Small Amount Of Water Research Articles

Robust and adhesive double-solvent phase change hydrogel with reversible transparency and shape memory for thermal management and information encryption

The excellent energy storage capacity of solid–liquid phase change materials has attracted considerable attention, but the vulnerability to leakage limits their applications. Therefore, the development of composite phase change materials has become a hot research topic in recent years. Therefore, a double-solvent (DS) phase change hydrogel (PCH) prepared by random copolymerization of acrylic acid (AA) and hydroxyethyl methacrylate (HEMA) with water and polyethylene glycol (PEG) as solvents was proposed. The phase transition enthalpies of melting and crystallization of the gel reached 116.2 J·g−1 and 113.5 J·g−1, respectively. PCH exhibits good morphological stability while storing thermal energy, which can effectively encapsulate phase change materials without leakage at high temperatures and be recyclable. PEG is used as both solvent and phase change part and the prepared gel reveals a high phase change material loading rate (76.2%), high breaking stress (4.7 MPa) and excellent compression resistance (1.2 MPa), superior to existing counterparts. The presence of a small amount of water in the system endows the gel with certain flexibility. Moreover, due to the solid–liquid phase transition behavior of PEG during temperature changes, PCHs possesses reversible adhesion and transparency, as well as shape memory properties. In addition, its low thermal conductivity and high energy storage efficiency make it perform well in the field of infrared stealth.

A simple method for rapid removal of the memory effect in cavity ring-down spectroscopy water isotope measurements.

The accuracy determined in the routine analysis of water isotopes (δ17 O, δ18 O, δ2 H) using cavity ring-down spectroscopy is greatly affected by the memory effect (ME), a sample-to-sample carryover that biases measurements. This study aims to develop a simple method that rapidly removes the ME. We developed a method, designed for the Picarro L2140-i, that removes the ME by injecting small amounts of water with an extreme isotopic value ("kick") in the opposite direction of the ME. We conducted 11 experiments to identify the optimal kick for pairs of isotopically enriched and depleted samples. Once quantified, the optimal kick was used to create an ME-free, unbiased calibration curve, which was verified using international and internal lab standards. Our kick method removes the ME very efficiently in half the time it takes for experiments without a kick. The optimal number of kick injections required to minimize stabilization time between standards of different compositions is three injections of δ2 H ≈ -1000‰ water per a 100‰ difference between standards. Three runs of routine measurements using the kick method resulted in uncertainties of 0.03‰, 0.2‰, and 5 permeg for δ18 O, δ2 H, and 17 O-excess, respectively. This study demonstrates a new method for rapidly removing the ME. Our kick protocol is a readily available, cheap, and efficient approach to reduce instrumental bias and improve measurement accuracy.

4-(4-Ethoxyphenyl)-5-(4-methoxyphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one

A new triazol-3-one resulted unexpectedly from the reduction reaction of a heterocyclic thioketone using sodium borohydride in pyridine containing a small amount of water. The structure of the new compound was characterised using FT-IR, 1D and 2D NMR, and HRMS spectroscopic methods.

Corrosion Potential Oscillation of Iron Electrodes in Nitric Acid

Although iron dissolves in diluted nitric acid solutions, it does not dissolve in concentrated solutions because of surface passivation. When a small amount of water is added to a concentrated solution, the dissolution and passivation of iron occur alternately, and the amount of gaseous products generated by nitric acid reduction varies in an oscillatory manner. During the corrosion process, the corrosion potential of iron oscillates spontaneously. In this study, we investigated the factors that cause oscillations in corrosion potential through electrochemical measurements using a three-electrode system and numerical simulations. The study revealed that an N-shaped negative differential resistance characteristic of iron oxidation plays a vital role in the oscillation of the corrosion potential and, simultaneously, the reduction of nitric acid results in oscillation. We considered metal corrosion has essential factors resulting in oscillatory instability. Thus, the corrosion potentials of various metals are expected to oscillate spontaneously under the appropriate conditions.

Effect of water on the dissolution of flax fiber bundles in the ionic liquid 1-ethyl-3-methylimidazolium acetate

This work investigated the dissolution rate of flax fibers in the ionic liquid 1-ethyl-3-methylimidazolium acetate [C2mim] [OAc] with the addition of a cellulose anti-solvent, water. The dissolution process was studied as a function of time, temperature and water concentration. Optical microscopy is used to analyse the resultant partially dissolved fibers. Distilled water was added to the solvent bath at the concentrations of 1%, 2% and 4% by weight in order to understand its influence on the dissolution process. The effect of the addition of even small amounts of water was found to significantly decrease the speed of dissolution, decreasing exponentially as a function of water concentration. The resulting data of both pure (as received from the manufacturers) ionic liquid and ionic liquid/anti-solvent mixtures showed the growth of the coagulated fraction as a function of both dissolution time and temperature followed time temperature superposition. An Arrhenius behavior was found, enabling the measurement of the activation energy for the dissolution of flax fiber. The activation energy of the IL as received (0.2% water) was found to be 64 ± 5 kJ/mol. For 1%, 2% and 4% water systems, the activation energies were found to be 74 ± 7 kJ/mol, 97 ± 3 kJ/mol and 116 ± 0.6 kJ/mol respectively. Extrapolating these results to zero water concentration gave a value for the hypothetical dry IL (0% water) of 58 ± 4 kJ/mol. The hypothetical dry ionic liquid is predicted to dissolve cellulose 23% faster than the IL as received (0.2% water).

A small amount of water reduces the friction of the preferentially oriented montmorillonite gouge

The presence of smectite may control the updip seismogenic boundary of a subducting plate. The smectite near the boundary can be dehydrated and highly preferentially oriented in the smectite-to-illite transition zone. Herein, the frictional properties of preferentially oriented (PO) montmorillonite gouge were examined under dry conditions. Highly PO montmorillonites were prepared as self-supporting sheets, which were dried at 70–200 °C for 12 h before conducting shear experiments. The double direct-shear tests on these PO sheets and nominally randomly oriented (NRO) montmorillonite were conducted at room temperature and dry conditions under applied normal stress from 5 to 40 MPa. The friction coefficients of the NRO gouges (0.42–0.45) were not affected by drying temperature, while those of the PO sheets increased with increasing drying temperature from 0.32 to 0.52 at normal stress of 5 MPa. The estimated water contents for both samples depended on the drying temperature, but it was significantly lower (<1 mass%) than the upper limit of the water content of 4.5 mass% for dry friction as estimated from previous studies. A small amount of water (<1 mass%) might become vapor by frictional heating in the low porosity, low permeability PO smectite gouge and increased pore pressure resulting in the decrease of the effective normal stress and shear stress. Although there is much to consider under the natural conditions of smectite-to-illite transition, it was found that preferentially oriented smectite showed a low friction coefficient, even in a dehydrated state.

Shape Factor for Analysis of a Slug Test

Hydraulic conductivity is an essential parameter for groundwater investigation and management. A simple technique for determining the hydraulic conductivity of aquifers is the slug test, which consists of measuring the water level in a well after the sudden removal or injection of a small amount of water. The interpretation of a slug test is based on a geometry-dependent shape factor, for which various empirical relationships and approximate solutions have been proposed in the literature. In this study, shape factors are derived numerically for slug tests performed in monitoring wells with screens unaffected by aquifer boundaries. Also presented is a new approximate analytical solution for predicting shape factors for well screens with a large aspect ratio. A comparison with earlier methods reported in the literature shows that our results match or exceed them in terms of accuracy. The approximate analytical solution is promising because it is accurate and very easy to apply in practice.

Thermomechanical Plasticization of Fruits and Vegetables Processing Byproducts for the Preparation of Bioplastics

AbstractByproducts of the processing of foods are usually non‐edible residues that are typically discarded, even though they contain large amounts of natural polymers with great potential in bioplastics and biocomposites preparation. Herein, a new method of production of vegetable‐waste‐derived biocomposites is developed. It consists of the thermomechanical processing of different residues in the presence of small amounts of water, representing an advancement in the state‐of‐the‐art in the complete conversion of fruit and vegetable biomass into biocomposites. In particular, carrot pomace (CP) is processed by compression molding at different temperatures, pressures, and times. Selected processing conditions are also applied to other food processing byproducts. The morphological, mechanical, barrier, optical, and antioxidant properties of the obtained biocomposites and their interaction with water in terms of moisture content, water solubility, and moisture absorption are reported here. Results indicate that biocomposites obtained by this method present similar properties compared to biocomposites prepared by acid or alkaline hydrolysis of biomass reported in the literature, but still inferior compared to bioplastics currently in the market. Improvements in the materials' interaction with water are highlighted here as the necessary next step to achieving the transition toward greener bioplastics.

Evaluation of the Parameters of the Dispersed Stream Generated by Various Types of Water Nozzles

Aim: The purpose of the research was to determine the parameters of the micro- and macro-structure of the streams generated by nozzles of different types, and to identify potential applications of the tested water nozzles, including firefighting and air pollution removal. Introduction: TF6 FCN, TF6 V, NF 15 and CW 50 water nozzles were tested. At supply pressures of 0.2 MPa, 0.4 MPa and 0.6 MPa, the basic parameters of micro- and macrostructure of the streams were measured and determined: flow rate, spray angle, mass distribution of liquid on the surface (spray intensity), non-uniformity of spray density distribution, and average droplet diameters and spray spectrum. A sputter spectrum analyser, using the photoelectric method, was used to determine the microstructural parameters of the stream. Project and methods: Badaniom poddano dysze wodne TF6 FCN, TF6 V, NF 15 oraz CW 50. Przy ciśnieniu zasilania równym 0,2 MPa, 0,4 MPa oraz 0,6 MPa zmierzono i wyznaczono podstawowe parametry mikro- i makrostruktury strumieni: natężenie przepływu, kąt rozpylenia, rozkład masowy cieczy na powierzchni (intensywność zraszania), nierównomierność rozkładu gęstości zraszania oraz średnie średnice kropel i widmo rozpylenia. Do określenia paramentów mikrostrukturalnych strumienia zastosowano analizator widma rozpylenia, wykorzystujący metodę fotoelektryczną. Results: The tested nozzles generated dispersed streams with different parameters. Among the analysed nozzles, the highest degree of dispersion was obtained for the TF 6 FCN sample, whose average Sauter mean diameter (SMD) reached a value of 217.3 μm. In comparison, for the NF15 nozzle this parameter was 945 μm. The spray spectra indicate a high homogeneity of water dispersion in the stream produced by the nozzles TF 6 FCN and CW 50. From the distribution of mass sprinkling density, the CW 50 nozzle shows the greatest uniformity of spraying. At the same time, however, it reports a small amount of water, since the value of the spray density for this product did not exceed 100 g/( m2 · s), while for the NF 15 nozzle it was more than 2,700 g/( m2 · s). The obtained spray angles were close to those declared by the nozzle manufacturer. In the tests of all samples, a slight effect of supply pressure on the values of this parameter was observed. Conclusions: Among other things, the tests made it possible to conclude that in the range of supply pressures of 0.2÷0.6 MPa, the values of disperse angle and spray area of the analysed nozzles were constant or the recorded differences were insignificant. In addition, it was determined that in the case of nozzles with full spray cones, an increase in supply pressure (within the range of declared operating values) has little effect on changing the parameters of the micro- and macro-structure of the stream. The conducted tests showed the potential use of two nozzles (TF6 FCN, CW 50) in low-pressure fog extinguishing systems producing fog with SMD droplet diameters &gt; 200 μm. For the absorption of hazardous substances, it is recommended to use nozzles with a large spray angle and a full spray cone, which, as tests have shown, produce uniform streams with small droplet diameters. Keywords: water nozzles, water spray, spray spectrum, mass spray density, water mist

Experimental investigation of novel ternary amine-based deep eutectic solvents for CO2 capture.

This study investigates the effect of using water as a low-viscosity component in ternary amine-based deep eutectic solvents (DESs) on the physicochemical properties, thermal stability, and CO2 absorption capacity of the resulting DESs. It should be emphasized that water is a component of the ternary DES. The effect of water content in the DES, type of hydrogen bond acceptors (HBAs), hydrogen bond donors (HBDs), and HBA:HBD ratio on the above parameters was investigated. Moreover, the effect of temperature and pressure on the CO2 absorption capacity of DESs was predicted using the predictive model COSMO-RS. This model was also used to predict the CO2 solubility in the DESs and the results were compared with the experimental values. The results showed that the addition of small amounts of water, e.g., 5 and 10 wt% during preparation, can significantly decrease the viscosity of the resulting DESs, up to 25% at room temperature, while maintaining the high CO2 absorption capacity and high thermal stability. The ternary DESs based on MEA exhibited a high CO2 absorption capacity of 0.155-0.170 g CO2 / g DES. The ternary DESs were found to be thermally stable with a decomposition temperature of 125°C, which promotes the use of such solvents in post-combustion capture processes. Finally, COSMO-RS proved to be a suitable tool for qualitative prediction of CO2 solubility in DESs and demonstration of trends related to the effects of temperature, pressure, molar ratio, water content, HBD and HBA on CO2 solubility.

Subcritical crack growth and fracture behavior of three rocks containing quartz under wet and dry conditions

Understanding the subcritical crack growth behavior of rocks under water-rock interaction is essential to evaluate the stability of deep resource extraction and the integrity of nuclear waste disposal or CO2 sequestration. Using the double-torsion technique, we performed relaxation tests on three rocks with different quartz contents, namely, quartz amphibolite, white sandstone and red sandstone, in air environment and in introduced water conditions to systematically investigate the effect of water on subcritical crack growth behavior of three rocks. The subcritical fracture behavior of the rock responded very rapidly to water: when water entered the crack tip, 1) the crack velocity increased with decreasing of stress intensity factor; 2) the slope of the load decay curves increased abruptly; and 3) the strain values at the bottom monitoring points extracted from three-dimensional digital image correlation increased immediately. Compared with the air environment, the subcritical crack growth indexes of quartz amphibolite, white sandstone and red sandstone in fluid conditions were reduced by 27.08 %, 80.81 % and 86.14 %, respectively, and the crack velocities were increased by one order of magnitude. The Ka values of quartz amphibolite, white sandstone and red sandstone were less sensitive to water than the subcritical crack growth indexes, decreasing by 9.43 %, 17.35 % and 37.33 %, respectively. Data from these tests reveal that the subcritical fracture properties of the three rocks were degraded despite the small amount of water flowing through the sample, proving that the long-term effects of water on actual engineering cannot be ignored.

Studying the impact of humidity on the performance of THGEMs

In this study, we investigate the impact of humidity on the performance of a THGEM operated with an Ar-CO2 gas mixture. The water content is introduced in a range of 0–4000 ppmV. It is observed that the presence of increased humidity does not degrade any of the studied performance criteria. On the contrary, our measurements suggest an improvement in discharge stability with increasing humidity levels at the highest gains and fields. No significant difference is observed at the lower gains, indicating that humidity helps to avoid spurious discharges related to electrode defects or charging-up of the insulating layers. We conclude that adding a small amount of water to the gas mixture may be beneficial for the stable operation of an MPGD.

Study on the Treatment of Simulated Recirculating Mariculture Wastewater by Thiosulfate-Based Autotrophic Denitrification

In this study, a sulfur-based autotrophic denitrifying filter (SADF) was developed for the purpose of removing nitrate from simulated recirculating mariculture wastewater. Results showed that over 90% of the nitrate could be effectively eliminated by utilizing thiosulfate as the electron donor, with a molar ratio of thiosulfate-S to nitrate molar ratio of 2:1 or greater. Additional batch tests confirmed that thiosulfate was a suitable sulfur source for nitrate removal even without prior accumulation of the biomass to nitrite. Excess thiosulfate had a minor impact on N-removal efficiency, so an external sulfur source was not required for nitrate removal, however, it could still help to reduce nitrate accumulation and water replacement to some extent. High-throughput sequencing results illustrated that Thiomicrospira and Thioalkalivibrio were the dominant autotrophic denitrifying genera in the SADF, while Thiomicrospira was more significantly affected in the case of insufficient sulfur sources. As the issue of nitrate accumulation in the mariculture recirculating system has been resolved, only a small amount of water needs to be added to the system daily. Therefore, the thiosulfate-based SADF process has the potential to be implemented for nitrate removal in mariculture systems, which could present a promising sustainable solution to the nitrate pollution issue.

Development of a new age-appropriate, chewable tablet of mebendazole 500 mg for preventive chemotherapy of soil-transmitted helminth infections in pre-school and school-age children

The aim of this study was to develop an age-appropriate tablet of mebendazole 500 mg to be used in large donation programs by the World Health Organization (WHO) for preventive chemotherapy of soil-transmitted helminth (STH) infections in pre-school and school-age children living in tropical and subtropical endemic areas. To that end, a new oral tablet formulation was developed that can be either chewed or given to young (≥1 year old) children by spoon after rapid disintegration to a soft mass with the addition of a small amount of water directly on the spoon. Although the tablet was manufactured using conventional fluid bed granulation, screening, blending, and compression processes, one of the main challenges was to combine properties of a chewable, dispersible, and regular (solid) immediate release tablet to meet the predefined requirements. The tablet disintegration time was below 120 s, allowing for administration by the “spoon method”. The tablet hardness was higher (160–220 N) than normally applicable for chewable tablets, permitting shipment along a lengthy supply chain in a primary 200-tablet count bottle packaging. In addition, the resulting tablets are stable for 48 months in all climatic zones (I–IV). In this article, several aspects of the development of this unique tablet are described, including formulation, process development, stability, clinical acceptability testing, and regulatory filing.

Plasma assisted dry reforming of methane: Syngas and hydrocarbons formation mechanisms

Plasma reactions of CO2 + CH4 mixtures have been proposed as a suitable process for the dry reforming of methane. Without specific catalysts, most studies report the formation of CO and H2 as main reaction products and arise the question whether CHx radicals coming from CH4 may interact with intermediate species formed by electron impact dissociation of CO2, a critical step for the formation of high added value oxygenated compounds. We have addressed this question studying the CO2 + CH4 plasma reaction in a ferroelectric-moderated packed-bed reactor varying the reactants ratio. Analysis of the reaction products by mass spectrometry and the plasma reaction intermediates by optical emission spectroscopy suggest that few direct cross-link interactions exist between intermediate plasma species issued from CH4 or CO2. This preliminary evidence is corroborated by experiments using 13CO2 instead 12CO2 as reactant. The isotope labeling procedure has proved that plasma reaction mechanisms of CO2 and CH4 molecules proceed almost independently, with the formation of small amounts of water and the removal of carbon deposits resulting CH4 plasma decomposition as sole evidences of cross reactions. These results highlight the need of using catalysts to promote specific surface reactions for a better control of the selectivity of the process.

A novel method for pressure-density-temperature-composition reconstruction of water-bearing CO2/CH4-rich geofluids based on a high-precision Raman calibration model

Water-bearing CO2-rich and CH4-rich fluid inclusions are commonly found in various geological environments. Pressure-density-temperature-composition (P-V-T-x) reconstruction of geofluids from such fluid inclusions is fundamental for understanding fluid events related to hydrothermal, metamorphic, and ore-forming processes. Previous methods for P-V-T-x reconstruction of geofluids, such as microthermometry and Raman analysis, often ignore the small amount of water in CO2-rich and CH4-rich fluid inclusions, resulting in obvious errors in composition-density determination, and thus geofluid P-T reconstruction. In the present study, a novel method for P-V-T-x reconstruction of water-bearing binary CO2-rich and CH4-rich geofluids was proposed based on the measurement of the Raman peak positions of water in the vapor phase. Raman spectra of dissolved H2O in vapor-phase CO2/CH4-H2O fluid systems were collected at the P-T range of 10–120 MPa, 100–300 °C, i.e., 0.0091–0.894 of x (H2O) molar fraction, and quantitative models for composition-density calculation of CO2-rich and CH4-rich systems were developed. As the Raman peak positions of dissolved H2O in the CO2/CH4-rich phase are more sensitive in wave number to density changes than the peak positions in previous methods of the CO2 Fermi diad and C-H stretch mode of CH4 the composition–density calculation using the newly developed Raman calibration models was ten times higher in accuracy. As a demonstration, we determined the composition-density properties of the CO2-rich inclusions in quartz veins collected from the Cape Muroto, Shimanto belt, SW Japan; the P-T field constrained by fluid inclusion indicated the heating effect of the gabbro intrusion event.

Rational design of a solvatochromic coumarin aldehyde for the development of an effective water and humidity sensor

Reported herein is the design, synthesis, and water detection application of a highly solvatochromic coumarin derivative (compound 1), whose solvatochromism derives from the presence of both an electron-withdrawing aldehyde (i.e., formyl) substituent, and an electron-donating diethylamino group. Although this compound has been previously reported as a component of larger architectures, its solvatochromic properties as a stand-alone fluorophore have not been reported. Our investigations revealed that compound 1 demonstrated a high degree of fluorescence responsiveness to polar protic solvents, with a particularly strong decrease in its fluorescence occurring in the presence of small amounts of water. This water-based responsiveness was further exploited in the development of a fluorescent water sensor, which responds to both the presence of liquid water and water vapour with rapid, sensitive (detection limits as low as 0.05% (water/acetonitrile; v/v)), and irreversible fluorescence quenching.

Influence of Moisture Content and Dry Density on the Compressibility of Disturbed Loess: A Case Study in Yan’an City, China

Loess is a kind of soil that experiences a long period of deposition, and it is relatively stable under natural conditions. However, in the process of engineering construction in loess areas, the original soil structures of the loess are destroyed, inducing changes in the composition and water content in the loess. These changes may cause different environmental and engineering geologic problems. To reveal the engineering properties of disturbed losses in the Chinese Loess Plateau, the physical properties of 135 groups of disturbed loess samples in Yan’an City were analyzed statistically, and the compression properties of loess with different moisture contents and dry densities were studied by high-pressure consolidation experiments. We elucidate the compressive deformation law for perturbed solids at different moisture contents and dry densities. The experimental results show that the water content rate for the best compaction performance of the disturbed loess is 16%. The compressive deformation coefficient generally decreases with increasing dry density and water content. However, when the soil moisture is low, a small amount of water and salt is concentrated in the contact position of the powder, and the soluble salt is condensed into cement. The molecular forces between particles and the bonding forces of bound water and capillary water are larger. The soil forms a porous structure with coarse grains as the main skeleton, and the cement bonding strength is strong at the contact points of the coarse grains. As a result, the loess shows high intensity at low-water content. This results in a compression-deformation coefficient that increases with dryness density in the small load range.

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Until the end of the Late Pleistocene, the modern river valleys of most of Scandinavia remained buried under the cover of continental ice. The rivers of the region, including the Karelian ones, are distinguished by their geological youth, having formed as fluvial complexes only in the Holocene. The young age, combined with the strength of the crystalline rocks of the Baltic Shield, has affected the fact that the rivers here are characterized by the lack of development of the longitudinal profile. At the base of the thresholds, at which the flow acquires the character of rapid, the processes of formation of miniature scaffolds develop in places. A similar hydraulic situation developed at the front of the degrading glacier. The lower reaches of dams of hydraulic stations are also favorable for a powerful impact on the rock bed. Numerous traces of violent deep erosion, accompanied by the phenomena of indiscriminate erosion and hydrodynamic cavitation, can be found on the kilometer-long sections of the exposed rock bed of semi-mountain streams drained during hydraulic development.A miniature scaffold developed by powerful natural and technogenically provoked floods in the lower part of the large rapid Matkozhnia on the Nizhny Vyg River, in the zone of the White Sea-Baltic Canal, is indicative. Almost the entire route of the canal, starting from Vygozero, is laid along the valley of the Lower Vyg. Only in some sections between the locks, the channel bed was dug away from the river. There, the old valley is preserved either almost dehydrated or with a small amount of water in the rock bed. The bedrock is exposed along the entire riverbed. Small boulders and pebbles of different sizes and grades of rolling can be found only in scattered pockets along the river channel. There numerous glass–like forms of microrelief – with a diameter and a depth of up to the first meters – “glasses” and “wells” are formed on Precambrian crystalline rocks. The contribution of evorsia to the denudation of crystalline slates in the bottom of the Vyga Valley on the rapid Matkozhnia is very significant, although the evorsion-cavitation effect itself is carried out rarely and for a limited time. Similar processes of natural origin operated before the creation of reservoirs on rapid-waterfall sites in the Vyga Valley and other large rivers of Karelia; they were caused by natural factors. Emergency descents of water through high spillway dams could increase the destructive effect of the stream on its root bed. So, in particular, the formation of evorsion microforms in the bed of the Lower Vyg at the rapid Matkozhnia is partially technogenically caused. Karelian cavitation-evorsion complexes of forms associated with hydrospheric catastrophes can be considered as miniature analogues of giant Late Pleistocene scablands of the northwestern USA.

Water Content-Controlled Formation and Transformation of Concomitant Pseudopolymorph Coordination Polymers.

Two concomitant pseudopolymorph coordination polymers {[Cd2L2(OAc)4]·2DMSO} n (1) and {[CdL(OAc)2]·2.75H2O} n (2) were synthesized by self-assembly of 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene (L) and cadmium acetate in DMSO. Single-crystal X-ray diffraction confirmed that 1D ladder structural motifs exist for pseudopolymorphs 1 and 2 which contain DMSO and water guest molecules, respectively. Our study illustrated the active role of solvent water content in obtaining compound 2. We find that the presence of water as an impurity in the DMSO solvent creates the possibility of formation of concomitant pseudopolymorph coordination polymers which is a unique event. Furthermore, our analyses showed the effect of environmental humidity on the transformation of unstable compound 1. 1D ladder pseudopolymorphic compound 1 could be transformed to guest-free 1D linear compound [CdL(OAc)2(H2O)] n (3') (the powder form of single crystals of 3) through a scarce case of water absorption from air. Also, the crystalline material of coordination polymer 3 was transformed to coordination polymer 2 through the dissolution-recrystallization structural transformation process in DMF or DMSO. Our study clarified that the amount of water in the reaction container can control the formation of one of the compounds 2 or 3. In the presence of a significant amount of water, compound 3 (coordinated water) will be produced, whereas if a small amount of water is present, compound 2 (uncoordinated water) is prepared as an exclusive product.