We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps betwe...We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps between states with different quantum numbers. The crossing points of some of the relative(composite) gaps have much weaker finite-size drifts than the normally used gaps defined only with respect to the ground state, thus allowing precise determination of quantum critical points even with small clusters. Our results support the picture of a spin liquid phase intervening between the well-known plaquette-singlet and antiferromagnetic ground states, with phase boundaries in almost perfect agreement with a recent density matrix renormalization group study, where much larger cylindrical lattices were used [J. Yang et al., Phys. Rev. B 105, L060409(2022)]. The method of using composite low-energy gaps to reduce scaling corrections has potentially broad applications in numerical studies of quantum critical phenomena.展开更多
A spectroscopic method to determine thickness on chromatic polarization interferometry. With of quartz wave plate is presented. The method is based the polarization-resolved transmission spectrum （PRTS） curve, the p...A spectroscopic method to determine thickness on chromatic polarization interferometry. With of quartz wave plate is presented. The method is based the polarization-resolved transmission spectrum （PRTS） curve, the phase retardation of quartz wave plate can be determined at a wide spectral range from 200 to 2000 nm obviously. Through accurate judgment of extreme points of PRTS curve at long-wave band, the physical thickness of quartz wave plates can be obtained exactly. We give a measuring example and the error analysis. It is found that the measuring precision of thickness is mainly determined by the spectral resolution of spectrometer.展开更多
Nitroxoline is a wide spectrum antibacterial and is one of the most important urinary antiseptics.The interaction between nitroxoline and human serum albumin(HSA)has been investigated systematically by fluorescence sp...Nitroxoline is a wide spectrum antibacterial and is one of the most important urinary antiseptics.The interaction between nitroxoline and human serum albumin(HSA)has been investigated systematically by fluorescence spectroscopy,synchronous fluorescence,three-dimensional fluorescence,CD spectroscopy and UV-Vis absorption spectroscopy.The results indicated that the quenching of HSA by nitroxoline was static.The corresponding thermodynamic parameters △H,△S and △G calculated according to van’t Hoff equation revealed that the intermolecular forces acting between nitroxoline and HSA were mainly hydrogen bonding and van der Waals forces.The conformational changes in the interaction were studied by synchronous fluorescence,CD spectroscopy and three-dimensional fluorescence spectra which showed changes in the microenvironment and conformation of HSA.展开更多
The basal levels of magnesium and copper in rat brain and flowering plum fruit dialysates, and the background concentration of calcium in pea dialysates have been determined with sensitive spectroscopic techniques inc...The basal levels of magnesium and copper in rat brain and flowering plum fruit dialysates, and the background concentration of calcium in pea dialysates have been determined with sensitive spectroscopic techniques including atomic absorption spectrometry and spectrophotometry based on amino G acid chlorophosphonazo. It is found that the magnesium level in flowering plum fruit dialysates is much lower than that in rat brain dialysates, indicating a considerable composition difference present between a plant dialysate and an animal one.展开更多
The absorption band center of visible and near infrared reflectance spectra is a key spectral parameter for lunar mineralogical studies, especially for the mafic minerals（olivine and pyroxene） of mare basalts, which...The absorption band center of visible and near infrared reflectance spectra is a key spectral parameter for lunar mineralogical studies, especially for the mafic minerals（olivine and pyroxene） of mare basalts, which have two obvious absorption bands at 1000 nm（Band I） and 2000 nm（Band II）. Removal of the continuum from spectra, which was developed by Clark and Roush and used to isolate the particular absorption feature, is necessary to estimate this parameter. The Moon Mineralogy Mapper（M3） data are widely used for lunar mineral identification. However, M3 data show a residual thermal effect, which interferes with the continuum removal, and systematic differences exist among optical data taken during different optical periods. This study investigated a suitable continuum removal method and compared the difference between two sets of M3 data taken during different optical periods, Optical Period 1B（OP1B）and Optical Period 2A（OP2A）. Two programs for continuum removal are reported in this paper. Generally,a program respectively constructs two straight lines across Band I and Band II to remove the continuum,which is recommended for locating band centers, because it can find the same Band I center with different right endpoints. The optimal right endpoint for continuum removal is mainly dominated by two optical period data at approximately 2480 and 2560 nm for OP1 B and OP2 A data, respectively. The band center values derived from OP1 B data are smaller than those derived from OP2 A data in Band I but larger in Band II, especially for the spectra using longer right endpoints（〉2600 nm）. This may be due to the spectral slopes of OP1 B data being steeper than those of OP2 A data in Band I but gentler in Band II. These results were applied to Mare Humorum and Mare Nubium, and the measurements were found to mainly vary from intermediate- to high-Ca pyroxene.展开更多
The Andromeda galaxy was observed by the Guoshoujing Telescope （formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope -- LAMOST）, during the 2009 commissioning phase. Due to the absence of sta...The Andromeda galaxy was observed by the Guoshoujing Telescope （formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope -- LAMOST）, during the 2009 commissioning phase. Due to the absence of standard stars for flux calibration, we use the photometric data of 15 intermediate bands in the Beijing-Arizona-Taipei-Connecticut （BATC） survey to calibrate the spectra. In to- tal, 59 spectra located in the bulge and disk of the galaxy are obtained. Kinematic and stellar population properties of the stellar content are derived with these spectra. We obtain the global velocity field and calculate corresponding rotation velocities out to about 7 kpc along the major axis. These rotation velocity measurements comple- ment those of the gas content, such as the H I and CO. The radial velocity dispersion shows that the stars in the bulge are more dynamically thermal and the disk is more rotationally-supported. The age distribution shows that the bulge was formed about 12 Gyr ago, the disk is relatively younger and the ages of some regions along the spi- ral arms can reach as young as about 1 Gyr. These young stellar populations have a relatively richer abundance and larger reddening. The overall average metallicity of the galaxy approximates the solar metallicity and a very weak abundance gradient is gained. The reddening map gives a picture of a dust-free bulge and a distinct dusty ring in the disk.展开更多
Unlike primary metabolites,secondary metabolites serve critical ecological functions,including plant protection,stress tolerance,and symbiosis.This review focuses on extracting,separating,and identifying the major cla...Unlike primary metabolites,secondary metabolites serve critical ecological functions,including plant protection,stress tolerance,and symbiosis.This review focuses on extracting,separating,and identifying the major classes of secondary metabolites,including alkaloids,terpenoids,phenolics,glycosides,saponins,and coumarins.It describes optimized methods regarding plant selection,extraction by solvents,and purification of the metabolites,highlighting the latest advancements in chromatographic and spectroscopic techniques.The review also describes some of the most important problems,such as the instability of the compounds or diversity of the structures,and discusses emerging technologies that solve these issues.Moreover,it examines the secondary roles of these metabolites in medicine,such as anticancer and antimicrobial drugs,sustainable agriculture biopesticides,and environmental ecology-also known as allelopathy and bioindicators.It combines traditional ethnobotanical approaches with contem-porary science,demonstrating the vital need to protect biodiversity in key ecosystems such as tropical rainforests,mountain regions,coral reefs,and arid zones as a foundation for anticipatory bio-discoveries.It organizes the methodological frameworks and outlines the steps needed to enhance the extraction of bioactive compounds from natural sources.展开更多
Soil quality monitoring is important in precision agriculture.This study aimed to examine the possibility of assessing the soil parameters in apple-growing regions using spectroscopic methods.A total of 111 soil sampl...Soil quality monitoring is important in precision agriculture.This study aimed to examine the possibility of assessing the soil parameters in apple-growing regions using spectroscopic methods.A total of 111 soil samples were collected from 11 typical sites of apple orchards,and the croplands surrounding them.Near-infrared(NIR) and mid-infrared(MIR) spectra,combined with partial least square regression,were used to predict the soil parameters,including organic matter(OM) content,pH,and the contents of As,Cu,Zn,Pb,and Cr.Organic matter and pH were closely correlated with As and the heavy metals.The NIR model showed a high prediction accuracy for the determination of OM,pH,and As,with correlation coefficients(r) of 0.89,0.89,and 0.90,respectively.The predictions of these three parameters by MIR showed reduced accuracy,with r values of 0.77,0.84,and 0.92,respectively.The heavy metals could also be measured by spectroscopy due to their correlation with organic matter.Both NIR and MIR had high correlation coefficients for the determination of Cu,Zn,and Cr,with standard errors of prediction of 2.95,10.48,and 9.49 mg kg-1 for NIR and 3.69,5.84,and 6.94 mg kg-1 for MIR,respectively.Pb content behaved differently from the other parameters.Both NIR and MIR underestimated Pb content,with r values of 0.67 and 0.56 and standard errors of prediction of 3.46 and 2.99,respectively.Cu and Zn had a higher correlation with OM and pH and were better predicted than Pb and Cr.Thus,NIR spectra could accurately predict several soil parameters,metallic and nonmetallic,simultaneously,and were more feasible than MIR in analyzing soil parameters in the study area.展开更多
Two new phenolic compounds were isolated from whole plant ofArtemisia sphaerocephala. The structures were elucidated on the basis of spectroscopic methods as 4-（1-hydroxylethyl）-phenol-l-O-β-D-glucopyranoside and 4...Two new phenolic compounds were isolated from whole plant ofArtemisia sphaerocephala. The structures were elucidated on the basis of spectroscopic methods as 4-（1-hydroxylethyl）-phenol-l-O-β-D-glucopyranoside and 4-O-acetophenone-β-D-gluco- pyranosyl-（1-3）-β-D-glucopyranoside.展开更多
Sky subtraction is a key technique in data reduction of multi-fiber spectra. Knowledge of characteristics related to the instrument is necessary to determine the method adopted in sky subtraction. In this study, we de...Sky subtraction is a key technique in data reduction of multi-fiber spectra. Knowledge of characteristics related to the instrument is necessary to determine the method adopted in sky subtraction. In this study, we describe the sky subtraction method designed for the Large sky Area Multi-Object fiber Spectroscopic Telescope （LAMOST） survey. The method has been integrated into the LAMOST 2D Pipeline v2.6 and applied to data from LAMOST DR3 and later. For LAMOST, calibration using sky emission lines is used to alleviate the position-dependent （and thus time-dependent） ,-~ 4% fiber throughput uncertainty and small wavelength instability （0.1/~） during observation. Sky subtraction using principal component analysis （PCA） further reduces 25% of the sky line residual from OH fines in the red part of LAMOST spectra after the master sky spectrum, which is derived from a B-spline fit of 20 sky fibers in each spectrograph. Using this approach, values are adjusted by a sky emission line and subtracted from each fiber. Further analysis shows that our wavelength calibration accuracy is about 4.5 km s-1, and the averages of residuals after sky subtraction are about 3% for sky emission lines and 3% for the continuum region. The relative sky subtraction residuals vary with moonlight background brightness, and can reach as low as 1.5% for regions that have sky emission lines during a dark night. Tests on F stars with both similar sky emission line strength and similar object continuum intensity show that the sky emission line residual of LAMOST is smaller than that of the SDSS survey.展开更多
This paper presents a relative flux calibration method for the Guoshoujing Telescope （LAMOST）, which may be applied to connect a blue spectrum to a red spectrum to build the whole spectrum across the total wavelengt...This paper presents a relative flux calibration method for the Guoshoujing Telescope （LAMOST）, which may be applied to connect a blue spectrum to a red spectrum to build the whole spectrum across the total wavelength range （3700 ～ 9000 A）. In each spectrograph, we estimate the effective temperatures of selected stars using a grid of spectral line indices in the blue spectral range and a comparison with stellar atmosphere models. For each spectrograph, stars of types A and F are selected as pseudo-standard stars, and the theoretical spectra are used to calibrate both the blue （3700 ～ 5900 A） and red spectrograph arms （5700 ～ 9000 A）. Then the spectral response function for these pseudo-standard stars could be used to correct the raw spectra provided by the other fibers of the spectrograph, after a fiber efficiency function has been derived from twilight flat-field exposures. A key problem in this method is the fitting of a pseudo stellar continuum, so we also give a detailed description of this step. The method is tested by comparing a small sample of LAMOST spectra calibrated in this way on stars also observed by the Sloan Digital Sky Survey. The result shows that the T eff estimation and relative flux calibration method are adequate.展开更多
For LAMOST, the largest sky survey program in China, the solution of the problem of automatic discrimination of stars from galaxies by spectra has shown that the results of the PSF test can be significantly refined. H...For LAMOST, the largest sky survey program in China, the solution of the problem of automatic discrimination of stars from galaxies by spectra has shown that the results of the PSF test can be significantly refined. However, the problem is made worse when the redshifts of galaxies are not available. We present a new automatic method of star/(normal) galaxy separation, which is based on Statistical Mixture Modeling with Radial Basis Function Neural Networks (SMM-RBFNN). This work is a continuation of our previous one, where active and non-active celestial objects were successfully segregated. By combining the method in this paper and the previous one, stars can now be effectively separated from galaxies and AGNs by their spectra-a major goal of LAMOST, and an indispensable step in any automatic spectrum classification system. In our work, the training set includes standard stellar spectra from Jacoby's spectrum library and simulated galaxy spectra of EO, SO, Sa, Sb types with redshift ranging from 0 to 1.2, and the test set of stellar spectra from Pickles' atlas and SDSS spectra of normal galaxies with SNR of 13. Experiments show that our SMM-RBFNN is more efficient in both the training and testing stages than the BPNN (back propagation neural networks), and more importantly, it can achieve a good classification accuracy of 99.22% and 96.52%, respectively for stars and normal galaxies.展开更多
The Large Sky-Area Multi-Object Spectroscopic Telescope (LAMOST) under construction by the National Astronomical Observatories will yield up to four thousand multi-fiber spectra of stars and galaxies per field. The pr...The Large Sky-Area Multi-Object Spectroscopic Telescope (LAMOST) under construction by the National Astronomical Observatories will yield up to four thousand multi-fiber spectra of stars and galaxies per field. The present series of papers describes the automated data-reduction pipeline currently being designed in order to cope with the anticipated flood of spectrographic data. In this preliminary paper, we present an automated method for estimating the continuum level, the positions of strong lines and the 4000 A break in galaxy spectra. In order to obtain detailed information on the continuum, we use a wavelet filter bank. After continuum fitting, our software searches for a 4000 A break and distinguishes between emission-line galaxies (ELGs) and non-ELGs according to whether the break is small or large. It then searches for strong lines and measures the intensities of emission lines and the equivalent widths of absorption lines. For non-ELGs, the absorption lines are identified automatically yielding redshift measurements.展开更多
A brief description of the NAO coude echelle spectrograph mounted on the 2.16 m telescope at Xinglong station is given. This echelle spectrograph is located at the coudé focus with a prism cross disperser. The ec...A brief description of the NAO coude echelle spectrograph mounted on the 2.16 m telescope at Xinglong station is given. This echelle spectrograph is located at the coudé focus with a prism cross disperser. The echelle image covers the spectral region from 330 to 1100 nm displayed in 80 spectral orders in one exposure through two light beams. With a slit height of 2mm, spectral orders are separated by 15 to 23 pixels in blue region and by 7 to 19 pixels in red region. Alternatively, two additional resolution modes corresponding to different focal length cameras with resolving power R 16000, 170 000 in the blue beam and R = 13000, 170 000 in the red beam could be provided by this spectrograph. The bias, dark, wavelength calibration, flat field and science exposure are described in details. The limiting magnitude for 1 hour exposure with an S/N ratio of 100 scales to V = 9.5 in the red path and to V = 7.2 in the blue path.展开更多
An automated classification technique for large size stellar surveys is proposed. It uses the extended Kalman filter as a feature selector and pre-classifier of the data, and the radial basis function neural networks ...An automated classification technique for large size stellar surveys is proposed. It uses the extended Kalman filter as a feature selector and pre-classifier of the data, and the radial basis function neural networks for the classification. Experiments with real data have shown that the correct classification rate can reach as high as 93%, which is quite satisfactory. When different system models are selected for the extended Kalman filter, the classification results are relatively stable. It is shown that for this particular case the result using extended Kalman filter is better than using principal component analysis.展开更多
Cholangiocellular cancer(CCC)is an oncological disease of the bile ducts characterized by a high mortality rate.To date,the use of standard methods for the diagnosis and treatment of CCC has not been able to reduce mo...Cholangiocellular cancer(CCC)is an oncological disease of the bile ducts characterized by a high mortality rate.To date,the use of standard methods for the diagnosis and treatment of CCC has not been able to reduce mortality from this disease.This work presents the results of fluorescence diagnostics(FD),which consists in using a modified optical fiber and photodynamic therapy(PDT)using a therapeutic laser instead of a low-intensity laser.This technique was tested on 43 patients in a clinical setting.The results obtained indicate a direct correlation between spectroscopic and video FD methods.Furthermore,a direct correlation was found between the photobleaching of a chlorin e6-based photosensitizer,with the commercial names of PhotoIon Radachlorin and Photoran and stricture regression.Our findings demonstrate the possibility of using a therapeutic laser with a wavelength of 660 nm for both diagnosis and treatment of bile ducts cancer,which results in a significant reduction of the operation time without decreasing its effectiveness.展开更多
A novel p-n heterojunction of anα-Fe_(2)O_(3)/NiO composite was prepared by precipitation and hydrothermal methods.The structure,morphology and composition of the composite were characterized by numerous spectroscopi...A novel p-n heterojunction of anα-Fe_(2)O_(3)/NiO composite was prepared by precipitation and hydrothermal methods.The structure,morphology and composition of the composite were characterized by numerous spectroscopic methods and its gas sensing properties for triethylamine(TEA)were also tested.The results showed that the composite(Fe/Ni=4:1 atomic ratio)exhibited a fast response approximately 4 times that ofα-Fe_(2)O_(3)with excellent selectivity,stability and linear response in the range from 5 to 25 ppm TEA at 140℃,which was due to the large specific surface area of the hierarchical structure and the formation of p-n heterojunctions at the interface of both the metal oxides.Therefore,the composite synthesized in this study is a promising sensing material for the detection of TEA and the work provides a new route to rationally design sensor structures for realizing the synergetic functions of metal oxide semiconductor interfaces.展开更多
Novel half-sandwich iridium(Ⅲ) complexes with aminomethyl(diphenyl)phosphine derived from fluoroquinolones (IrPCp,IrPSf,IrPLm,IrPNr) were studied as possible anticancer chemotherapeutics and showed higher potency tha...Novel half-sandwich iridium(Ⅲ) complexes with aminomethyl(diphenyl)phosphine derived from fluoroquinolones (IrPCp,IrPSf,IrPLm,IrPNr) were studied as possible anticancer chemotherapeutics and showed higher potency than other well-known metal-based agents i.e.,Pt(Ⅱ) drugs.All compounds were characterized by elemental analysis,selected spectroscopic methods (i.e.,absorption and fluorescence spectroscopy,NMR),ESI-MS spectrometry,X-ray diffraction,and electrochemical techniques.The studied complexes exhibited promising cytotoxicity in vitro with IC_(50) values significantly lower than that of the reference drug – cisplatin.The insight into the mode of action revealed the uniform distribution of the Ir(Ⅲ) complexes in both the nucleus and cytoplasm (Pearson’s co-localization coefficient of 0.63).Precise cytometric analysis provided clear evidence for the predominance of apoptosis in the induced cell death.The activation of caspase-3/7 along with the decrease of mitochondrial membrane potential also confirmed the apoptotic cell death.The investigated Ir(Ⅲ) complexes may induce changes in the cell cycle leading to G_(2)/M phase arrest.ROS generation as a plausible pathway responsible for the cytotoxicity was confirmed by determination of redox potentials enabling efficient ROS production.Furthermore,Pluronic P-123 micelles loaded with selected Ir(Ⅲ) complexes were proposed to overcome low solubility and to minimize serious systemic side effects by administering the complex in a controlled manner.The resulting nanoformulations (IrPCp_M,IrPNr_M) facilitated efficient drug accumulation for human lung adenocarcinoma and human prostate carcinoma (A549 and DU-145 cell lines),as demonstrated by confocal microscopy and ICP-MS analysis.In vitro cytotoxicity assays were also carried out within multicellular tumor spheroids and efficient anticancer action on these 3D assemblies was demonstrated.展开更多
Five bis(oxamato)palladate(Ⅱ)complexes of the formulae(n-Bu_(4)N)_(2)[Pd(4-Fpma)_(2)](1),(n-Bu_(4)N)_(2)[Pd(4-Clpma)_(2)](2),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)](3),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)]·H_(2)O(3a),(n-Bu_...Five bis(oxamato)palladate(Ⅱ)complexes of the formulae(n-Bu_(4)N)_(2)[Pd(4-Fpma)_(2)](1),(n-Bu_(4)N)_(2)[Pd(4-Clpma)_(2)](2),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)](3),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)]·H_(2)O(3a),(n-Bu_(4)N)_(2)[Pd(4-MeOpma)_(2)](4)and(n-Bu_(4)N)_(2)[Pd(4-Isopma)_(2)](5)(n-Bu_(4)N+=tetra-n-butylammonium,4-Fpma=N-4-fluorophenyloxamate,4-Clpma=N-4-chlorophenyloxamate,4-Brpma=N-4-bromophenyloxamate,4-MeOpma=N-4-methoxyphenyloxamate and 4-isopma=N-4-isopropylphenyloxamate)have been easily prepared and characterized by spectroscopic methods and the crystal structures of two of them(3a and 4)have been determined by single crystal X-ray diffraction.Each palladium(Ⅱ)ion in 3a and 4 is four-coordinate with two oxygen and two nitrogen atoms from two fully deprotonated oxamate ligands building a centrosymmetric square planar PdN_(2)O_(2)surrounding.The values of the Pd-N and Pd-O bond lengths vary in the ranges 2.034(3)-2.043(4)and 1.999(4)-2.013(3)Å,respectively.The reduced bite of the chelating oxamate ligands[81.3(2)-81.7(1)(3a)and 81.61(7)°(4)]is at the origin of the mean distortion of the ideal square environment.The catalytic role of compounds 1-5 as structurally well-defined precatalysts for the Heck-vinylation of a series of aryl iodide/bromide derivatives in n-Bu_(4)NBr as a benign nonaqueous ionic liquid(i.d.molten salt)has been examined and compared with some commercially available palladium(Ⅱ/0)complexes.From this study,it appears that the oxamate-containing precatalysts 1-5 are not just ecologically benign,but also highly efficient,easily recoverable and reusable at least eight times without any relevant loss of catalytic activity or leaching from the ionic liquid medium.展开更多
One dimensional metallophosphate coordination polymers{[M(dtbp)_(2)(azopy)(H_(2)O)_(2)]·(azopy)}_(x)(M=Mn(1);Co(2);Cu(3);Cd(4))have been synthesized from the reaction of a suitable metal precursor with di-tert-bu...One dimensional metallophosphate coordination polymers{[M(dtbp)_(2)(azopy)(H_(2)O)_(2)]·(azopy)}_(x)(M=Mn(1);Co(2);Cu(3);Cd(4))have been synthesized from the reaction of a suitable metal precursor with di-tert-butylphosphate(dtbp-H)in the presence of ditopic linker 4,4’-azobipyridine(azopy)in a 1:2:2 stoichiometric ratio.Isostructural compounds 1–4 have been characterized by analytical and spectroscopic methods and single crystal X-ray diffraction studies.Single crystal X-ray diffraction measurements further reveal that compounds 1–3(all C2/c)and 4(P1)are linear 1D coordination polymers.The uncoordinated 4,4’-azobipyridine in the lattice is responsible for the conversion of these 1D coordination polymers into 3D supramolecular assemblies through O–H⋯N hydrogen bonding interactions between coordinated water and N-centers of an azopy ligand.Similar reactions carried out using 1,2-bis(4-pyridyl)-ethylene(bpe)as the linker yielded compounds having the formula{[M(dtbp)_(2)(bpe)(H_(2)O)_(2)]·(bpe)}_(x)(M=Mn(5);Co(6);Cu(7);Ni(8)).Compounds 5–8 have been characterized by analytical and spectroscopic methods.Preliminary single crystal X-ray diffraction studies carried out on poorly diffracting crystals of 5 and 6 establish their isostructural nature to 1–4,also displaying a similar supramolecular aggregation behaviour.A longer ditopic N,N’-donor ligand,1,2-bis(pyridin-3-ylmethylene)hydrazine(bph),has been used in place of bpe/azoby to synthesize 1-dimensional coordination polymers[{M(bph)(H_(2)O)_(4)}{(dtbp)_(2)}](M=Ni(9)and M=Co(10))and[Cd(bph)_(3)(dtbp)_(2)]_(n)(11)which have completely different structural motifs when compared to 1–4.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 11874080 and 11734002)supported as a Simons Investigator by the Simons Foundation (Grant No. 511064)。
文摘We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps between states with different quantum numbers. The crossing points of some of the relative(composite) gaps have much weaker finite-size drifts than the normally used gaps defined only with respect to the ground state, thus allowing precise determination of quantum critical points even with small clusters. Our results support the picture of a spin liquid phase intervening between the well-known plaquette-singlet and antiferromagnetic ground states, with phase boundaries in almost perfect agreement with a recent density matrix renormalization group study, where much larger cylindrical lattices were used [J. Yang et al., Phys. Rev. B 105, L060409(2022)]. The method of using composite low-energy gaps to reduce scaling corrections has potentially broad applications in numerical studies of quantum critical phenomena.
基金This work was supported by the National Ba sic Research Program of China (973 Program) under Grant No. 2006CB806000.
文摘A spectroscopic method to determine thickness on chromatic polarization interferometry. With of quartz wave plate is presented. The method is based the polarization-resolved transmission spectrum （PRTS） curve, the phase retardation of quartz wave plate can be determined at a wide spectral range from 200 to 2000 nm obviously. Through accurate judgment of extreme points of PRTS curve at long-wave band, the physical thickness of quartz wave plates can be obtained exactly. We give a measuring example and the error analysis. It is found that the measuring precision of thickness is mainly determined by the spectral resolution of spectrometer.
基金financially supported by the National Science Fund for Distinguished Young Scholars of China(21225313)the National Natural Science Foundation of China(21303126)+2 种基金Program for Changjiang Scholars and Innovative Research Team in University(IRT1030)Foundation of Hubei Educational Committee(Q20132901)Youth Science Foundation of Huanggang Normal University(2013023903)
文摘Nitroxoline is a wide spectrum antibacterial and is one of the most important urinary antiseptics.The interaction between nitroxoline and human serum albumin(HSA)has been investigated systematically by fluorescence spectroscopy,synchronous fluorescence,three-dimensional fluorescence,CD spectroscopy and UV-Vis absorption spectroscopy.The results indicated that the quenching of HSA by nitroxoline was static.The corresponding thermodynamic parameters △H,△S and △G calculated according to van’t Hoff equation revealed that the intermolecular forces acting between nitroxoline and HSA were mainly hydrogen bonding and van der Waals forces.The conformational changes in the interaction were studied by synchronous fluorescence,CD spectroscopy and three-dimensional fluorescence spectra which showed changes in the microenvironment and conformation of HSA.
文摘The basal levels of magnesium and copper in rat brain and flowering plum fruit dialysates, and the background concentration of calcium in pea dialysates have been determined with sensitive spectroscopic techniques including atomic absorption spectrometry and spectrophotometry based on amino G acid chlorophosphonazo. It is found that the magnesium level in flowering plum fruit dialysates is much lower than that in rat brain dialysates, indicating a considerable composition difference present between a plant dialysate and an animal one.
基金supported by the Macao Science and Technology Development Fund(048/2012/A2,091/2013/A3 and 039/2013/A2)the National High Technology Research and Development Program of China(863 Program,2015AA123704)the National Natural Science Foundation of China(Nos.41172296 and 41422110)
文摘The absorption band center of visible and near infrared reflectance spectra is a key spectral parameter for lunar mineralogical studies, especially for the mafic minerals（olivine and pyroxene） of mare basalts, which have two obvious absorption bands at 1000 nm（Band I） and 2000 nm（Band II）. Removal of the continuum from spectra, which was developed by Clark and Roush and used to isolate the particular absorption feature, is necessary to estimate this parameter. The Moon Mineralogy Mapper（M3） data are widely used for lunar mineral identification. However, M3 data show a residual thermal effect, which interferes with the continuum removal, and systematic differences exist among optical data taken during different optical periods. This study investigated a suitable continuum removal method and compared the difference between two sets of M3 data taken during different optical periods, Optical Period 1B（OP1B）and Optical Period 2A（OP2A）. Two programs for continuum removal are reported in this paper. Generally,a program respectively constructs two straight lines across Band I and Band II to remove the continuum,which is recommended for locating band centers, because it can find the same Band I center with different right endpoints. The optimal right endpoint for continuum removal is mainly dominated by two optical period data at approximately 2480 and 2560 nm for OP1 B and OP2 A data, respectively. The band center values derived from OP1 B data are smaller than those derived from OP2 A data in Band I but larger in Band II, especially for the spectra using longer right endpoints（〉2600 nm）. This may be due to the spectral slopes of OP1 B data being steeper than those of OP2 A data in Band I but gentler in Band II. These results were applied to Mare Humorum and Mare Nubium, and the measurements were found to mainly vary from intermediate- to high-Ca pyroxene.
基金supported by the National Natural Science Foundation of China (GrantNos. 10873016,10633020,10603006,10803007,10903011,11003021 and 11073032)by the National Basic Research Program of China (973 Program Nos. 2007CB815403,2010CB833004 and 2009CB82480X)
文摘The Andromeda galaxy was observed by the Guoshoujing Telescope （formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope -- LAMOST）, during the 2009 commissioning phase. Due to the absence of standard stars for flux calibration, we use the photometric data of 15 intermediate bands in the Beijing-Arizona-Taipei-Connecticut （BATC） survey to calibrate the spectra. In to- tal, 59 spectra located in the bulge and disk of the galaxy are obtained. Kinematic and stellar population properties of the stellar content are derived with these spectra. We obtain the global velocity field and calculate corresponding rotation velocities out to about 7 kpc along the major axis. These rotation velocity measurements comple- ment those of the gas content, such as the H I and CO. The radial velocity dispersion shows that the stars in the bulge are more dynamically thermal and the disk is more rotationally-supported. The age distribution shows that the bulge was formed about 12 Gyr ago, the disk is relatively younger and the ages of some regions along the spi- ral arms can reach as young as about 1 Gyr. These young stellar populations have a relatively richer abundance and larger reddening. The overall average metallicity of the galaxy approximates the solar metallicity and a very weak abundance gradient is gained. The reddening map gives a picture of a dust-free bulge and a distinct dusty ring in the disk.
文摘Unlike primary metabolites,secondary metabolites serve critical ecological functions,including plant protection,stress tolerance,and symbiosis.This review focuses on extracting,separating,and identifying the major classes of secondary metabolites,including alkaloids,terpenoids,phenolics,glycosides,saponins,and coumarins.It describes optimized methods regarding plant selection,extraction by solvents,and purification of the metabolites,highlighting the latest advancements in chromatographic and spectroscopic techniques.The review also describes some of the most important problems,such as the instability of the compounds or diversity of the structures,and discusses emerging technologies that solve these issues.Moreover,it examines the secondary roles of these metabolites in medicine,such as anticancer and antimicrobial drugs,sustainable agriculture biopesticides,and environmental ecology-also known as allelopathy and bioindicators.It combines traditional ethnobotanical approaches with contem-porary science,demonstrating the vital need to protect biodiversity in key ecosystems such as tropical rainforests,mountain regions,coral reefs,and arid zones as a foundation for anticipatory bio-discoveries.It organizes the methodological frameworks and outlines the steps needed to enhance the extraction of bioactive compounds from natural sources.
基金Supported by the Major Science and Technology Program for Water Pollution Control and Treatment in China(No.2008ZX07425-001)
文摘Soil quality monitoring is important in precision agriculture.This study aimed to examine the possibility of assessing the soil parameters in apple-growing regions using spectroscopic methods.A total of 111 soil samples were collected from 11 typical sites of apple orchards,and the croplands surrounding them.Near-infrared(NIR) and mid-infrared(MIR) spectra,combined with partial least square regression,were used to predict the soil parameters,including organic matter(OM) content,pH,and the contents of As,Cu,Zn,Pb,and Cr.Organic matter and pH were closely correlated with As and the heavy metals.The NIR model showed a high prediction accuracy for the determination of OM,pH,and As,with correlation coefficients(r) of 0.89,0.89,and 0.90,respectively.The predictions of these three parameters by MIR showed reduced accuracy,with r values of 0.77,0.84,and 0.92,respectively.The heavy metals could also be measured by spectroscopy due to their correlation with organic matter.Both NIR and MIR had high correlation coefficients for the determination of Cu,Zn,and Cr,with standard errors of prediction of 2.95,10.48,and 9.49 mg kg-1 for NIR and 3.69,5.84,and 6.94 mg kg-1 for MIR,respectively.Pb content behaved differently from the other parameters.Both NIR and MIR underestimated Pb content,with r values of 0.67 and 0.56 and standard errors of prediction of 3.46 and 2.99,respectively.Cu and Zn had a higher correlation with OM and pH and were better predicted than Pb and Cr.Thus,NIR spectra could accurately predict several soil parameters,metallic and nonmetallic,simultaneously,and were more feasible than MIR in analyzing soil parameters in the study area.
文摘Two new phenolic compounds were isolated from whole plant ofArtemisia sphaerocephala. The structures were elucidated on the basis of spectroscopic methods as 4-（1-hydroxylethyl）-phenol-l-O-β-D-glucopyranoside and 4-O-acetophenone-β-D-gluco- pyranosyl-（1-3）-β-D-glucopyranoside.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant No.11503054)NSFC Key Program(Grant No.11333004)+6 种基金the National Key Basic Research Program of China(Program 973Grant No.2014CB845700)The Guo Shou Jing Telescope(the Large sky Area Multi-Object fiber Spectroscopic Telescope,LAMOST)is a National Major Scientific Project built by the Chinese Academy of Sciencesthe project has been provided by the National Development and Reform CommissionSDSS-Ⅲhas been provided by the Alfred P.Sloan Foundationthe Participating Institutions,the National Science Foundationthe U.S.Department of Energy Office of Science
文摘Sky subtraction is a key technique in data reduction of multi-fiber spectra. Knowledge of characteristics related to the instrument is necessary to determine the method adopted in sky subtraction. In this study, we describe the sky subtraction method designed for the Large sky Area Multi-Object fiber Spectroscopic Telescope （LAMOST） survey. The method has been integrated into the LAMOST 2D Pipeline v2.6 and applied to data from LAMOST DR3 and later. For LAMOST, calibration using sky emission lines is used to alleviate the position-dependent （and thus time-dependent） ,-~ 4% fiber throughput uncertainty and small wavelength instability （0.1/~） during observation. Sky subtraction using principal component analysis （PCA） further reduces 25% of the sky line residual from OH fines in the red part of LAMOST spectra after the master sky spectrum, which is derived from a B-spline fit of 20 sky fibers in each spectrograph. Using this approach, values are adjusted by a sky emission line and subtracted from each fiber. Further analysis shows that our wavelength calibration accuracy is about 4.5 km s-1, and the averages of residuals after sky subtraction are about 3% for sky emission lines and 3% for the continuum region. The relative sky subtraction residuals vary with moonlight background brightness, and can reach as low as 1.5% for regions that have sky emission lines during a dark night. Tests on F stars with both similar sky emission line strength and similar object continuum intensity show that the sky emission line residual of LAMOST is smaller than that of the SDSS survey.
基金funded by the National Natural Science Foundation of China (Grant No.10973021)
文摘This paper presents a relative flux calibration method for the Guoshoujing Telescope （LAMOST）, which may be applied to connect a blue spectrum to a red spectrum to build the whole spectrum across the total wavelength range （3700 ～ 9000 A）. In each spectrograph, we estimate the effective temperatures of selected stars using a grid of spectral line indices in the blue spectral range and a comparison with stellar atmosphere models. For each spectrograph, stars of types A and F are selected as pseudo-standard stars, and the theoretical spectra are used to calibrate both the blue （3700 ～ 5900 A） and red spectrograph arms （5700 ～ 9000 A）. Then the spectral response function for these pseudo-standard stars could be used to correct the raw spectra provided by the other fibers of the spectrograph, after a fiber efficiency function has been derived from twilight flat-field exposures. A key problem in this method is the fitting of a pseudo stellar continuum, so we also give a detailed description of this step. The method is tested by comparing a small sample of LAMOST spectra calibrated in this way on stars also observed by the Sloan Digital Sky Survey. The result shows that the T eff estimation and relative flux calibration method are adequate.
基金Supported by "863" National High Technology R&D program.
文摘For LAMOST, the largest sky survey program in China, the solution of the problem of automatic discrimination of stars from galaxies by spectra has shown that the results of the PSF test can be significantly refined. However, the problem is made worse when the redshifts of galaxies are not available. We present a new automatic method of star/(normal) galaxy separation, which is based on Statistical Mixture Modeling with Radial Basis Function Neural Networks (SMM-RBFNN). This work is a continuation of our previous one, where active and non-active celestial objects were successfully segregated. By combining the method in this paper and the previous one, stars can now be effectively separated from galaxies and AGNs by their spectra-a major goal of LAMOST, and an indispensable step in any automatic spectrum classification system. In our work, the training set includes standard stellar spectra from Jacoby's spectrum library and simulated galaxy spectra of EO, SO, Sa, Sb types with redshift ranging from 0 to 1.2, and the test set of stellar spectra from Pickles' atlas and SDSS spectra of normal galaxies with SNR of 13. Experiments show that our SMM-RBFNN is more efficient in both the training and testing stages than the BPNN (back propagation neural networks), and more importantly, it can achieve a good classification accuracy of 99.22% and 96.52%, respectively for stars and normal galaxies.
文摘The Large Sky-Area Multi-Object Spectroscopic Telescope (LAMOST) under construction by the National Astronomical Observatories will yield up to four thousand multi-fiber spectra of stars and galaxies per field. The present series of papers describes the automated data-reduction pipeline currently being designed in order to cope with the anticipated flood of spectrographic data. In this preliminary paper, we present an automated method for estimating the continuum level, the positions of strong lines and the 4000 A break in galaxy spectra. In order to obtain detailed information on the continuum, we use a wavelet filter bank. After continuum fitting, our software searches for a 4000 A break and distinguishes between emission-line galaxies (ELGs) and non-ELGs according to whether the break is small or large. It then searches for strong lines and measures the intensities of emission lines and the equivalent widths of absorption lines. For non-ELGs, the absorption lines are identified automatically yielding redshift measurements.
基金This wor is supported by NKBRSF G1999075406the National Natural Science FOundation of China under gran No. 19725312 and No.
文摘A brief description of the NAO coude echelle spectrograph mounted on the 2.16 m telescope at Xinglong station is given. This echelle spectrograph is located at the coudé focus with a prism cross disperser. The echelle image covers the spectral region from 330 to 1100 nm displayed in 80 spectral orders in one exposure through two light beams. With a slit height of 2mm, spectral orders are separated by 15 to 23 pixels in blue region and by 7 to 19 pixels in red region. Alternatively, two additional resolution modes corresponding to different focal length cameras with resolving power R 16000, 170 000 in the blue beam and R = 13000, 170 000 in the red beam could be provided by this spectrograph. The bias, dark, wavelength calibration, flat field and science exposure are described in details. The limiting magnitude for 1 hour exposure with an S/N ratio of 100 scales to V = 9.5 in the red path and to V = 7.2 in the blue path.
基金Supported by the National Natural Science Foundation of China (Project No. 60275002) The National High Technology Research and Development Program of China (863 Program, Project No.2003AA133060).
文摘An automated classification technique for large size stellar surveys is proposed. It uses the extended Kalman filter as a feature selector and pre-classifier of the data, and the radial basis function neural networks for the classification. Experiments with real data have shown that the correct classification rate can reach as high as 93%, which is quite satisfactory. When different system models are selected for the extended Kalman filter, the classification results are relatively stable. It is shown that for this particular case the result using extended Kalman filter is better than using principal component analysis.
基金This work was funded by RFBR according to the research project(Nos.17-00-00162 and 17-00-00159).
文摘Cholangiocellular cancer(CCC)is an oncological disease of the bile ducts characterized by a high mortality rate.To date,the use of standard methods for the diagnosis and treatment of CCC has not been able to reduce mortality from this disease.This work presents the results of fluorescence diagnostics(FD),which consists in using a modified optical fiber and photodynamic therapy(PDT)using a therapeutic laser instead of a low-intensity laser.This technique was tested on 43 patients in a clinical setting.The results obtained indicate a direct correlation between spectroscopic and video FD methods.Furthermore,a direct correlation was found between the photobleaching of a chlorin e6-based photosensitizer,with the commercial names of PhotoIon Radachlorin and Photoran and stricture regression.Our findings demonstrate the possibility of using a therapeutic laser with a wavelength of 660 nm for both diagnosis and treatment of bile ducts cancer,which results in a significant reduction of the operation time without decreasing its effectiveness.
基金supported by the National Natural Science Foundation of China(No.51973099,21627813 and 51772015)National Key R&D Program of China(2016YFB0301600 and 2016YFC0207100)+1 种基金Taishan Scholar Program of Shandong Province(No.tsqn201812055)Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology,School of Chemistry and Chemical Engineering,Guangxi University,Nanning 530004,China.
文摘A novel p-n heterojunction of anα-Fe_(2)O_(3)/NiO composite was prepared by precipitation and hydrothermal methods.The structure,morphology and composition of the composite were characterized by numerous spectroscopic methods and its gas sensing properties for triethylamine(TEA)were also tested.The results showed that the composite(Fe/Ni=4:1 atomic ratio)exhibited a fast response approximately 4 times that ofα-Fe_(2)O_(3)with excellent selectivity,stability and linear response in the range from 5 to 25 ppm TEA at 140℃,which was due to the large specific surface area of the hierarchical structure and the formation of p-n heterojunctions at the interface of both the metal oxides.Therefore,the composite synthesized in this study is a promising sensing material for the detection of TEA and the work provides a new route to rationally design sensor structures for realizing the synergetic functions of metal oxide semiconductor interfaces.
基金support of the Polish National Science Centre(Grant 2016/23/D/ST5/00269).
文摘Novel half-sandwich iridium(Ⅲ) complexes with aminomethyl(diphenyl)phosphine derived from fluoroquinolones (IrPCp,IrPSf,IrPLm,IrPNr) were studied as possible anticancer chemotherapeutics and showed higher potency than other well-known metal-based agents i.e.,Pt(Ⅱ) drugs.All compounds were characterized by elemental analysis,selected spectroscopic methods (i.e.,absorption and fluorescence spectroscopy,NMR),ESI-MS spectrometry,X-ray diffraction,and electrochemical techniques.The studied complexes exhibited promising cytotoxicity in vitro with IC_(50) values significantly lower than that of the reference drug – cisplatin.The insight into the mode of action revealed the uniform distribution of the Ir(Ⅲ) complexes in both the nucleus and cytoplasm (Pearson’s co-localization coefficient of 0.63).Precise cytometric analysis provided clear evidence for the predominance of apoptosis in the induced cell death.The activation of caspase-3/7 along with the decrease of mitochondrial membrane potential also confirmed the apoptotic cell death.The investigated Ir(Ⅲ) complexes may induce changes in the cell cycle leading to G_(2)/M phase arrest.ROS generation as a plausible pathway responsible for the cytotoxicity was confirmed by determination of redox potentials enabling efficient ROS production.Furthermore,Pluronic P-123 micelles loaded with selected Ir(Ⅲ) complexes were proposed to overcome low solubility and to minimize serious systemic side effects by administering the complex in a controlled manner.The resulting nanoformulations (IrPCp_M,IrPNr_M) facilitated efficient drug accumulation for human lung adenocarcinoma and human prostate carcinoma (A549 and DU-145 cell lines),as demonstrated by confocal microscopy and ICP-MS analysis.In vitro cytotoxicity assays were also carried out within multicellular tumor spheroids and efficient anticancer action on these 3D assemblies was demonstrated.
基金Financial support from the Spanish Ministerio de Ciencia e Innovación(MCIIN)through Project CTQ2013-448449the Generalitat Valenciana(PROMETEOII/2014/070 and ISIC/2012/002)+4 种基金the Italian Ministero dell’Istruzione dell’Universitàe della Ricerca Scientifica(MiUR)the European Community’s Seventh Framework Program(FP72007-2013)through the MATERIA Project(PONa3_00370)is acknowledgedthe MCIIN for a predoctoral FPU grantthe European Commission,FSE(Fondo Sociale Europeo)Calabria Region for a post-doctoral fellowship.
文摘Five bis(oxamato)palladate(Ⅱ)complexes of the formulae(n-Bu_(4)N)_(2)[Pd(4-Fpma)_(2)](1),(n-Bu_(4)N)_(2)[Pd(4-Clpma)_(2)](2),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)](3),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)]·H_(2)O(3a),(n-Bu_(4)N)_(2)[Pd(4-MeOpma)_(2)](4)and(n-Bu_(4)N)_(2)[Pd(4-Isopma)_(2)](5)(n-Bu_(4)N+=tetra-n-butylammonium,4-Fpma=N-4-fluorophenyloxamate,4-Clpma=N-4-chlorophenyloxamate,4-Brpma=N-4-bromophenyloxamate,4-MeOpma=N-4-methoxyphenyloxamate and 4-isopma=N-4-isopropylphenyloxamate)have been easily prepared and characterized by spectroscopic methods and the crystal structures of two of them(3a and 4)have been determined by single crystal X-ray diffraction.Each palladium(Ⅱ)ion in 3a and 4 is four-coordinate with two oxygen and two nitrogen atoms from two fully deprotonated oxamate ligands building a centrosymmetric square planar PdN_(2)O_(2)surrounding.The values of the Pd-N and Pd-O bond lengths vary in the ranges 2.034(3)-2.043(4)and 1.999(4)-2.013(3)Å,respectively.The reduced bite of the chelating oxamate ligands[81.3(2)-81.7(1)(3a)and 81.61(7)°(4)]is at the origin of the mean distortion of the ideal square environment.The catalytic role of compounds 1-5 as structurally well-defined precatalysts for the Heck-vinylation of a series of aryl iodide/bromide derivatives in n-Bu_(4)NBr as a benign nonaqueous ionic liquid(i.d.molten salt)has been examined and compared with some commercially available palladium(Ⅱ/0)complexes.From this study,it appears that the oxamate-containing precatalysts 1-5 are not just ecologically benign,but also highly efficient,easily recoverable and reusable at least eight times without any relevant loss of catalytic activity or leaching from the ionic liquid medium.
文摘One dimensional metallophosphate coordination polymers{[M(dtbp)_(2)(azopy)(H_(2)O)_(2)]·(azopy)}_(x)(M=Mn(1);Co(2);Cu(3);Cd(4))have been synthesized from the reaction of a suitable metal precursor with di-tert-butylphosphate(dtbp-H)in the presence of ditopic linker 4,4’-azobipyridine(azopy)in a 1:2:2 stoichiometric ratio.Isostructural compounds 1–4 have been characterized by analytical and spectroscopic methods and single crystal X-ray diffraction studies.Single crystal X-ray diffraction measurements further reveal that compounds 1–3(all C2/c)and 4(P1)are linear 1D coordination polymers.The uncoordinated 4,4’-azobipyridine in the lattice is responsible for the conversion of these 1D coordination polymers into 3D supramolecular assemblies through O–H⋯N hydrogen bonding interactions between coordinated water and N-centers of an azopy ligand.Similar reactions carried out using 1,2-bis(4-pyridyl)-ethylene(bpe)as the linker yielded compounds having the formula{[M(dtbp)_(2)(bpe)(H_(2)O)_(2)]·(bpe)}_(x)(M=Mn(5);Co(6);Cu(7);Ni(8)).Compounds 5–8 have been characterized by analytical and spectroscopic methods.Preliminary single crystal X-ray diffraction studies carried out on poorly diffracting crystals of 5 and 6 establish their isostructural nature to 1–4,also displaying a similar supramolecular aggregation behaviour.A longer ditopic N,N’-donor ligand,1,2-bis(pyridin-3-ylmethylene)hydrazine(bph),has been used in place of bpe/azoby to synthesize 1-dimensional coordination polymers[{M(bph)(H_(2)O)_(4)}{(dtbp)_(2)}](M=Ni(9)and M=Co(10))and[Cd(bph)_(3)(dtbp)_(2)]_(n)(11)which have completely different structural motifs when compared to 1–4.
