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  <element id="agx_CostIncurredRelatedToActivitiesToDevelopGasFiredPowerPlant" name="CostIncurredRelatedToActivitiesToDevelopGasFiredPowerPlant" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="agx_OperatingLeaseAndShortTermRentalAgreementsExpense" name="OperatingLeaseAndShortTermRentalAgreementsExpense" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="agx_CountryOtherMember" name="CountryOtherMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="agx_EffectiveIncomeTaxRateReconciliationBadDebtLoss" name="EffectiveIncomeTaxRateReconciliationBadDebtLoss" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="agx_GainLossOnGrantOfUtilitiesEasement" name="GainLossOnGrantOfUtilitiesEasement" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="agx_IncomeTaxBenefitFederalAndState" name="IncomeTaxBenefitFederalAndState" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="agx_PaymentOfInterestAndArbitrationFees" name="PaymentOfInterestAndArbitrationFees" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="agx_IncreaseInLossCarrybackPeriodForCertainLosses" name="IncreaseInLossCarrybackPeriodForCertainLosses" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="agx_EffectiveIncomeTaxRateReconciliationNetOperatingLossBenefitsEliminationAmount" name="EffectiveIncomeTaxRateReconciliationNetOperatingLossBenefitsEliminationAmount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="agx_EffectiveIncomeTaxRateReconciliationNetOperatingLossCarryforwardAmountUtilization" name="EffectiveIncomeTaxRateReconciliationNetOperatingLossCarryforwardAmountUtilization" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
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  <element id="agx_ReversalOfProfitLossRecordedInPriorPeriods" name="ReversalOfProfitLossRecordedInPriorPeriods" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
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  <element id="agx_AccountsReceivableAndContractWithCustomerAssetNetCurrent" name="AccountsReceivableAndContractWithCustomerAssetNetCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="agx_NPricedChangeOrdersIncludedInTransactionPrices" name="NPricedChangeOrdersIncludedInTransactionPrices" nillable="true" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
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  <element id="agx_AmountOutstandingLetterOfCreditIssuedByBankInSupportOfProjectDevelopmentActivitiesAndDepositedInBankAsCollateral" name="AmountOutstandingLetterOfCreditIssuedByBankInSupportOfProjectDevelopmentActivitiesAndDepositedInBankAsCollateral" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="agx_PercentageOfMaximumSharesForTargetNumberOfSharesAwarded" name="PercentageOfMaximumSharesForTargetNumberOfSharesAwarded" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
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  <element id="agx_GemmaPowerSystemLlcMember" name="GemmaPowerSystemLlcMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
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  <element id="agx_IcfrAuditorAttestationFlag" name="IcfrAuditorAttestationFlag" nillable="true" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="agx_PercentageOfExpectedAnnualGrowthRateAfterYearThree" name="PercentageOfExpectedAnnualGrowthRateAfterYearThree" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="agx_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExcessExecutiveCompensationAmount" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExcessExecutiveCompensationAmount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
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  <element id="agx_DeferredTaxLiabilitiesRightOfUseAssets" name="DeferredTaxLiabilitiesRightOfUseAssets" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="agx_EstimatedValueOfFutureWorkCoveredByOutstandingPerformanceBonds" name="EstimatedValueOfFutureWorkCoveredByOutstandingPerformanceBonds" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="agx_BondsOutstandingCoveringOtherRisks" name="BondsOutstandingCoveringOtherRisks" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
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  <element id="agx_ExcessOfFairValueAtTrestDateOverCarryingValue" name="ExcessOfFairValueAtTrestDateOverCarryingValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
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</schema>
