Similar Physicochemical Characteristics Research Articles

Assessing the Effect of Weak and Strong Acids as Electrolytes in the Removal of Cesium by Soil Electrokinetic Remediation

The removal of cesium from artificially contaminated soil using electrokinetic remediation with nitric and acetic acid as electrolytes had been evaluated. In this study, uncontaminated soil was taken from four different sampling points (i.e., A, B, C, and D) in Kotagede, Yogyakarta, Indonesia. All samples were prepared as cesium contaminated soil (100 mg CsCl/kg soil), which have similar physicochemical characteristics with Fukushima soil, Japan. The electrokinetic remediation (EKR) was conducted using a graphite electrode in a constant voltage of 1.0 Vcm–1 for 7 days without electrolyte pH control, with 1.0 M nitric and acetic acid as electrolytes. The current profile during the EKR was recorded by a data logger for every 10 min. The remaining cesium in the soil was measured by a flame atomic absorption spectrophotometer at a wavelength of 852.1 nm. The results showed that the type of acid used in the experiments affected the removal of cesium. The highest cesium removal was achieved when nitric acid was used in the experiment and then followed by acetic acid. For all acids, the removal ability of cesium from soil was in the following order: soil C > soil A > soil D > soil B.

Caracterização físico-química e desenvolvimento pós-colheita de jabuticabas (Plinia peruviana e P. cauliflora)

Plinia peruviana and P. cauliflora are Myrtaceae with potential for agricultural exploitation or urban afforestation. However, there is not much information about its characteristics; consequently, making the objective of this work to evaluate morphometry (size, fresh fruit mass, pulp, bark and seeds, pulp yield, number of seeds per fruit and fruit color), chemical composition (soluble solids, acid titratable AT, Ratio and vitamin C content) and post-harvest behavior (chemical composition and loss of fresh mass) of its fruits. The samples studied were rounded, with high water content (83%), high yield of pulp (between 67 and 76%), fresh mass between 5.30 and 6.82 g and more than one seed per fruit. They presented between 11.4 and 12.7 SS, low AT and 19 mg 100 g of pulp-1 of vitamin C. Plinia peruviana and P. cauliflora have shown similar physicochemical characteristics and can be stored for 28 days under refrigeration (≈2oC).

Changes in Bacterial and Fungal Microbiomes Associated with Tomatoes of Healthy and Infected by Fusarium oxysporum f. sp. lycopersici.

Fusarium wilt of tomato caused by the pathogen Fusarium oxysporum f. sp. lycopersici (Fol) is one of the most devastating soilborne diseases of tomato. To evaluate whether microbial community composition associated with Fol-infected tomato is different from healthy tomato, we analyzed the tomato-associated microbes in both healthy and Fol-infected tomato plants at both the taxonomic and functional levels; both bacterial and fungal communities have been characterized from bulk soil, rhizosphere, rhizoplane, and endosphere of tomatoes using metabarcoding and metagenomics approaches. The microbial community (bacteria and fungi) composition of healthy tomato was significantly different from that of diseased tomato, despite similar soil physicochemical characteristics. Both fungal and bacterial diversities were significantly higher in the tomato plants that remained healthy than in those that became diseased; microbial diversities were also negatively correlated with the concentration of Fol pathogen. Network analysis revealed the microbial community of healthy tomato formed a larger and more complex network than that of diseased tomato, probably providing a more stable community beneficial to plant health. Our findings also suggested that healthy tomato contained significantly greater microbial consortia, including some well-known biocontrol agents (BCAs), and enriched more functional genes than diseased tomato. The microbial taxa enriched in healthy tomato plants are recognized as potential suppressors of Fol pathogen invasion.

Development, Chemical, and Sensory Characterization of Liqueurs from Brazilian Native Fruits

ABSTRACT The global market of alcoholic beverages nowadays is more diversified with the insertion of new flavors and new kinds of products. Thus, dry (80 g L−1 of sugar) and creamy liqueurs (344 g L−1 of sugar) of three different Brazilian native fruits (jabuticaba, blackberry, and guabiroba) were produced, and their physicochemical properties, bioactive compounds, acceptance, and purchase intention tests have been evaluated. The six formulations prepared presented similar physicochemical characteristics with different contents of bioactive compounds. Also, the acceptance and purchase intention tests showed a preference for creamy liqueurs of all fruits and preference for the blackberry instead of the other fruits.

Nanocellulose from Industrial and Agricultural Waste for Further Use in PLA Composites

Cellulosic waste has stood out as potential materials for obtaining cellulose, since this raw material is highly available in a wide variety of species. These can be agricultural, forestry, or industrial. Cotton is an agricultural material of high cellulose content and great technological and economic importance. Another source with great potential is the waste from the paper industry. Both materials generate large amounts of waste that were little explored and uncorrected disposed. This work proposes the recycling of these two types of residue through the production of nanocellulose (cotton waste (CW-N) and industrial wastes (IW-N)) and their characterization by Fourier transform infrared spectroscopy, dynamic light scattering, X-ray photoelectron spectroscopy, X-ray diffraction, morphological analysis, and thermal properties. The nanocelluloses (NCs) were incorporated in poly(lactic acid) matrix, and the composites were evaluated mechanically. After the isolation of the nanocelluloses, it was found that both materials showed similar physicochemical characteristics, such as chemical functional groups and atomic composition. However, the morphologies are very distinct: the CW-N is nanofibrillar, with mean diameter around 30 nm, and the IW-N is spherical and irregular, with radius varying from 30 to 100 nm, which can be associated with the different crystalline structure of the materials. The differences in the structure were evaluated through Rietveld Refinement, and the industrial residue showed the presence of impurities in large amounts, and an increase in the cellulosic content after the conversion into nanoscale. The biocomposites showed a significant increase in the mechanical results, with improvement in the tensile strength from 63 to 69 and 78 MPa to agricultural and industrial nanocelluloses, respectively, which is associated with the good stress transfer between the fillers and the matrix and possible interactions between the active sites of PLA and nanocelluloses.

MYL1501D Insulin Glargine: A Review in Diabetes Mellitus.

Subcutaneous MYL1501D insulin glargine 100 U/mL (hereafter referred to as MYL1501D insulin glargine) [Semglee®] is a long-acting human insulin analogue approved as a biosimilar of insulin glargine 100 U/mL (hereafter referred to as reference insulin glargine 100 U/mL) [Lantus®] in various countries, including those of the EU for the treatment of diabetes mellitus in patients aged ≥ 2 years, as well as Japan for diabetes where insulin therapy is indicated. MYL1501D insulin glargine has similar physicochemical characteristics and biological properties to those of EU- and US-sourced reference insulin glargine 100 U/mL, with the bioequivalence of pharmacodynamic and pharmacokinetic parameters between these agents shown in adults with type 1 diabetes. Once-daily MYL1501D insulin glargine demonstrated noninferior glycaemic efficacy to that of once-daily reference insulin glargine 100 U/mL in adults with type 1 or 2 diabetes, with its glycated haemoglobin-lowering benefits maintained over the longer-term (52 weeks) and unaffected by previous insulin exposure. Switching between MYL1501D insulin glargine and reference insulin glargine 100 U/mL did not appear to impact glycaemic efficacy in adults with type 1 diabetes. MYL1501D insulin glargine was well tolerated, demonstrating a safety and immunogenicity profile similar to that of reference insulin glargine 100 U/mL in patients with type 1 and 2 diabetes, and in those with type 1 diabetes switching between the two agents. As expected, hypoglycaemia was the most frequently reported treatment-emergent adverse event. Thus, MYL1501D insulin glargine provides an effective biosimilar alternative for patients requiring insulin glargine therapy.

Preparation and Characterization of Surface Heat Sintered Nanohydroxyapatite and Nanowhitlockite Embedded Poly (Lactic-co-glycolic Acid) Microsphere Bone Graft Scaffolds: In Vitro and in Vivo Studies.

In the context of using bone graft materials to restore and improve the function of damaged bone tissues, macroporous biodegradable composite bone graft scaffolds have osteoinductive properties that allow them to provide a suitable environment for bone regeneration. Hydroxyapatite (HAP) and whitlockite (WLKT) are the two major components of hard tissues such as bone and teeth. Because of their biocompatibility and osteoinductivity, we synthesized HAP (nHAP) and WLKT nanoparticles (nWLKT) by using the chemical precipitation method. The nanoparticles were separately incorporated within poly (lactic-co-glycolic acid) (PLGA) microspheres. Following this, the composite microspheres were converted to macroporous bone grafts with sufficient mechanical strength in pin or screw shape through surface sintering. We characterized physico-chemical and mechanical properties of the nanoparticles and composites. The biocompatibility of the grafts was further tested through in vitro cell adhesion and proliferation studies using rabbit bone marrow stem cells. The ability to promote osteogenic differentiation was tested through alkaline phosphate activity and immunofluorescence staining of bone marker proteins. For in vivo study, the bone pins were implanted in tibia bone defects in rabbits to compare the bone regeneration ability though H&E, Masson’s trichrome and immunohistochemical staining. The results revealed similar physico-chemical characteristics and cellular response of PLGA/nHAP and PLGA/nWLKT scaffolds but the latter is associated with higher osteogenic potential towards BMSCs, pointing out the possibility to use this ceramic nanoparticle to prepare a sintered composite microsphere scaffold for potential bone grafts and tissue engineered implants.

Physicochemical and sensory properties of papaya fruits of elite lines and hybrids

This study aimed to evaluate papaya elite lines and hybrids as to fruit physicochemical and sensory characteristics, thus identifying the most promising ones for the market. Fruits from improved genotypes of the Solo group (CMF H10.60, CMF L78, and UC 14) and Formosa group (CMF L10, UC 10, and UC 12) were evaluated, and the commercial cultivars Golden and Tainung nº 1 were used as controls. The following physical and physicochemical evaluations were performed: fruit length and diameter, fruit inner cavity diameter, fruit weight, fruit and pulp firmness, soluble solids, pH, titratable acidity, Ratio (soluble solids and titratable acidit relation), and firmness of peeled and unpeeled ripe fruits. Sensory tests were performed with 50 papaya consumers. In general, the improved genotypes of the Solo and Formosa groups showed similar physical and physicochemical characteristics to the Golden and Tainung n° 1 controls. The CMF L78 line of the Solo group and the UC10 hybrid of the Formosa group showed similar fruit firmness and ratio characteristics compared to both commercial cultivars. The three new genotypes in the Solo group showed superior sensory characteristics to the commercial cultivar Golden. The internal preference mapping of this group revealed a higher preference for the genotypes UC 14 and CMF L78, for having fruits with more intense color, stronger flavor, and firmer texture than the others. In the Formosa group, the UC 10 genotype outperformed the cultivar Tainung nº 1, with a global acceptance percentage of 96.15%, due to a more intense aroma, color, and flavor. The CMF L78 line of the Solo group and the UC 10 hybrid of the Formosa group have excellent physicochemical and sensory characteristics and are therefore promising alternatives to replace both commercial cultivars (Golden and Tainung nº 1).

Effect of Zn2+ and its addition sequence on flotation separation of scheelite from calcite using water glass

Flotation separation of scheelite from calcite remains a challenge because of the presence of Ca active sites on both mineral surfaces and of their similar physicochemical characteristics. In this study, the effect of Zn2+ and its addition sequence on flotation separation of scheelite from calcite was investigated via micro-flotation experiments, zeta potential measurements, solution chemistry calculations, and X-ray photoelectron spectroscopy (XPS) tests. The Zn-water glass (a mixture of Zn2+ and water glass) exhibits a better selective depression effect on calcite than the water glass alone but is much less sensitive to scheelite flotation. However, when Zn2+ is added prior to the water glass, both scheelite and calcite are significantly depressed. The superior selective depression effect of Zn-water glass arises from the selective adsorption of the Zn-silicate polymer and Si(OH)4 on the calcite surface, while the significant non-selective depression effect of Zn2+ added prior to the water glass is due to the adsorption of the hydrophilic Zn species on both scheelite and calcite surfaces.

Bran of cassava starch flour and bran of cassava flour as potential tablet excipients

Objectives: The physicochemical characteristics of bran of cassava starch flour and bran of cassava flour (viz. organoleptic characteristics, pH value, moisture content, total ashes, lipid, protein, starch and fiber contents) and biopharmacotechnical parameters (viz. granulometry, flow capacity, angle at rest, outflow time and apparent density) were evaluated aiming at assessing their potential use as tablet excipients. Methodos: Three tablet formulations of venlafaxine hydrochloride were proposed, having as excipients bran of cassava flour, bran of cassava starch flour and Starch 1500®. The tablets were produced using two different pressures (98±5 MPa and 32±6 Mpa) and their mechanical (hardness and friability) and dissolubility characteristics were evaluated. Results and Conclusions: The tablets produced with both cassava flours, using higher pressures, presented similar physicochemical characteristics to those obtained with the excipient Starch1500®, thus indicating that cassava flours possess the potential to be used as disintegrating agents in tablets.

Characteristic of carrageenan Eucheuma cottonii collected from the coast of Tanjung Medang Village and Jaga Island, Riau

Carrageenan is a group of polysaccharides extracted from red seaweed. Carrageenan extraction can be done by several methods, one of which is alkaline solution (KOH) because KOH produces a stronger gel than other alkalis. Carrageenan was extracted using hot alkali followed by precipitation, drying, and milling. The purpose of this study was to determine the chemical composition of dried E. cottonii from North Tanjung Medang Village and Jaga island coastal sea regions and physico-chemical characteristics of carrageenan extracted with KOH solutions 4, 8 and 12%. The results of analysis showed that the chemical composition of dried E.cottonii of both costal sea regions not significant. The chemical characteristics of carrageenan from Tanjung Medang Village and Jaga Island using KOH 4, 8, and 12%, were moisture (11-8%), ash (27-36%), acid-insoluble ash (1.66-2.0%), and sulphate content (24-29%), those not significant all carrageenan except ash content. Whereas the physical characteristics of both carrageenan were significantly different. The results of this study indicated that the carrageenan extracted with KOH (4.8, and 12%) has similar physico-chemical characteristics except for gel strength, viscosity, and ash content.

Physico-chemical characterization and antioxidant capacity of the colombian berry (Vaccinium meridionale Swartz) with a high-polyphenol content: potential effects in people with metabolic syndrome

Abstract Colombian berry (agraz) has demonstrated a high antioxidant content in vitro. In the present study, it was elaborated and characterized an agraz nectar, designed a placebo with similar physicochemical and sensorial characteristics of the agraz nectar, but without polyphenols; and evaluated their antioxidant capacity both in vitro and in vivo in adults with cardiovascular risk factors. The polyphenolic concentration of the agraz nectar and its antioxidant capacity was superior than other reported for this fruit. A high content of total cyanidins was observed in the freeze-dried agraz, but not delphinin was detected by HPLC. For the intervention study, sixty-six subjects, with at least three cardiometabolic risk factors, consumed agraz nectar or placebo daily during 4 weeks each, separated by a 4-week washout period. Total phenol concentration and antioxidant capacity in the participants’ serum were not statistically different after consuming agraz nectar and placebo. However, women increased significantly their serum DPPH scavenging capacity after consuming agraz nectar, compared to placebo. This is one of the first studies showing data about the effects of this colombian berry on the antioxidant capacity in people with metabolic syndrome.

Sustainable synthesis of natural deep eutectic solvents (NADES) by different methods

Natural deep eutectic solvents (NADES) based on malic acid-citric acid-water (MA-CA), xylitol-citric acid-water (Xyl-CA) and xylitol-malic acid-water (Xyl-MA) were prepared according to three different methods: controlled heating and stirring, ultrasound-assisted synthesis (UAS), and microwave-assisted synthesis (MAS), in each case employing a 1:1:10 M ratio. The NADES were characterized by infrared spectroscopy (ATR-FTIR), which indicated the formation of intermolecular interactions such as hydrogen bonds between the precursors, irrespective of the synthesis method. Thermogravimetric analysis (TGA) was used to obtain the thermal decomposition profiles of the synthesized solvents, which evidenced interactions between the precursors and decomposition temperatures higher than 150 °C. Determination of the physical properties showed no significant differences of viscosity and density among the NADES produced using the different synthesis methods, at a 95% confidence level. Hence, all the methods used for the synthesis of NADES resulted in solvents with similar physicochemical characteristics. The syntheses assisted by ultrasound and microwaves were faster and efficient, while advantages of the stirring and heating method included the use of simpler equipment and the ability to produce larger volumes of solvents.

Investigation of thermal decomposition as a critical factor inhibiting cold crystallization in amorphous sucrose prepared by melt-quenching

Researchers have reported that freeze-dried (FreD), spray-dried (SprayD), and ball milled (BallM) amorphous sucrose exhibit cold crystallization, whereas melt-quenched (MeltQ) does not. Three main explanations have been proposed to account for the lack of MeltQ cold crystallization: absence of crystal nuclei, lower sample moisture content, and dissimilarity to the crystalline state. However, in light of recent research revealing the presence of thermal decomposition indicator compounds in MeltQ sucrose, but not in FreD and SprayD, it is our objective to determine if thermal decomposition is also a plausible explanation for the lack of MeltQ cold crystallization. To achieve this objective, the physicochemical characteristics and thermal behavior of freeze-dried melt-quenched amorphous sucrose (FreD-MeltQ) were compared to those of MeltQ and FreD. Despite similar physicochemical characteristics to FreD, FreD-MeltQ did not exhibit cold crystallization. Powder X-ray diffraction and total scattering pair distribution function analysis showed that MeltQ and FreD-MeltQ had a more similar local structure to one another than to FreD. The underlying cause of these structural differences appears to be the presence of thermal decomposition compounds, with MeltQ and FreD-MeltQ containing similar amounts of thermal decomposition indicator compounds (7–8% glucose, 0.5–1% fructose, 0.2% 5-HMF, and 0.5% 1-kestose) and FreD containing none. Based on this evidence, we assert that thermal decomposition is an additional factor that contributes to the lack of cold crystallization in MeltQ sucrose.

Pegfilgrastim-jmdb/MYL-1401H: A Pegfilgrastim Biosimilar

Pegfilgrastim-jmdb/MYL-1401H (FULPHILA™) [hereafter referred to as pegfilgrastim-jmdb] is a biosimilar of the reference pegylated recombinant granulocyte colony-stimulating factor pegfilgrastim. It is approved for use in patients receiving chemotherapy for malignancy to decrease the incidence of infection, as manifested by febrile neutropenia, in the USA and to reduce the duration of neutropenia and the incidence of febrile neutropenia in the EU. Pegfilgrastim-jmdb has similar physicochemical characteristics and functional properties to those of US- and EU-sourced reference pegfilgrastim, and the pharmacodynamic and pharmacokinetic similarity of the agents has also been demonstrated in healthy volunteers. Pegfilgrastim-jmdb demonstrated clinical efficacy equivalent to that of EU-sourced reference pegfilgrastim in patients with newly diagnosed Stage II/III breast cancer receiving neoadjuvant or adjuvant chemotherapy and was generally well tolerated in this patient population. The overall safety profile and immunogenic potential of the two agents was similar. The role of reference pegfilgrastim in the management of chemotherapy-induced neutropenia is well established and pegfilgrastim-jmdb provides an effective biosimilar alternative for patients requiring pegfilgrastim therapy.

Oven drying and hot water cooking processes decrease HCN contents of cassava leaves

The aim of this work was to study the effects of temperature and time of oven drying and hot water cooking processes on HCN (hydrocyanic acid) degradation of cassava leaves as a contribution for obtaining a safe product for human consumption. Nine varieties of cassava leaves collected in the Amazonian region of Brazil (Pará State) were characterized regarding moisture, pH, total acidity, ashes, total lipids, total protein, water activity, carbohydrates, total energetic value and HCN contents. The leaves of the three cassava varieties, which presented the highest HCN contents, were submitted to the thermal degradation of HCN, under drying and boiling conditions. All the leaves presented similar physicochemical characteristics and the HCN contents varied from 90.6 to 560.9 mg HCN/kg fresh leaves (total HCN) and from 16.6 to 59.2 mg HCN/kg fresh leaves (free HCN). Thermal degradation studies on HCN showed that the drying and boiling processes were effective on total HCN removal after 180 min. Furthermore, a remarkable decrease in HCN contents was observed after 20 min of boiling. Regarding free HCN, the drying method was more effective than boiling, showing high degradation percentages: 74.1%–92.2% to 1.1%–72.4%, respectively.

Spatial-economic optimisation of biomethane injection into natural gas grid: The case at southern Malaysia

Energy is widely used in industry for heating and cooling, with natural gas (NG) being the largest primary energy source in Malaysia, closely followed by coal. Renewable energy, such as biogas upgrading to biomethane, could cut the use of fossil fuels by supplementing NG usage due to their similar physicochemical and thermochemical characteristics. Biogas production plants in Malaysia are more commonly seen in waste-to-energy scenarios, with the technology anaerobic digestion, and their deployment is supported via feed-in tariffs (FiT) for power generation. Other potential applications such as the conversion of biogas into biomethane, injection into the natural gas grid or transportation through a virtual pipeline may still need further technical development. This paper presents spatial techno economic optimisation modelling using BeWhere to determine decentralised biomethane production plants using feedstock from multiple sources of biogas, including palm oil mill effluent (POME), food waste, cattle manure and chicken manure. This model considered potential configurations and sizes of the biomethane plants, the transportation of biomethane using a virtual pipeline (at 250 psig) and demand in one of the states in Malaysia, namely Johor. It was found that two to four biomethane plants with capacities ranging between 125 and 700 m3/h were located in densely populated areas or heavier industrial consumers when the carbon tax was implemented at 167.71 EUR/tCO2 (800 MYR/tCO2). Sensitivity analysis suggested that biomethane production increases with the increasing country renewable energy share target to beyond 2080 MW. It is recommended that specific policy regulations and Feed-in Tariff (FiT) mechanisms are used to expand the biomethane market share in the country.

PF-06438179/GP1111: An Infliximab Biosimilar.

PF-06438179/GP1111 (Zessly®; Ixifi®) [hereafter referred to as GP1111] is a biosimilar of the reference monoclonal anti-TNF-α antibody infliximab, and is approved in the EU and USA for the same indications as the reference drug, including rheumatoid arthritis (RA), Crohn’s disease, ulcerative colitis (including paediatric ulcerative colitis in the EU), ankylosing spondylitis, psoriatic arthritis and plaque psoriasis; GP1111 is also approved in Japan. GP1111 has similar physicochemical characteristics and pharmacodynamic properties to those of reference infliximab, and the pharmacokinetic similarity of the agents has been shown in healthy volunteers and patients with moderate-to-severe RA despite methotrexate therapy. GP1111 demonstrated clinical efficacy equivalent to that of reference infliximab in patients with moderate-to-severe RA, despite methotrexate therapy, and was generally well tolerated in this population. The tolerability, immunogenicity and safety profiles of GP1111 were similar to those of reference infliximab, and switching from reference infliximab to GP1111 had no impact on safety, efficacy or immunogenicity. The role of reference infliximab in the management of autoimmune inflammatory conditions is well established and GP1111 provides an effective biosimilar alternative for patients requiring infliximab therapy.

Oil Extraction from Rana catesbeiana by Supercritical Carbon Dioxide and Mechanical Pressing

AbstractOil extraction from the fat body of bullfrog (FBB) using supercritical carbon dioxide through supercritical fluid extraction (SFE) and mechanical pressing (ME) was assessed. ME extraction was performed within a temperature range from 40 to 90 °C and the SFE at 40 °C and 15 MPa. The peroxide index (PI) and oxidative induction time (OIT) of the oil obtained from the ME were negatively influenced by the increase in the extraction temperature; however, the FBB oil extracted at 40 °C presented a high quality with acidity index and PI values of 4.7 mg KOH g−1 and 0.50 mEq kg−1, respectively. The oils obtained from both processes presented similar physicochemical characteristics, especially related to the composition. Significant amounts of ω‐3 (≈3.5%), ω‐6 (≈19%), and ω‐9 (≈50%) fatty acids were achieved. Thus, the valorization of the FBB through the recovery of its oil may be of great interest mainly due to the high yields achieved (66.7%).

The depression behavior and mechanism of carboxymethyl chitosan on calcite flotation

The separation of scheelite and calcite by froth flotation is difficulty as these two minerals have similar physicochemical characteristics. To solve this problem, the role of carboxymethyl chitosan in the flotation separation of scheelite from calcite has been studied and the depression mechanism has been discussed. Micro-flotation tests show that carboxymethyl chitosan has strong depression effect on calcite and the depression effect decreased with the increase of pH. However, its depression effect on scheelite is weak. A concentrate with WO3 grade of 65.21% and WO3 recovery of 77.48% can be achieved in the mixed minerals flotation when carboxymethyl chitosan was used. The adsorption tests show that carboxymethyl chitosan has adsorbed on the calcite surface and the adsorption amount increased with the increase of added amount. The adsorption mechanism of carboxymethyl chitosan on calcite surface was analyzed through the X-ray photoelectron spectroscopy (XPS) tests and the results revealed that carboxymethyl chitosan adsorbed on calcite surface mainly through chemical interaction.