Conventional Dehydration Research Articles

Dehydration Impact on Antioxidant Potential and Phenolic content of Backhousia citrodora leaves

The most popular method for food preservation is dehydration. In order to enhance the overall quality and prolong the longevity of herbal products, it is imperative to carefully choose optimal dehydration conditions. The dehydration of Backhousia citriodora, also known as lemon myrtle leaves (LML), was conducted via three distinct techniques: conventional dehydration at temperatures of 40, 50, and 60°C (referred to as CD40, CD50, and CD60, respectively); vacuum dehydration at the same temperature as conventional dehydration with a pressure of 50 mbar; and heat pump dehydration at a constant temperature of 45°C. The antioxidant capacities, specifically the radical scavenging activity (DPPH) and ferric reducing antioxidant power (FRAP), along with the total phenolic content (TPC), were evaluated. HPD samples came up second to VD samples in terms of TPC retention, DPPH activity, and FRAP test, whereas CD samples had the lowest biochemical content across all dehydration conditions. The TPC and antioxidant activity in the CD sample exhibited a substantial reduction as the dehydration temperature increased. After dehydration, the CD60 sample had the largest reduction in TPC, DPPH, and FRAP values. Maximising the retention of biochemical content is of utmost importance in post-harvest processing as it serves as an indicator of greater retention. Therefore, the selection of appropriate dehydration techniques and conditions is critical in achieving this objective.

Electrochemical Dehydration of Dicarboxylic Acids to Their Cyclic Anhydrides.

An intramolecular electrochemical dehydration reaction of dicarboxylic acids to their cyclic anhydrides is presented. This electrolysis allows dicarboxylic acids as naturally abundant, inexpensive, safe, and readily available starting materials to be transformed into carboxylic anhydrides under mild reaction conditions. No conventional dehydration reagent is required. The obtained cyclic anhydrides are highly valuable reagents in organic synthesis, and in this report, we use them in-situ for acylation reactions of amines to synthesize amides. This work is part of the recent progress in electrochemical dehydration, which - in contrast to electrochemical dehydrogenative reactions for example - is an underexplored field of research. The reaction mechanism was investigated by 18O isotope labeling, revealing the formation of sulfate by electrochemical oxidation and hydrolysis of the thiocyanate-supporting electrolyte. This transformation is not a classical Kolbe electrolysis, because it is non-decarboxylative, and all carbon atoms of the carboxylic acid starting material are contained in the carboxylic anhydride. In total, 20 examples are shown with NMR yields up to 71 %.

Heavy hydrocarbon recovery with integration of turboexpander and JT valve from highly CO2-containing natural gas for gas transmission pipeline

Demand of natural gas is predicted to increase since many valuable products can be produced. Water and heavy hydrocarbon content are the key for gas pipeline facility. To meet requirement of natural gas transportation, dehydration unit (DHU) and hydrocarbon dew point control unit (DPCU) are necessary to avoid water and hydrocarbon condensation during transmission. The conventional dehydration technology, TEG contactor, can lower water content from 1,304 mg/m3 to 80.35 mg/m3 where the maximum limit of water content in natural gas is 97 mg/m3 to prevent hydrate formation. DPCU is installed to remove heavy hydrocarbon, especially C5+. Integration of JT valve and turboexpander was employed to obtain the low gas dew point. The hot gas stream that entered the JT valve was observed. The lower hot bypass gas was applied, the lower hydrocarbon dew point and the more condensate flowrate was achieved. The highest power generation can be gained at low hot gas flow ratio which also influenced the exit pressure and temperature of compressor. In pipeline simulation, the pressure and temperature drop occurred at the high hot gas rate. To examine the arrival condition, dew point curves were generated and showed that the limitation of hot gas flow ratio has to be below 0.6 to prevent heavy hydrocarbon condensation in pipeline.

Synthesis, structural elucidation and optical activity of symmetric Schiff base-functionalized ferrocenes: Synergetic experimental and DFT insights

A number of Schiff base functionalized derivatives (3a-c) was synthesized from the conventional dehydration of ferrocenecarboxaldehyde and diamine precursors in acetonitrile as a solvent at ambient conditions. IR, UV–Vis, elemental analysis, 1H- and 13CNMR were used to elucidate the novel bis-Schiff base compounds. The nature of electronic absorptions was tracked using Time-Dependent Density-Functional Theory (TD-DFT). The molecular electrostatic potential illuminated that the target compounds are sharing relatively akin electronic distributions. In order to determine the electrophilic and nucleophilic sites, surface analysis of the structures was examined for this purpose. These sites are expected to possess an indispensable role to stabilize and robust the structures via typical hydrogen bonding and non-classical CH···π interactions. Type and influence of solvents on absorption spectra were pursued for the selected model (3a), in which aprotic solvents showed negative solvatochromism (more stable ground state), whereas protic solvents delivered positive solvatochromism (more stable excited state). For example, the metal-to-ligand charge transfer band displayed a gradual shift of the λmax (12 nm) when the type of solvent was switched from polar aprotic (ethyl acetate) to polar protic (methanol) due to the formation of hydrogen bonding, causing bathochromic shift. Eventually, the computationally resulting energy gap of the new products (ΔE) were found to be −4.258 (3a), −4.022 (3b) and −3.105 (3c) eV. These values were compared and found to be in a close level with produced figures from the spectra of density of states and with experimentally determined values using Tauc approach.

Polymeric Encapsulate of Streptomyces Mycelium Resistant to Dehydration with Air Flow at Room Temperature.

Encapsulation is one of the technologies applied for the formulation of biological control agents. The function of the encapsulating matrix is to protect the biological material from environmental factors, while dehydration allows for its viability to be prolonged. An advantage of dehydrated encapsulation formulations is that they can be stored for long periods. However, vegetative cells require low-stress dehydration processes to prevent their loss of viability. Herein we describe the fabrication of a dehydrated encapsulate of the Streptomyces CDBB1232 mycelium using sodium alginate with a high concentration of mannuronic acid; sodium alginate was added with YGM medium for mycelium protection purposes. The encapsulation was carried out by extrusion, and its dehydration was carried out in a rotating drum fed with air at room temperature (2-10 L min-1). The drying of the capsules under air flows higher than 4 L min-1 led to viability loss of the mycelium. The viability loss can be decreased up to 13% by covering the alginate capsules with gum arabic. Compared to conventional dehydration processes, air moisture removal can be lengthy, but it is a low-cost method with the potential to be scaled.

Osmotic dehydration influence on marking nut (Semecarpus anacardium)

Marking nut (Semecarpus anacardium) is one of the underutilized minor crops growing wildly in our country. This fruit has got great medicinal properties and health benefits. But its importance is not completely understood and the fruits go waste. Therefore, it is necessary to develop value-added products and osmotically dehydrated fruits have good potential. The inclusion of an osmotic process in conventional dehydration has two major advantages quality improvement and energy savings. There was a significant difference found in the samples prepared from different pretreatments of osmotic dehydration. Osmotic pretreatment T3 (Sucrose 60º Brix. + 18 hrs of immersion + Drying at 60º C) had a great influence on the quality and organoleptic properties of the fruits with maximum solid gain (86.40 %), carbohydrates (75.78 %) and minimum scores for moisture (13.60 %). Also, the highest scores for organoleptic parameters like colour (4), appearance (4), texture (3.75) and taste (3.75) were recorded in the same sample.

Microwave-assisted preparation of polyphosphoric acid in a continuous-flow reactor

Abstract Polyphosphoric acid (PPA) is widely used in inorganic salt production, petrochemical industry, electronic material preparation and other manufacturing industries. Conventional preparation methods of PPA has disadvantages of pollution, high energy consumption and long production time. To address this problem, microwave continuous-flow preparation may be a desirable way due to its advantages of environmentally-friendly, rapidity and high efficiency. Therefore, to explore the process of preparing PPA by microwave continuous-flow method, a continuous-flow microwave reactor was designed for the dehydration process of orthophosphoric acid to prepare PPA in this paper. The microwave-assisted dehydration process was studied in comparison with the conventional dehydration process and the “closed” microwave-assisted dehydration process in terms of energy efficiency, process times and treatment capacity. The effect of input microwave power, reduced pressure and inlet flow velocity of orthophosphoric acid on the performance of the dehydration process was studied. The results showed that the influence of the microwave power on the temperature rise process during dehydration is greater than that of the reduced pressure. Moreover, the inlet flow rate has a great impact on the treatment capacity and product quality of the dehydration process. Bedsides, the comparison with the other two methods showed that microwave heating can effectively shorten the dehydration time, and the continuous-flow treatment can effectively improve the treatment capacity of microwave heating. The perspectives of the process scale-up by continuous-flow microwave heating method is also discussed.

Effect of Refractance Window on dehydration of osmotically pretreated apple slices: Color and texture evaluation

AbstractThe objective of this research was to explore the advantages of apple slices dehydration (cv. Granny Smith) using a Refractance Window (RW) with and without osmotic dehydration as pretreatment and compared with conventional hot‐air drying considering the quality attributes such as color and texture. For pretreatment, the apple slices were osmotically dehydrated and coupled to a moderate electric field (9.3 V/cm) using a sucrose solution (45°Brix) at 40°C until an Aw = 0.95 was achieved. Then, apple slices (with and without pretreatment) were dehydrated using RW at 55, 75, and 95°C and compared with conventional hot‐air drying at 55°C as a control. The results showed that with dehydration using RW, both with and without pretreatment at 95°C, it was possible to achieve a similar quality of apple slices when compared with conventional hot‐air drying at 55°C, but with a significant reduction in processing time. Additionally, the dehydration process using RW presented anomalous diffusion behavior on apple slices with an α > 1.Practical applicationsRefractance Window (RW) is a technology used for dehydration of fruit and vegetables slices and pulp based on the refractance properties of wet materials. RW has reported promising results in processing time reduction as compared with conventional dehydration methods. In addition, the quality of the end products by RW is higher as compared with conventional drying methods. In this research, we have showed that the final product (dehydrated apple slices) using RW attained quality values (color and texture) similar to those obtained with osmotic dehydration (OD) coupled with moderate electric field (MEF)/hot‐air drying. However, the time spent by RW (50 min) was much lower than OD coupled with MEF/hot‐air drying (240 min). Then, the main advantage of RW is the capacity to dehydrate fruit and vegetables materials using temperatures around 100°C, which allow both, reduce processing time and also attain high‐quality retention.

Méndez-Herrera Technique: New Clearing Technique Proposed for Immature Stages and Internal Structures of Adult Insects

Insects must be preserved before identification. The objective of this work was to propose a fast and effective clearing technique for immature stages, mostly larvae and internal adult structures, for permanent mounting in lamellae, thus reducing time. The technique was modified from the conventional dehydration process. The technique reduced the times for clearing larvae and internal structures of insects without need for dehydration of alcohols that can require 3 or more hours of time.

CO<sub>2</sub> Rich Natural Gas Processing: Technical, Power Consumption and Emission Comparisons of Conventional and Supersonic Technologies

Supersonic separator is investigated via process simulation for treating CO2 rich (>40%) natural gas in terms of dew-points adjustment and CO2 removal for enhanced oil recovery. These applications are compared in terms of technical and energetic performances with conventional technologies, also comparing CO2 emissions by power generation. The context is that of an offshore platform to treat raw gas with 45%mol of CO2, producing a lean gas stream with maximum CO2 composition of ≈20%mol, suitable for use as fuel gas, and a CO2 rich stream that is compressed and injected to the oil and gas fields. The conventional process comprises dehydration by chemical absorption in TEG, Joule-Thomson expansion for C3+ removal, and membrane permeation for CO2 capture. The other alternatives use supersonic separation for dew-points adjustment, and membranes or another supersonic separation unit for CO2 capture. Simulations are carried out in HYSYS 8.8, where membranes and supersonic separation are modeled via unit operation extensions developed in a previous work: MP-UOE and SS-UOE. A full technical and power consumption analysis is performed for comparison of the three cases. The results show that the replacement of conventional dehydration technology by supersonic separators decreases power demand by 8.5%, consequently reducing 69.66 t/d of CO2 emitted to the atmosphere. The use of supersonic separation for CO2 capture is also superior than membranes, mainly due to the production of a high-pressure CO2 stream, that requires much less power for injection compression than the low-pressure permeate stream from membranes. Therefore, the case with two supersonic separator units in series presents the best results: lowest power demand (-23.9% than conventional case), directly impacting on CO2 emissions, which are reduced by 2598 t/d (-27.82%).

Economic evaluation and environmental assessment of shale gas dehydration process

Triethylene glycol (TEG) is widely applied to the removal of water in shale gas. This study presents a framework of economic evaluation and environmental assessment for two TEG-based dehydration approaches, namely, conventional dehydration process and stripping gas dehydration process. The latter one features a higher solvent concentration, at the expense of extra shale gas loss. On the basis of process simulation, the effects of theoretical stage and solvent concentration on economic and environmental performances are investigated for process optimization. A hybrid life cycle inventory (LCI) model that consists of input-output and process-based methods is developed to evaluate the environmental impacts associated with shale gas dehydration. The results show that utility consumption and shale gas loss are dominant sources for the emissions of CO2 and NOx, while soot is mainly derived from embodied emissions. Based on the tradeoff between the total annual cost and environmental impacts, the optimal case with superior economic and environmental performances is acquired. Ultimately, sensitivity analyses are conducted for systematic comparison of two approaches under different compositions of raw shale gas and specifications of water removal.

Development of a techno‐economic framework for natural gas dehydration via absorption using Tri‐Ethylene Glycol: a comparative study on conventional and stripping gas dehydration processes

AbstractBACKGROUNDTo date, none of the existing techno‐economic analyses on natural gas dehydration via absorption using triethylene glycol takes into consideration the profit assessment. This work addresses this shortcoming by developing a techno‐economic framework that evaluates the economic feasibility of three different dehydration processes, i.e., conventional dehydration process, stripping gas dehydration process using sale gas, and stripping gas dehydration process using nitrogen, which can meet the maximum water dew point requirement set by local authorities (e.g., Malaysia) for pipeline‐transported natural gas.RESULTSOur techno‐economic analyses reveal that the maximum water dew point specification of −25 °C can only be achieved by using a stripping gas dehydration process that consumes more than 260 Nm3 h−1 of sale gas or 435 Nm3 h−1 of nitrogen. In particular, the use of sale gas as stripping gas with an optimum flow rate of 260 Nm3 h−1 generates the highest annual net profit margin, of about $29 million. Such a profit margin is higher with respect to the use of nitrogen as stripping gas and the conventional dehydration process by about $1.6 million and $300 000, respectively. The minimum water dew point specification of 5 °C, on the other hand, can be achieved by all three analysed dehydration processes.CONCLUSIONThe use of sale gas as stripping gas becomes more justifiable economically relative to the conventional dehydration process and the other alternative (the use of nitrogen as stripping gas) and when a low water dew point specification of −25 °C is required for natural gas. © 2018 Society of Chemical Industry

Optimization of convective drying assisted by ultrasound for Mango Tommy (Mangifera indica L.)

AbstractConvective drying is a conventional method to prolong the shelf‐life of foods that could negatively affect the product quality due to the long exposure time to high temperature. Ultrasound (US) has been used for reducing the drying time while maintaining the product quality. In this study a Box‐Behnken design of Response Surface Methodology (RSM) was used to evaluate the effects of US time‐frequency (t), US power level (Pot), and hot air temperature (T) on the drying process time (DPT), apparent density (AD), and color difference (ΔE) of the dried mango slices (10.0 ± 1.0% wet basis). Fisher's statistical testing was performed for the analysis of variance (ANOVA) for quadratic regression equations. The optimization goals were to minimize the responses. Modeled optimized conditions were 52–55 °C, 45–60 W, and 3 min/30 min for T, Pot, and t, respectively. Energy consumption and carbon footprint were also estimated during the validation of the optimal drying conditions.Practical applicationsThis research explored the use of response surface methodology polynomial models fitted to the experimental data of US assisted drying assays to find the best values of air temperature, time‐frequency, and power of sonication for minimization of the drying process time (DPT) apparent density, and color difference of mango slices. The results specified ranges for the input‐variables where lower DPT and properly dried mango quality parameters co‐exist with important reductions in operational costs and carbon foot‐print compared with those estimated for conventional dehydration process. These findings are of interest toward the development of greener and more sustainable food drying processes.

A humidity shock leads to rapid, temperature dependent changes in coffee leaf physiology and gene expression.

Climate change is expected to increase the frequency of above-normal atmospheric water deficits contemporaneous with periods of high temperatures. Here we explore alterations in physiology and gene expression in leaves of Coffea canephora Pierre ex A. Froehner caused by a sharp drop in relative humidity (RH) at three different temperatures. Both stomatal conductance (gs) and CO2 assimilation (A) measurements showed that gs and A values fell quickly at all temperatures after the transfer to low RH. However, leaf relative water content measurements indicated that leaves nonetheless experienced substantial water losses, implying that stomatal closure and/or resupply of water was not fast enough to stop excessive evaporative losses. At 27 and 35 °C, upper leaves showed significant decreases in Fv/Fm compared with lower leaves, suggesting a stronger impact on photosystem II for upper leaves, while at 42 °C, both upper and lower leaves were equally affected. Quantitative gene expression analysis of transcription factors associated with conventional dehydration stress, and genes involved with abscisic acid signalling, such as CcNCED3, indicated temperature-dependent, transcriptional changes during the Humidity Shock ('HuS') treatments. No expression was seen at 27 °C for the heat-shock gene CcHSP90-7, but it was strongly induced during the 42 °C 'HuS' treatment. Consistent with a proposal that important cellular damage occurred during the 42 °C 'HuS' treatment, two genes implicated in senescence were induced by this treatment. Overall, the data show that C. canephora plants subjected to a sharp drop in RH exhibit major, temperature-dependent alterations in leaf physiology and important changes in the expression of genes associated with abiotic stress and senescence. The results presented suggest that more detailed studies on the combined effects of low RH and high temperature are warranted.

Expression of dead box 1 gene in neuroblastoma

Objective To detect the expression of dead box 1 (DDX1) gene in tumor tissue and pericarcinomatous tissue of clinical neuroblastoma(NB) samples, and explore the relationship between DDX1 and NB. Methods Five cases of pathological specimens in children with NB were chosen from Department of Pathology, the First Affi-liated Hospital of Xinxiang Medical University between January 2012 and December 2014.In the 5 cases, 3 cases were male, 2 cases were female, the age of 1-5 years old, average age (2.1±1.6) years.The NB tissue and pericarcinomatous tissue (pericarcinomatous tissue was normal tissue which was at least 2 cm from the tumor tissue) of 5 children were collected and fixed in 40 g/L formaldehyde solution.Then with the conventional dehydration, embedding, sectioning, dewaxing, hydration, antigen repair, add primary antibodies, secondary antibodies, diaminobenzine chromogenic.The expressions of DDX1 in tumor tissue and pericarcinomatous were observed with light microscopy and with semi-quantitative analysis.(1)Staining degree: no staining with 0 score; light staining with 1 score; medium staining with 2 scores; deeply staining with 3 scores.(2)Positive cells proportion: positive cells proportion 61% with 3 scores.Final scores were a half of the sum of staining degree score and positive cells proportion score, final score within 0-1.0 with-, 1.1-2.0 with+, 2.1-3.0 with+ +, 3.1-5.0 with+ + +. Results DDX1 were expressed in NB and pericarcinomatous tissues, but visible DDX1 positive staining number more and deeper in NB, DDX1 positive staining number less and light in pericarcinomatous tissues.Five cases of pericarcinomatous tissues immunohistochemical semi-quantitative score were negative and final scores were 1.0 score or less, the mean value was 0.5 score.NB immunohistochemical semi-quantitative score were+or+ +and final scores were 1.5 score or higher, the mean value was 1.8 scores, the expressions of DDX1 were significantly higher in NB than the pericarcinomatous tissues. Conclusions DDX1 is highly expressed in NB, which may contribute to the development of NB.This suggest DDX1 may serve as an oncogene and play a catalytic role in the development of NB, which provides a clinical evidence for the follow-up study. Key words: Neuroblastoma; DDX1 gene; Immunohistochemistry

Fuel-based ethanol dehydration process directly extracted by gasoline additive

To reduce the heavy energy consumption of the conventional dehydration process of bioethanol production from biomass fermentation broth, this work aims to develop a fuel-based ethanol dehydration process directly extracted by gasoline additive. Methyl tert-butyl ether (MTBE) is screened and validated as an available entrainer of heteroazeotropic distillation from gasoline additives by analyzing and determining residue curve maps on the basis of simulation and experimental method. Two fuel-based ethanol separation processes with MTBE as entrainer, i.e. direct-cycle scheme and three-column scheme, are proposed and optimized by using ASPEN PLUS. It indicates that the proposed dehydration process with MTBE as entrainer can significantly reduce the energy and entrainer consumption, and the product can be directly used in gas pool. The techno-economic evaluation indicates MTBE scheme with 8000ton/year ethanol production presents lower capital and utility costs than isooctane scheme.

Quality changes in osmotically dehydrated banana var. ‘Robusta’ and ‘Ney Poovan’ as affected by syrup concentration and immersion time

Banana is one of the most important fruit crops of India with an annual production of 264.7 lakh tonnes having great socio-economic significance. It is a highly perishable fruit suffers from high post harvest losses to an extent of about 20 to 40 %. Therefore, it is necessary to develop shelf stable value added products and the osmotically dehydrated slices have good potential. The inclusion of osmotic process in conventional dehydration has two major advantages of quality improvement and energy savings. ‘Robusta’ and ‘Ney Poovan’ cultivars varied in their slice recovery, size, TSS, acidity and sugar contents. Statistically significant variations were observed for moisture content, sugars, titrable acidity, NEB and sensory quality parameters of dehydrated slices. Osmotic pretreatment of 70°Brix syrup for 24 h resulted in maximum reducing sugar (53.78 %), non-reducing sugar (19.93 %) and total sugar (73.73 %) in banana slices. Samples from ‘Robusta’ had higher acidity (1.31 %) than the ‘Ney Poovan’ (1.00 %). However, osmotic pretreatment with 60°Brix sugar syrup for 24 h resulted in best quality products with a sensory score of 83.5 as compared to 65.0 in control. Osmotically dehydrated slices of ‘Robusta’ were significantly superior than ‘Ney Poovan’

Optimization of Carboxymethyl Cellulose and Calcium Chloride Dip-Coating on Mushroom Slices Prior to Hot Air Drying Using Response Surface Methodology

This paper deals with the key issue of the coating technology applied to button mushroom (Agaricus bisporus) slices prior to convective drying. Response surface methodology (RSM) was used to predict the effects and to optimize the concentrations of carboxymethyl cellulose (CMC) (0–3% w/w) and CaCl2 (0–2% w/w) on the quality of dried mushroom slices. The final product was evaluated in terms of responses such as water absorption capacity (WAC), dry matter holding capacity (DHC), rehydration ability (RA), scavenging effect (SE) assay, shear stress (SS) and color (L0 – L and ΔE). The results showed that WAC, RA, SE and SS increased and L0-L and ΔE decreased with CMC concentration increase. Based on response surface and desirability functions, the optimum product qualities in terms of RA (0.50), SE (78.51%), L0-L (20.86), ΔE (27.73) and SS (307.01 N/cm2) responses were obtained at 3% CMC concentration. Practical Applications Fresh mushrooms are very perishable and usage of the best postharvest techniques to enhance the shelf life and to maintain their quality plays a crucial role for commercialization. Materials with high moisture content such as mushrooms do not have a stable structure necessary during conventional dehydration; therefore, a special process must be developed to provide a crispy dried product. Using carboxymethyl cellulose (CMC) as a coating agent provided dried mushroom slices with better quality attributes, including more rehydration ability, brighter color and higher nutritional value (more antioxidant properties).

Facile Botanical Templating Strategies for the Growth of Porous Metal Oxides in Artificial Leaf-Like Macroscale Structures for Potential Use in Energy Related Catalysis

ABSTRACTA major challenge in utilizing living botanical materials, such as cellular leaf structures, as templates is that they are filled with water and conventional dehydration strategies often collapse or degrade the intricate botanical structure. This restricts the ability to introduce water reactive precursors into such structures. We have developed a room-temperature chemical method using acidified 2,2-dimethoxypropane to dehydrate water-rich botanical materials (e.g., fern leaves and water-rich jade succulents). This mild dehydration process leaves much of the porous cellular leaf structure intact even with ∼90% mass loss. These chemically dehydrated templates have been utilized in the growth of porous and ordered leaf replicate structures consisting of TiO2 and SiO2 via sol-gel precursor impregnation methods. These white metal oxide products exhibit external and internal structures that look very similar to their original templates, but are shrunken intact versions of the original. This paper details the chemical procedures that enable one to effectively use sensitive botanical templates in metal oxide growth. The physical and structural properties of several dried porous templates and macroporous anatase TiO2 and amorphous or crystoballite SiO2 products will be described. Recent efforts to use these botanical templates to produce other porous metal oxides (e.g., Co3O4, NiO, and CuO) using both halide and acetate precursor impregnation strategies are noted. Porous metal oxides with interconnected pore walls may have use in electrochemical energy storage systems, including in photocatalytic, photovoltaic or battery systems.

The effect of conventional dehydration versus that of rapid ultrasonic dehydration on tis-sue slices of femoral heads from 510 patients

Objective To compare the effect of conventional dehydration with that of rapid ultrasonic dehydration by analyzing the results of tissue slices of femoral head specimens with HE stainning from 510 patients. Methods The femoral head specimens were sawn into two pieces of slice in 2cm × 2cm × 0.3cm; 30% formic acid-decalcification solution was used to make the speimens decalcified in 16-18 hours ; then the pieces of slice were treated by conventional dehydration or ultrasonic rapid dehydration. After being paraffin-embedded, sliced？？, and stained, the clarity and completeness of the tinct organizational structure of the specimens with HE stainning were observed. Results The effect of rapid ultrasonic dehydration was slightly better than conventional dehydration for the tissue slices of femoral head specimens with HE stainning. But there was no statistical significance between the two methods （ P〉 0.05 ）. Conclusions After decalcification of bone tissues, rapid ultrasonic dehydration can be used to replace conventional dehydration for obtaining better tissue slices with HE staining. Rapid ultrasonic dehydration shortens the time of pathological results, which can satisfy the demand for clinical work. Key words: Femoral head; Rapid ultrasonic dehydration; Conventional dehydration