that the positions of the methyl substituents play a significant role in these reactions. These reactions exhibit associative character and second‐bond formation is proposed as the rate‐determining step.
Steady‐State Kinetics of Aminopeptidase Catalysis: A Stopped‐Flow Radiationless Energy Transfer Study
Authors: Lin Wann‐Yin , Lin Gang‐Hong 
Published: June 2015

AbstractStopped‐flow radiationless energy transfer experiments have been carried out to investigate the hydrolysis of some dansyl peptide substrates (S) catalyzed by aminopeptidase (E). RET between enzyme tryptophanyl residues and the dansyl group in the substrate allowed direct observation and quantitation of the enzyme‐substrate (ES) complexes. Analysis of the stopped‐flow RET traces gives kcat = 1.32 s−1 and KM = 47 μM for Leu‐Ala‐NH(CH2)2NH‐Dns (Leu‐Ala‐DED) and kcat = 4.80 s−1 and KM = 196 μM for Leu‐Gly‐NH(CH2)2NH‐Dns (Leu‐Gly‐DED). The activation energies of the enzymatic reactions were determined from the Arrhenius plots to be 57 and 38 kJ mol−1 for Leu‐Ala‐DED and Leu‐Gly‐DED, respectively. The kinetic results indicate that the enzyme binds Leu‐Ala‐DED more tightly than Leu‐Gly‐DED as revealed by a small value of KM. That this enzyme catalyzes the turnover of Leu‐Gly‐DED more efficiently than Leu‐Ala‐DED is reflected in a large value of kcat and a small activation energy. The RET signals during the hydrolysis of Leu‐Val‐NH(CH2)2NH‐Dns were extremely weak probably because of the inefficient energy transfer in the ES complex or the retention of the product in the enzyme after completion of the reaction. Aminopeptidase was inactive towards the dansyl compounds of the single amino acid studied. This fact may be due to an unfavorable conformation of these compounds in the ES complexes (small kcat) or a weak binding of the substrates to the enzyme (large KM) or both.