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An important indicator of the rangeland health, associated with land degradation, is the ability of semi-natural rangelands to provide forage of sufficient quality for livestock production. In Qilian Mountains (Gansu Province, NW China) biomass production and forage quality are dependent on the seasonality of precipitation and temperature; most of the precipitation falls during summer season, when sheep, goats and yaks graze mountain rangelands. To sustain the rangelands and to improve the management strategies, the assessment of the forage quality should be implemented. The purpose of this research was to study the response of biomass, forage quality and macronutrient content different levels of grazing intensity in Qilian rangelands. We sampled aboveground biomass in the growing seasons in 2012 and 2013 within spring/autumn or summer grazing regimes in two altitudinal zones below and above 3000 m a.s.l. (montane-subalpine and subalpine-alpine respectively). In order to estimate forage quality, biomass was sampled in 1 m × 1 m plots, assigned to the center of 10 ×10 m sites, from which we collected different indicator parameters of rangeland health. Mineral and fiber content of forage biomass was estimated under different levels of grazing intensity with regard to the growing period. It was found that an increase in grazing intensity led to a decrease in dry matter weight. No linearity was observed in the relationship between nutritive value and grazing intensity. The highest fiber content (59.20 %) was found in plots mostly disturbed by grazing. The highest protein (16.30 %) and the lowest fiber (51.30 %) contents were associated with slightly grazing intensity. Concentrations of the mineral elements, such as Zn, P, K and S varied significantly and showed maximum values under low grazing intensity.

To ensure the secure and stable operation of lithium-ion batteries, the state of health (SOH) and the remaining useful life (RUL) are the critical state parameters of lithium-ion batteries, which need to be estimated precisely. A joint SOH and RUL estimation approach based on an improved Particle Swarm Optimization Extreme Learning Machine (PSO-ELM) is proposed in this paper. The approach adopts Pearson coefficients to screen multivariate information of the discharge process as health indicators and uses them as inputs to enable accurate estimation of SOH and RUL prediction of lithium-ion batteries on the basis of the PSO-ELM model. The validity of the model is demonstrated by the NASA lithium-ion battery data set: the maximum root mean square error (RMSE) of the SOH estimation of the tested battery is 0.0033, the maximum RMSE of its RUL prediction is 0.0082, and the maximum absolute error of RUL prediction is one cycle number. In comparison with the prediction results of the traditional extreme learning machine, the optimized model proposed in this paper estimates the SOH of lithium-ion batteries and RUL with relatively high accuracy.

The estimation of power battery state of charge and the selection of an effective equivalent model have always been the focus and difficulty of current research. This article has improved and optimized the traditional Thevenin model, and the performance of the Li-ion-ion battery is tested through Hybrid Pulse Power Characterization (HPPC) experiments. The off-line curve fitting identification method is used to identify the relevant parameters in the model to obtain the intrinsic relationship with the state of charge (SOC). An equivalent circuit model is established on the simulation platform to compare and verify actual data. The error of the verification result is controlled within 3.05%, which proves the effectiveness of the improved Thevenin model. On the basis that the relevant parameters of the equivalent model have been identified, the recursive principle of the extended Kalman filter algorithm (EKF) is studied, and the algorithm is applied to the Li-ion battery SOC estimation to obtain an accurate state estimation of the Li-ion battery. The algorithm is simulated and verified under working conditions, and the verification showed that its accuracy reached more than 98.376%, which ensured the reliability of the battery during use.

Here, a facile solvothermal method coupled with an annealing strategy is developed to synthesize Fe3O4/carbon (Fe3O4@C) magnetic composite microstructures with different morphologies, including flower-like, hollow spheres and egg-like. Owing to the unique multi-porous and hollow structure, the as-prepared hierarchical Fe3O4@C hollow microspheres composite exhibit appealing performance as an absorbent of Cr(VI) ions in aqueous solution, delivering a high capacity of ca.197.2mg/g. Furthermore, the magnetic Fe3O4 ‘‘core’’ in composite hierarchical microstructures makes them easy to separate from aqueous systems by magnetic separation, the layer of carbon effectively prevents agglomerations of magnetic nanoparticles and expands their range of applications. The excellent Cr(VI) ions adsorbent activities of the Fe3O4@C magnetic composite microstructures would have a potential adsorbing material application in environmental purification.

Aegilops longissima (2n = 2x = 14, SlSl), has extensive allelic variations of glutenin subunits that are considered as useful gene sources for wheat quality improvement. The Chinese Spring 1Sl(1B) chromosome substitution line CS-1Sl(1B) showed superior dough properties and breadmaking quality due to the introgression of novel glutenin subunits encoded by 1Sl genome. In this study, we identified one novel 1Sl-encoded low molecular weight glutenin B-subunit 1SlLMW-s from CS-1Sl(1B). Its complete encoding sequences were isolated and designated as 1SlLMW-s with 960 bp encoding 318 amino acid residues. Molecular characterization demonstrated that the deduced 1SlLMW-s subunit had a rather large and regular repeated sequence domain, including a high proportion of glutamine residues (about 44%) in the repeats (consensus sequence PPFSQQQQ). A total of 31 SNPs were detected at different positions of encoding sequences. The secondary structure prediction revealed higher β-strand and α-helix content present in 1SlLMW-s. Phylogenetic tree revealed that 1SlLMW-s had close evolutionary relationship with other s-type low molecular weight glutenin subunit (LMW-GSs) genes from different Triticum and Aegilops genomes, which was divergent from LMW-s type gene subfamily at 3.92–5.23 million years ago (MYA). LMW-GSs play a key role in improving breadmaking quality. Abundant expression and specific structural features could contribute to superior gluten quality, including larger and more regular repeated domain, higher proportion of glutamine residues and higher β-strand and α-helix content. This could facilitate the formation of stronger dough structure and superior breadmaking quality. Our work demonstrated that Sl genome had potential glutenin gene resources, and particularly 1SlLMW-s gene could be useful for wheat quality improvement.

The aim of this study was attempted to investigate both the glycation kinetics and protein secondary conformational changes of human serum albumin (HSA) after the reaction with ribose. The browning and fluorescence determinations as well as Fourier transform infrared (FTIR) microspectroscopy with a curve-fitting technique were applied. Various concentrations of ribose were incubated over a 12-week period at 37 ± 0.5 oC under dark conditions. The results clearly shows that the glycation occurred in HSA-ribose reaction mixtures was markedly increased with the amount of ribose used and incubation time, leading to marked alterations of protein conformation of HSA after FTIR determination. In addition, the browning intensity of reaction solutions were colored from light to deep brown, as determined by optical observation. The increase in fluorescence intensity from HSA–ribose mixtures seemed to occur more quickly than browning, suggesting that the fluorescence products were produced earlier on in the process than compounds causing browning. Moreover, the predominant α-helical composition of HSA decreased with an increase in ribose concentration and incubation time, whereas total β-structure and random coil composition increased, as determined by curve-fitted FTIR microspectroscopy analysis. We also found that the peak intensity ratios at 1044 cm−1/1542 cm−1 markedly decreased prior to 4 weeks of incubation, then almost plateaued, implying that the consumption of ribose in the glycation reaction might have been accelerated over the first 4 weeks of incubation, and gradually decreased. This study first evidences that two unique IR peaks at 1710 cm−1 [carbonyl groups of irreversible products produced by the reaction and deposition of advanced glycation end products (AGEs)] and 1621 cm−1 (aggregated HSA molecules) were clearly observed from the curve-fitted FTIR spectra of HSA-ribose mixtures over the course of incubation time. This study clearly suggests that FTIR spectroscopic curve-fitting technique may be easily used to allow determining the marked changes in the secondary conformational structure and protein aggregation of HSA during ribosylation as well as the production of AGEs.

Leishmania spp. are able to survive and proliferate inside mammals' mononuclear phagocytes, causing Leishmaniasis. Previous studies have noted that the regulation of apoptosis in host cells by these parasites may contribute to their ability to evade the immune system. However, current results remain unclear about whether the parasites can promote or delay the apoptotic process in host cells, because the regulatory effect of Leishmania was assumed to be strain-, species- and even infection time-dependent. The aim of this study was to investigate whether the Sichuan isolates of Chinese Leishmania (SC10H2) can alter the process of intrinsic apoptosis induced by cycloheximide in different types of macrophage cell lines and to determine in which steps of the signaling pathway the parasites were involved. Human THP-1 and mouse RAW264.7 macrophages were infected by SC10H2 promastigotes followed by cycloheximide stimulation to assess the alteration of intrinsic apoptosis in these cells. The results indicated that SC10H2 infection of human THP-1 macrophages could promote the initiation of intrinsic apoptosis, but completely opposite results were found in mouse RAW264.7 macrophages. Nevertheless, the expression of Bcl-2 and the DNA fragmentation rates were not altered by SC10H2 infection in the cell lines used in the experiments. This study suggests that SC10H2 promastigote infection is able to promote and delay the transduction of early apoptotic signals induced by cycloheximide in THP-1 and RAW264.7 macrophages, revealing that the regulation of intrinsic apoptosis in host cells by SC10H2 in vitro occurs in a host cell-dependent manner. The data from this study might play a significant role in further understanding the relationship between Leishmania and different host cells.

Genetic transformation is an important technique for functional genomics study and genetic improvement of plants. Until now, Agrobacterium-mediated transformation methods using cotyledon as explants has been the major approach for cucumber, and its frequency has been up to 23%. For example, significantly enhancement of the transformation efficiency of this plant species was achieved from the cotyledon explants of the cultivar Poinsett 76 infected by Agrobacterium strains EHA105 with efficient positive selection system in lots of experiments. This review is to summarize some key factors influencing cucumber regeneration and genetic transformation, including target genes, selection systems and the ways of transgene introduction, and then to put forward some strategies for the increasing of cucumber transformation efficiency. In the future, it is high possible for cucumber to be potential bioreactor to produce vaccine and biomaterials for human beings.

Metal-organic frameworks Mn(HCOO)3[(CH3)2NH2] (DMMnF) materials are prepared by hydrothermal growth technique. We analyze its crystal structure by X-ray Diffraction (XRD), chemical composition by infrared spectroscopy(IR).The results show that DMMnF belong to trigonal system, space group is R3-CH, the lattice constant is a=8.3330 (17) A, c= 22.947 (11) A, γ=120°,V=1379.09 (10) A3, Z=6.The morphology of DMMnF crystal is rhombohedral, and the large flat surface is (012). IR spectra shows that organic functional groups of DMMnF are dimethylamino and formate.

The aim of the work was to analysis effects of biogas residue continuous application on soil fertility improvment. The results showed that biogas residue addtion to peach orchard improved soil quality. Biogas residue application reduced soil bulk density quickly in a short term, improved soil TP, effctive N and available P contents significantly, as well as promoted soil TOC and humus acid accumulations to imoprove soil fertility. The results provide technical support for biogas utilization.

It is urgent for agricultural and forestry wastes (AFWS) to be handled efficiently as the generations of them are increasing rapidly in China. The paper studied the bacterial community variations in composting of AFWS with different three microbial agents by PCR-DGGE. Three microbial agents in the research werePhanerochaete chrysosporium(PC) ,Coriolus versicolor(CV) and GP (agent developed from laboratory with high lignocellulose degradation ability). DGGE profiles indicated that the populations of bacteria reduced from warming period to high-temperature phase fistly, then increased till cooling period, and finally descended during maturity period for all the composting treatments. The populations of bacteria in composting with GP innoculation keeped on a high level during high-temperature phase, cooling period and maturity period. In the early phase of the high temperature composting, Bacillus sp., Uncultured Bacillus sp., Pseudomonas sp., Uncultured Pseudomonas sp., Micrococcus sp., Brevibacterium, Sphingomonas sp., Aminobacter aminovorans and Uncultured Acinetobacter sp.were rich, and became the dominant flora of the period. The number of the same dominant flora in AFWS composting with GP and CV innoculations was the most during the high-temperature phase. Simultaneously, the number of the same dominant flora in AFWS composting with GP and PC innoculations was the most during cooling period. Therefore, GP has a good prospect in AFWS composting process for resource utilization.

ASR (Acceleration Slip Regulation) is the extension based on ABS. ABS and ASR are called by a joint name as slip regulation control system. Compared with two wheel drive car, four-wheel drive car has many defects, which is like snatch operation tedious and other defects. This paper has analyzed drive characteristic of four-wheel drive car and established drive simplify mathematical model. According to the mathematical model, we have established drive simulation model in MATLAB/SIMULINK environment, and made simulated analysis of different road surfaces for the model. The result indicated that slip regulation control system played preferable inhibiting effect for drive wheel spike of four-wheel drive car, and it can obtain a certain improvement of dynamic property. It verified feasibility of control algorithm and validity of control strategy at the same time.

To explore purification approach of anaerobic-digested-slurry from cattle dung, this study translated a technology in inorganic coagulation. Under the same condition, a coagulation experiment was carried out by three kinds inorganic coagulants such as polyaluminium chloride (PAC), aluminum sulfate and ferric chloride, respectively, then measured indicators of pH value, BOD5 value, CODcr value, ammonia nitrogen value, turbidity value. Results showed that there was a varying degree of purification effect, and the removal rate of the above indicators increased as the coagulant dosage increasing, the ferric chloride with the dosage of 960mg/L was the best one in purifying effect among the three coagulants. It is feasible that coagulation technology was used to pretreatment biogas slurry from cattle dung, and most of the indicators reached Chinese national standard basically (GB 18596-2001).

The generations of agricultural and forestry wastes (AFWS) are increasing rapidly with developments of agriculture and forestry in China, and AFWS are commonly treated by composting. The objective of this work was to explore the effect of different microbial agents on biodegradation of AFWS. Three microbial agents in the research werePhanerochaete chrysosporium(PC) ,Coriolus versicolor(CV) and GP (agent developed from laboratory with high lignocellulose degradation ability). All the composts inoculated the different microbial agents matured in 58 days. Compared with CK(without exogenous micro agent), composts with micro agents inoculated increased the duration of high-temperature fermentation period, reduced the maturity time, and increased lignocellulose degradation rate. PC and GP inoculated to AFWS produced the higher quality compost with respect to C/N ratio, GI, pH, total organic carbon (TOC) content, and humic acid content.

A rapid development of intensive livestock and poultry, results in a large number of Aquaculture wastes, it is increasing important that timely consumptive farming wastes, and reduces environmental pollution on protection ecological environment and improving recycling agriculture. In this study, cattle, pigs, sheep, chickens and ducks five categories manure were as material, and it carried out that microbial agents used in compost, equipment, process and control software, and especially passivation of heavy metal residues in manure, degradation technology of estrogen and antibiotics of pollutants. As final, two kind products such as a high—quality organic fertilizer and gardening products, were produced with a better benefits on economic, ecological and social.

We reported the superlattices (SL) thin films of ferroelectric BiFeO3 and ferromagnetic La0.7Sr0.3MnO3 on structure and ferroelectric properties, which fabricate by (radio frequency)-magnetic sputtering. Remarkably, the SL thin film has orientation (100), and the interphases are very distinct. We examined samples by XRD, and Keithley 2400, and the result proves the thin film is SL, which is oriented (001), affected by strain and temperature. And strain affect growing of thin film, and temperature affect electricity property.

Numerous potential inhibitors for prevention of advanced glycation end products (AGEs) formation have been extensively investigated for their in vitro and in vivo features, but it would spend a lot of time studying. In the present study, a unique thermal Fourier Transform Infrared (FTIR) combined system as an accelerated method was attempted to simultaneously determine the thermal-dependent conformational changes of human serum albumin (HSA) in the HSA-ribose mixture and examine the onset of the structural transformation from α-helix to β-sheet structures with or without AGEs inhibitors used. The present results clearly indicate that native HSA had an onset temperature at 96°C for the irreversible thermal-induced structural transition from α-helices to β-sheets, whereas HSA-ribose mixture exhibited its onset temperature near at 78°C due to the early occurrence of glycation. However, the onset temperature of the α-helix to β-sheet transition was gradually changed from 78°C to 96°C by increasing the amount of sodium diclofenac or inositol, which was closed to that of the onset temperature of native HSA. This implies that the thermal-induced transition from α-helix to β-sheet for HSA in the HSA-ribose mixture was effectively prevented after adding sodium or inositol. The present study also suggests that this thermal FTIR technique not only rapidly accelerates the conformational changes of HSA-ribose mixture but also directly detects onset temperature of the α-helix to β-sheet transition in real time. This unique thermal FTIR combined system could be a useful tool to screen and evaluate quickly the glycation-induced conformational changes of proteins in a one-step process.

To investigate the thermal behavior of cocrystal formed between anhydrous theophylline (TP) and anhydrous citric acid (CA) by neat manual cogrinding or thermal treatment, DSC and FTIR microspectroscopy with curve-fitting analysis were applied. The physical mixture and 60-min ground mixture were stored at 55{+-}0.5 Degree-Sign C/40{+-}2% RH condition to determine their stability behavior. Typical TP-CA cocrystals were prepared by slow solvent evaporation method. Results indicate that the cogrinding process could gradually induce the cocrystal formation between TP and CA. The IR spectral peak shift from 3495 to 3512 cm{sup -1} and the stepwise appearance of several new IR peaks at 1731, 1712, 1676, 1651, 1557 and 1265 cm{sup -1} with cogrinding time suggest that the mechanism of TP-CA cocrystal formation was evidenced by interacting TP with CA through the intermolecular O-H{center_dot}{center_dot}{center_dot}O hydrogen bonding. The stability of 60-min ground mixture of TP-CA was confirmed at 55{+-}0.5 Degree-Sign C/40{+-}2% RH condition over a storage time of 60 days. - Garphical abstract: Cogrinding, thermal and solvent-evaporation methods might easily induce the theophylline-citric acid cocrystal formation. Highlights: Black-Right-Pointing-Pointer Cogrinding process could gradually induce the cocrystal formation between TP and CA. Black-Right-Pointing-Pointer The TP-CA cocrystal was formed through the intermolecular O-H{center_dot}{center_dot}{center_dot}O hydrogen bonding. Black-Right-Pointing-Pointer Themore » 60-min TP-CA ground mixture was similar to the solvent-evaporated cocrystal. Black-Right-Pointing-Pointer The thermal-induced TP-CA cocrystal formation was confirmed by pre-heating the physical mixture to 152 Degree-Sign C. Black-Right-Pointing-Pointer The 60-min TP-CA ground mixture was stable at accelerated condition over a storage time of 60 days.« less

The solid-state chemistry of drugs has seen growing importance in the pharmaceutical industry for the development of useful API (active pharmaceutical ingredients) of drugs and stable dosage forms. The stability of drugs in various solid dosage forms is an important issue because solid dosage forms are the most common pharmaceutical formulation in clinical use. In solid-state stability studies of drugs, an ideal accelerated method must not only be selected by different complicated methods, but must also detect the formation of degraded product. In this review article, an analytical technique combining differential scanning calorimetry and Fourier-transform infrared (DSC–FTIR) microspectroscopy simulates the accelerated stability test, and simultaneously detects the decomposed products in real time. The pharmaceutical dipeptides aspartame hemihydrate, lisinopril dihydrate, and enalapril maleate either with or without Eudragit E were used as testing examples. This one-step simultaneous DSC–FTIR technique for real-time detection of diketopiperazine (DKP) directly evidenced the dehydration process and DKP formation as an impurity common in pharmaceutical dipeptides. DKP formation in various dipeptides determined by different analytical methods had been collected and compiled. Although many analytical methods have been applied, the combined DSC–FTIR technique is an easy and fast analytical method which not only can simulate the accelerated drug stability testing but also at the same time enable to explore phase transformation as well as degradation due to thermal-related reactions. This technique offers quick and proper interpretations.

The combination of Fourier transform infrared (FT-IR) microspectroscopy with a thermal analyzer was applied to quickly investigate the solid-state ion-exchange reaction of metoclopramide HCl monohydrate (MCP H(2)O) by clipping MCP H(2)O powder between two KBr or KCl pellets. The physical and ground mixtures of MCP H(2)O or 150 °C-preheated MCP powder and KBr or KCl powders with a weight ratio of 1 : 100 were also prepared and determined by FT-IR microspectroscopy. The samples of MCP H(2)O or 150 °C-preheated MCP were identified by using differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis. The results of present study indicate that the ion-exchange reaction was easily induced between MCP H(2)O and KBr by grinding and heating processes. The possible mechanism of ion-exchange reaction may take place between the HCl salt of MCP H(2)O and a KBr matrix by grinding or heating to yield a mixture of HCl and HBr salts of the MCP sample in the presence of hydrated water. The crystal hydrate played an important role to improve this ion-exchange reaction between MCP H(2)O and KBr. However, no ion-exchange reaction occurred between MCP H(2)O and KCl or between 150 °C-preheated MCP and KBr. The solid-state ion-exchange reaction was more easily determined by this novel thermal FT-IR microspectroscopy than other conventional methods.

The purpose of this study was to investigate the thermal-induced solid-state characterization of metoclopramide hydrochloride monohydrate (MCP H2O) by using a combination of differential scanning calorimetry (DSC) and Fourier-transform infrared (simultaneous DSC-FTIR) microspectroscopy. The DSC and thermogravimetric (TG) analyses were also carried out. The result indicates that a continuous process of dehydration, amorphization and recrystallization for MCP H2O in the solid state was easily evidenced via the thermal responsive IR spectral changes by using this simultaneous DSC-FTIR microspectroscopy. In the heating course, one mole of water was first dehydrated from the MCP H2O sample beyond 77 °C, was then quickly transformed to an amorphous form due to the appearance of weak broad IR bands, and continuously recrystallized from 148 °C by showing the sharp IR bands. This one-step novel simultaneous DSC-FTIR microspectroscopy might be available for studying the changes in the progressive processes of the thermal-dependent solid-state characterizations of drugs.

This work investigated the influence of protonation and hydrogen bonding on intramolecular charge transfer (ICT) through different spacers. Three compounds, DS-NH 2 (with a conjugated double bond), TS-NH 2 (with a conjugated triple bond), and SS-NH 2 (with a flexible saturated bond), possessing the same donor group (aniline) and the same acceptor group (naphthalene) but with different linkages were synthesized for this purpose. The double bond and triple bond spacers provided a more efficient ICT pathway than a flexible saturated bond in the ground state, so an ICT absorption band was observed for compounds DS-NH 2 and TS-NH 2 . Although SS-NH 2 did not exhibit any ICT absorption band, two kinds of intramolecular exciplex emissions were observed depending on the solvent polarity. The excited-state dipole moment of DS-NH 2 is less than that of TS-NH 2 . The ICT absorption and emission bands are quenched by protonation in this system. The influence of hydrogen bonding for DS-NH 2 and TS-NH 2 only occurs in the ground state and disappears in the excited state. The intermolecular hydrogen-bond between SS-NH 2 and CF 3 CH 2 OH molecules block the reorientation of the amino group and prevent the occurrence of the ICT. Therefore, no exciplex emission was recorded for SS-NH 2 in the mixed (CH 2 Cl 2 :CF 3 CH 2 OH) solvents.

A grinding process was used to accelerate the solid-state interaction at the interface between magnesium stearate (MgSt) and captopril (CAP) in the presence or absence of water. The 110 °C-preheated MgSt/CAP or MgSt/CAP ground mixture showed a 5.06% (w/w) or 6.07% (w/w) water content, respectively, which was >4.29% (w/w) for the original MgSt alone. The increased water content in each ground mixture was due to the atmospheric absorption of water caused by grinding. A small infrared (IR) peak at 1562 cm −1 appeared in the IR spectrum of the 110 °C-preheated MgSt/CAP ground mixture, whereas a stronger IR peak at 1541 cm −1 with a shoulder at 1556 cm −1 was observed for the MgSt/CAP ground mixture. These IR peaks were possibly related to the solid-state interaction at the interface between MgSt and CAP via hydrogen bonding of adsorbed water. However, an excess of water added in the MgSt/CAP ground mixture could exacerbate the solid-state interaction of MgSt and CAP to form a stearic acid as evidenced by the IR peak at 1705 cm −1 . This may be due to the neutralization between basic MgSt and acidic CAP. In addition, thermal Fourier transform infrared (FTIR) microspectroscopy also confirmed that the thermal-dependent dehydration process might alter the IR peak intensity of MgSt/CAP ground mixtures.

To better study possible solid-state interactions between captopril (CAP) and different types of lubricants at the surface, grinding process was applied to enhance the probability of reaction. Grinding process was carried out for 5 min at room temperature under 32±5% or 80±5% relative humidity (RH) condition. The physical and ground mixtures of CAP and each lubricant (weight ratio: 1:1) were examined by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) microspectroscopy equipped with or without micro hot stage. The results indicate that CAP did not interact with talc, Precirol or stearic acid even if the grinding process was applied. However, a mixture of CAP and each metallic stearate before and after grinding exhibited a different behavior. Although there was a lack of interaction between CAP and sodium stearate in the course of grinding process, this process could induce the trans–cis isomerization of CAP in the CAP–sodium stearate ground mixture. No evidence was observed to show the solid-state interaction between CAP and monoaluminum stearate, but the grinding process seemed to accelerate the solid-state interaction of CAP with magnesium stearate (MgSt). The fact that solid-state interaction occurred between CAP and MgSt was proven by the shifting of the IR spectral peak of ν as (COO − ) of stearate from 1578 to 1541 cm −1 , due to interaction of the OH group in carboxylic acid structure of CAP with bridging coordination of the COO − group of MgSt via hydrogen bonding of water. The interaction occurred between CAP and MgSt was stopped at 60 °C, due to the dehydration of water from the ground mixture.

Differential scanning calorimetry (DSC) combined with a curve-fitting program was utilized to quantitatively determine the polymorphic composition of famotidine in the compacts prepared by different compression treatments. Two types of famotidine compacts (compact I or II) were prepared by compressing a conical shape or a flattened shape of powder bed of famotidine form B. The compact I was constructed by a transparent region in the center with an opaque region surrounded outside, but the compact II was formed by a whole opaque region only. A drilled disc sample was prepared and then directly determined by DSC analysis. The Raman spectral results clearly indicate that all the compacts whether in any region before DSC determination were only of famotidine form B and independent of compression pressure applied. Under DSC determination, however, the curve-fitted relative compositions of form B in the drilled disc I sample were gradually reduced to 23-24% with the increase of compression pressure, whereas the curve-fitted relative composition of form A was slowly increased up to 76-77%. A transitional phase of famotidine form B (form B*) in the transparent region of the compact I after applying150 kg/cm(2) of compression pressure was easily detected, and then transformed to famotidine form A under DSC heating process. But this transitional phase and polymorphic transformation of famotidine could not be detected by other spectroscopic methods. This suggests that the DSC heating system was a preferred method not only to quantitatively analyze the polymorphic transformation of famotidine but also to find a newly transitional phase of famotidine in the compressed compact.

A push–pull compound with intramolecular charge transfer (ICT) characteristic, 6-Cl-2-StQ-NMe2, was synthesized in this work. The emission maxima of 6-Cl-2-StQ-NMe2 correlates excellently with the static polarity of the environment. In an aqueous solution, 6-Cl-2-StQ-NMe2 was observed to form an ‘H type’ aggregate in the ground state, but deaggregation occurred in the excited state. We find that 6-Cl-2-StQ-NMe2 can be used as a biosensor. Quantitative analysis showed that a linear relationship exists when bovine serum albumin (BSA) concentration is between 40 μg/ml and 5000 μg/ml. While monitoring the conformational change of BSA, the denaturation reaction was observed when the temperature exceeded 60 °C.

Temperature-induced desorption behavior of water from methylcellulose (MC) film was investigated by a novel microscopic Fourier transform infrared (FT-IR) spectroscopy equipped with thermal analyzer (thermal FT-IR microscopic system) and thermogravimetric analysis (TGA). The result indicates that the weight loss of water from MC film was markedly correlated to the IR spectral changes of OH stretching (3000–3800 cm −1 ) and bending (1649 cm −1 ) modes of water molecules. The shift of OH stretching mode from 3461 to 3481 cm −1 was accompanied with the water loss from MC film induced by temperature effect. Two stages of water desorption from MC film were proposed: the first stage within the 35–65 °C had a dramatic IR peak shift from 3461 to 3477 cm −1 and accompanied with a largest weight loss of water from MC film, which might be mainly due to the desorption of free water with minor weakly hydrogen-bonded water; the second stage beyond 65 °C would be desorption of moderately hydrogen-bonded bound water, due to the gradual IR spectral shift from 3477 to 3481 cm −1 and a slower weight loss of water from MC film. The changes in peak area ratio of 1649 cm −1 /1374 cm −1 with the temperature also confirmed the IR spectral peak shift of the OH stretching mode via the water loss from MC film. The temperature-dependent dissociation of intermolecular and intramolecular hydrogen bonds within water molecules and/or between water/MC interaction might be responsible for the desorption kinetics of water from MC film.

In order to investigate the thermal-related properties and thermal stability of 10-hydroxycamptothecin (10-HCPT) in the solid state, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) microspectroscopy were used. A novel combination of FT-IR microspectroscopy with thermal analyzer was applied simultaneously to monitor the dehydration and rehydration processes of the 10-HCPT sample. The thermal-induced decomposition of the 10-HCPT sample was also determined by using electrospray-ion trap mass spectrometry (ES-ITMS). The results indicated that the 10-HCPT sample used in this study was a monohydrate in structure, this form that can dehydrate to an anhydrate form if the temperature goes beyond 90 degrees C. The 10-HCPT anhydrate was first suggested to have two polymorphs, in which the form I might transform to form II when the 110 degrees C-preheated sample was cooled to 30 degrees C. The polymorphic transformation temperature was shown within 90-120 degrees C with 10.46 kcal/mol of enthalpy. The peak at 1723 cm(-1) found in the IR spectrum of 10-HCPT monohydrate might correspond to the hydrogen-bonded CO stretching vibration of lactone, which shifted to 1750 cm(-1) assigned to a free CO group of lactone after the destruction of hydrogen bonding via dehydration. This suggests that monohydrate seems to interact intramolecularly with 10-HCPT by hydrogen bonding. However, the rehydration process of the 10-HCPT anhydrate might cause it to return to being a monohydrate, depending on the storage condition. In addition, the thermal-induced decarboxylation of the solid-state 10-HCPT when the temperature is beyond 226 degrees C was proven by the appearance of a new IR peak at 1701 cm(-1) and one major mass spectral peak at m/z 321. This unique IR spectral peak at 1701 cm(-1) was due to the conjugated carbonyl group in the degraded product of 10-HCPT. The m/z 321 assigned to the decarboxylation of 10-HCPT was equal to the molecular weight loss of 44 from mass spectra; which was consistent with the weight loss of 11.9% (molecular weight of 43.3) from TGA curve of 10-HCPT anhydrate.

By analyzing HyJet V phosphate ester hydraulic oil environmental impacts (oil, etc.) and confounding factors (pH, temperature, etc.), the feasibility was studied for the fluorescence detection of aircraft hydraulic oil leaks. By using the fluorescence spectrophotometer at various acidities and temperatures, the fluorescence properties of HyJet V phosphate ester hydraulic oil, Jet Oil II lubricant and 2197 lubricant were gained. The experimental results are shown as following: The fluorescence peaks of HyJet V phosphate ester hydraulic oil, Jet Oil II lubricant and 2197 lubricant are at 362, 405 and 456 nm, respectively. The impact of temperature on HyJet V phosphate ester hydraulic oil is less effective; Jet Oil II lubricant and 2197 lubricant fluorescence intensity decreases with increasing temperature. When acidity increases, the fluorescence peak of HyJet V phosphate ester hydraulic oil gradient shifts from 370 to 362 nm, and the fluorescence intensity decreases; the fluorescence peak of Jet Oil II lubricant is always 405 nm, while the fluorescence intensity decreases; the fluorescence peak of 2197 lubricant at 456 nm red shifts to 523 nm, and double fluorescence peaks appeare. The results are shown as following: under the influence of the environment and interference factors, the fluorescence characteristics of HyJet V phosphate ester hydraulic oil remain unchanged, and distinguish from Jet Oil II lubricant and 2197 lubricant. Therefore, the experiments indicate that the detection of HyJet V phosphate ester hydraulic oil leak is feasible by using fluorescence method.

The influence of hydrogen bonding and protonation on an intra-molecular charge transfer (ICT) compound, 2,4,6-trimethoxy-2-styrylquinoline (2-StQ-2,4,6–30Me), was investigated in the ground state and the excited state. The acid concentration strongly influences the acid-base reaction between 2-StQ-2,4,6–30Me and trifluoroacetic acid (TFA) in a non-polar solvent. The homoconjugation effect (HE) induced by the presence of an acid was quantified by the red shift of absorption maxima. In strong protic acids, the HE was not observed. For non-polar to moderate polar solvents, the HE value increases as solvent polarity increases. When the solvent dielectric constant was higher than that of TFA, the HE value is reduced when the solvent polarity increases.

2-StQ-2OH possessing a proton donor group (hydroxy) and a proton acceptor group (quinoline) was synthesized in order to study the influence of structural effects on the excited-state proton transfer (ESPT) and tautomerization. The ESPT were observed for ground-state hydrogen-bonding complex between 2-StQ-2OH and 2,2,2-trifluoroethanol (TFE) or with triethylamine. In aqueous solution, ESPT can only be observed in α-cyclodextrin (α-CD) inclusion complex. The dielectric constant values of the α-CD cavities probed by 2-StQ-2OH and 2-StQ-2OMe are 8.5 and 6.3, respectively, because of the difference in size of the probe molecule inside the cavity.

The objective of this study was to investigate the effect of pressure and/or temperature on the polymorphic transformation of famotidine from form B to form A by using a thermal confocal Raman microspectroscopy. A compact with a wide transparent zone in the center and an opaque zone surrounding it was prepared by compressing a conical mass of famotidine form B. Two unique Raman peaks at 2897 and 2920 cm−1 for famotidine forms B and A, respectively, were used as markers. The result indicates that the opaque zone in each compact was composed of famotidine from B, and it did not undergo any polymorphic transformation by preparing with higher compression pressure and/or by heating. The Raman peak intensity ratio of the 2920 cm−1 and 2897 cm−1 bands markedly increased starting from 120 °C for the transparent zone prepared by compressing with 19.61 × 104 kPa pressure, but increased from 100 °C with 49.03 × 104 kPa pressure, indicating the occurrence of thermally induced polymorphic transformation of famotidine from form B to form A. However, the transparent zone prepared by 9.81 × 104 kPa compression pressure retained the same Raman spectrum as that of the famotidine form B, revealing that the thermally induced polymorphic transformation of famotidine was dependent on the pressure applied. There was no polymorphic transformation of famotidine in the transparent zone when it was prepared by a higher compression pressure at a lower temperature or by a lower pressure at a higher temperature. The combined effect of compression and temperature was found to accelerate the polymorphic transformation from form B to form A in the transparent zone of famotidine. Copyright © 2006 John Wiley & Sons, Ltd.

The excited-state reaction of push–pull styryl system was studied in this work. In the excited state, compounds of 2-StP-NMe 2 , 2-StQ-NMe 2 , 4-StQ-NMe 2 and 4-StP-NMe 2 possess a sufficiently large acidity change for the proton transfer process to occur. For compounds 2-StT-NMe 2 and 2-StN-NMe 2 the acidity change is too small to induce the proton transfer process. A new type of excited-state de-hydrogen bond (ESDHB) process was observed in this study. It is possible to explore the polarity and HB effect of solvent simultaneously by using the ESDHB mechanism.

In order to investigate the thermal stability of human serum albumin (HAS) in three different states (aqueous solution, cast film, and solid powder), Fourier transform infrared (FTIR) spectroscopy was applied to determine the protein secondary structural changes of these HSA samples under non-isothermal or isothermal condition. The structural similarity of HSA before and after thermal treatment was also studied to estimate the thermo-reversible property of the HSA in these different states. The results indicate that with the increase of temperature, the maximum peaks at 1652 and 1547 cm(-1) (alpha-helix) shifted to 1647 and 1542 cm(-1) (random coil), respectively. An additional peak at 1620 cm(-1) assigned to intermolecular beta-sheet structure clearly appeared with temperature. The alpha-helix content was found to be reduced in favor of the formation of intermolecular hydrogen-bonded antiparallel beta-sheet structure beyond 60 degrees C in the heating process. From the data of structural similarity, HSA sample whether in solid powder or cast film form exhibited a better thermo-reversible property than HSA in aqueous solution even heating to 200 degrees C.

The attenuated total reflection/Fourier transform infrared technique has been utilized to characterize secondary structural changes in human serum albumin (HSA) before and after protein binding via incubation of HSA in different concentrations of ethanol, captopril or ethanol/captopril mixture. The results indicate that ethanol induced a transition from beta-sheet to an alpha-helical structure and promoted conversion of intramolecular hydrogen-bonded beta-sheet to intermolecular hydrogen-bonded beta-sheet. In contrast, captopril or captopril/ethanol mixture induced conversion of intramolecular hydrogen-bonded beta-sheet to intermolecular hydrogen-bonded beta-sheet and resulted in exposure of the aromatic side-chain groups in the unfolding conformation of HSA. Thus, protein binding between HSA and captopril or captopril/ethanol seems to play an important role in protein secondary structure.

A subtractive similarity method (SSM) was successfully applied to obtain the Fourier transform infrared (FT-IR) spectrum of protein in aqueous solution. Three proteins (albumin, trypsin and hemoglobin) were used as models. A scaling factor, chosen by scaling a “suitable” standard IR spectrum, was applied to the IR spectrum of water, and then the scaled IR spectrum was subtracted from that of the protein in solution in an iterative manner until the IR spectral area between 1480 and 1700 cm −1 of the final spectrum with the highest “similarity” to the same area of the standard IR spectrum was produced. The subtractive IR result was normalized to the standard IR spectrum of the solid or film protein between 1700 and 1480 cm −1 . The best scaling factor was obtained when the value of correlation coefficient was maximum. A baseline flattening method (BFM), that used a scaling factor applied to the IR spectrum of water in an iterative procedure to flatten the baseline in the range 1750–1950 cm −1 , was used for comparison.

Fourier transform IR spectroscopy equipped with attenuated total reflection was used to investigate the cysteine-induced alteration of the protein secondary structure of bovine serum albumin (BSA) in aqueous solution before and after UV-B irradiation. Several amino acids were also studied. The results indicate the unchanged IR spectra of BSA coincubated with amino acids, except cysteine, did not change after 72-h UV-B irradiation. There was no difference in the IR spectrum of the unirradiated BSA coincubated with cysteine. A shoulder at 1620 cm(-1) attributed to the intermolecular beta-sheet structure was observed for the IR spectrum of BSA coincubated with cysteine after 72-h UV-B irradiation. Moreover, the peak intensity at 1303 cm(-1) that is due the alpha-helix structure was reduced, but the peak intensity at 1247 cm(-1) corresponding to beta-sheet structures was increased. Longer UV-B exposure for a BSA solution coincubated with cysteine changed the BSA solution from clear to viscous to gel form in which a transparent gel and another white gel were simultaneously observed. A gradual IR spectral alteration was found for BSA coincubated with cysteine and subjected to increased UV-B irradiation. The longer UV-B irradiation yielded increased intensity at 1620 cm(-1). The second-derivative IR peaks at 1655, 1631, and 1548 cm(-1) were shifted to 1650, 1620, and 1544 cm(-1), respectively, by the increase of UV-B irradiation, suggesting a progressive transformation from an alpha-helix to an intermolecular beta-sheet structure for BSA coincubated with cysteine. This strongly implies that longer UV-B exposure time for the BSA solution in the presence of cysteine did alter the protein secondary structures of BSA more, thus inducing gel formation by protein aggregation.